72 files changed, 3335 insertions, 2088 deletions
diff --git a/.cargo/config b/.cargo/config
index c319d33f2..b9db30c96 100644
--- a/.cargo/config
+++ b/.cargo/config
@@ -1,10 +1,16 @@
 [alias]
 # Automatically generates the ast and syntax kinds files
-gen-syntax =   "run --package tools --bin tools -- gen-syntax"
+gen-syntax   = "run --package tools --bin tools -- gen-syntax"
-gen-tests =    "run --package tools --bin tools -- gen-tests"
+# Extracts the tests from 
+gen-tests    = "run --package tools --bin tools -- gen-tests"
+# Installs the visual studio code extension
 install-code = "run --package tools --bin tools -- install-code"
-format =       "run --package tools --bin tools -- format"
+# Formats the full repository or installs the git hook to do it automatically.
-format-hook =  "run --package tools --bin tools -- format-hook"
+format       = "run --package tools --bin tools -- format"
+format-hook  = "run --package tools --bin tools -- format-hook"
+# Runs the fuzzing test suite (currently only parser)
+fuzz-tests   = "run --package tools --bin tools -- fuzz-tests"
-render-test =  "run --package ra_cli -- render-test"
+render-test  = "run --package ra_cli -- render-test"
-parse =        "run --package ra_cli -- parse"
+# Parse a file. This should be piped the file contents
+parse        = "run --package ra_cli -- parse"
diff --git a/.travis.yml b/.travis.yml
index 04bb3be37..86bce93d6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,6 +10,7 @@ build: &rust_build
    script:
        - cargo gen-tests --verify
        - cargo gen-syntax --verify
+        - cargo test --no-run  # let's measure compile time separately
        - cargo test
    env:
        - RUSTFLAGS="-D warnings", CARGO_INCREMENTAL=0
@@ -25,7 +26,7 @@ matrix:
              - cd editors/code && npm ci && npm run travis
        - os: windows
-          if: branch = master
+          if: branch = master AND type = push
          before_script:
              - dos2unix ./crates/ra_syntax/tests/data/parser/**/*.txt
              - dos2unix ./crates/ra_syntax/tests/data/parser/**/*.rs
diff --git a/Cargo.lock b/Cargo.lock
index f06da0050..5f35f2872 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -48,7 +48,7 @@ version = "0.3.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "autocfg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "backtrace-sys 0.1.26 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace-sys 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
 "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-demangle 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -57,10 +57,10 @@ dependencies = [
 [[package]]
 name = "backtrace-sys"
-version = "0.1.26"
+version = "0.1.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -117,14 +117,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "error-chain 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_derive 1.0.82 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "cc"
-version = "1.0.27"
+version = "1.0.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -340,8 +340,8 @@ dependencies = [
 "failure 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "languageserver-types 0.53.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -425,9 +425,9 @@ dependencies = [
 "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-derive 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_derive 1.0.82 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 "url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "url_serde 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -587,7 +587,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "pest"
-version = "2.0.2"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "ucd-trie 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -595,32 +595,32 @@ dependencies = [
 [[package]]
 name = "pest_derive"
-version = "2.0.1"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "pest 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pest_generator 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest_generator 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "pest_generator"
-version = "2.0.0"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "pest 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pest_meta 2.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest_meta 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "proc-macro2 0.4.24 (registry+https://github.com/rust-lang/crates.io-index)",
 "quote 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.14.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.23 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "pest_meta"
-version = "2.0.3"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "maplit 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "pest 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "sha-1 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -667,6 +667,7 @@ name = "ra_analysis"
 version = "0.1.0"
 dependencies = [
 "fst 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "parking_lot 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "ra_db 0.1.0",
@@ -679,6 +680,7 @@ dependencies = [
 "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "salsa 0.9.0 (git+https://github.com/matklad/salsa.git?branch=transitive-untracked)",
 "test_utils 0.1.0",
+ "unicase 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -762,8 +764,8 @@ dependencies = [
 "rayon 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "relative-path 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 "smol_str 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
 "tempfile 3.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 "test_utils 0.1.0",
@@ -921,7 +923,7 @@ dependencies = [
 [[package]]
 name = "redox_syscall"
-version = "0.1.44"
+version = "0.1.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -929,7 +931,7 @@ name = "redox_termios"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.50 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -972,7 +974,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "base64 0.9.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -1060,7 +1062,7 @@ version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -1070,15 +1072,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "serde"
-version = "1.0.83"
+version = "1.0.84"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde_derive 1.0.82 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "serde_derive"
-version = "1.0.82"
+version = "1.0.84"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "proc-macro2 0.4.24 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1088,12 +1090,12 @@ dependencies = [
 [[package]]
 name = "serde_json"
-version = "1.0.33"
+version = "1.0.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "itoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "ryu 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -1128,7 +1130,7 @@ name = "smol_str"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -1148,16 +1150,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "syn"
-version = "0.14.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "proc-macro2 0.4.24 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-[[package]]
-name = "syn"
 version = "0.15.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
@@ -1185,7 +1177,7 @@ dependencies = [
 "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.50 (registry+https://github.com/rust-lang/crates.io-index)",
 "remove_dir_all 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1200,11 +1192,11 @@ dependencies = [
 "glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 "humansize 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pest 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pest_derive 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pest_derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "regex 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 "slug 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "unic-segment 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1227,7 +1219,7 @@ version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.50 (registry+https://github.com/rust-lang/crates.io-index)",
 "redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1237,7 +1229,7 @@ version = "0.1.0"
 dependencies = [
 "difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)",
 "text_unit 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1246,7 +1238,7 @@ name = "text_unit"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -1288,7 +1280,7 @@ version = "0.1.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.50 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1363,6 +1355,14 @@ dependencies = [
 ]
 [[package]]
+name = "unicase"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+[[package]]
 name = "unicode-bidi"
 version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1413,7 +1413,7 @@ name = "url_serde"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)",
 "url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1490,7 +1490,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
 "checksum autocfg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4e5f34df7a019573fb8bdc7e24a2bfebe51a2a1d6bfdbaeccedb3c41fc574727"
 "checksum backtrace 0.3.13 (registry+https://github.com/rust-lang/crates.io-index)" = "b5b493b66e03090ebc4343eb02f94ff944e0cbc9ac6571491d170ba026741eb5"
-"checksum backtrace-sys 0.1.26 (registry+https://github.com/rust-lang/crates.io-index)" = "3fcce89e5ad5c8949caa9434501f7b55415b3e7ad5270cb88c75a8d35e8f1279"
+"checksum backtrace-sys 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)" = "797c830ac25ccc92a7f8a7b9862bde440715531514594a6154e3d4a54dd769b6"
 "checksum base64 0.9.3 (registry+https://github.com/rust-lang/crates.io-index)" = "489d6c0ed21b11d038c31b6ceccca973e65d73ba3bd8ecb9a2babf5546164643"
 "checksum bit-set 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6f1efcc46c18245a69c38fcc5cc650f16d3a59d034f3106e9ed63748f695730a"
 "checksum bit-vec 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4440d5cb623bb7390ae27fec0bb6c61111969860f8e3ae198bfa0663645e67cf"
@@ -1499,7 +1499,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum byte-tools 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "560c32574a12a89ecd91f5e742165893f86e3ab98d21f8ea548658eb9eef5f40"
 "checksum byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "94f88df23a25417badc922ab0f5716cc1330e87f71ddd9203b3a3ccd9cedf75d"
 "checksum cargo_metadata 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "e5d1b4d380e1bab994591a24c2bdd1b054f64b60bef483a8c598c7c345bc3bbe"
-"checksum cc 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)" = "155ed195f7bd722d1dfeb30365b9d0c1f6a078fa7ca4014497e5935d90993d6f"
+"checksum cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)" = "bb4a8b715cb4597106ea87c7c84b2f1d452c7492033765df7f32651e66fcf749"
 "checksum cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "082bb9b28e00d3c9d39cc03e64ce4cea0f1bb9b3fde493f0cbc008472d22bdf4"
 "checksum chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "45912881121cb26fad7c38c17ba7daa18764771836b34fab7d3fbd93ed633878"
 "checksum clap 2.32.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b957d88f4b6a63b9d70d5f454ac8011819c6efa7727858f458ab71c756ce2d3e"
@@ -1557,10 +1557,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum parking_lot_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ad7f7e6ebdc79edff6fdcb87a55b620174f7a989e3eb31b65231f4af57f00b8c"
 "checksum parking_lot_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "94c8c7923936b28d546dfd14d4472eaf34c99b14e1c973a32b3e6d4eb04298c9"
 "checksum percent-encoding 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "31010dd2e1ac33d5b46a5b413495239882813e0369f8ed8a5e266f173602f831"
-"checksum pest 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a677051ad923732bb5c70f2d45f8985a96e3eee2e2bff86697e3b11b0c3fcfde"
+"checksum pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "54f0c72a98d8ab3c99560bfd16df8059cc10e1f9a8e83e6e3b97718dd766e9c3"
-"checksum pest_derive 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b76f477146419bc539a63f4ef40e902166cb43b3e51cecc71d9136fd12c567e7"
+"checksum pest_derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "833d1ae558dc601e9a60366421196a8d94bc0ac980476d0b67e1d0988d72b2d0"
-"checksum pest_generator 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3ebee4e9680be4fd162e6f3394ae4192a6b60b1e4d17d845e631f0c68d1a3386"
+"checksum pest_generator 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "63120576c4efd69615b5537d3d052257328a4ca82876771d6944424ccfd9f646"
-"checksum pest_meta 2.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1f6d5f6f0e6082578c86af197d780dc38328e3f768cec06aac9bc46d714e8221"
+"checksum pest_meta 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f5a3492a4ed208ffc247adcdcc7ba2a95be3104f58877d0d02f0df39bf3efb5e"
 "checksum proc-macro2 0.4.24 (registry+https://github.com/rust-lang/crates.io-index)" = "77619697826f31a02ae974457af0b29b723e5619e113e9397b8b82c6bd253f09"
 "checksum proptest 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)" = "926d0604475349f463fe44130aae73f2294b5309ab2ca0310b998bd334ef191f"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
@@ -1576,7 +1576,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "effa3fcaa47e18db002bdde6060944b6d2f9cfd8db471c30e873448ad9187be3"
 "checksum rayon 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "373814f27745b2686b350dd261bfd24576a6fb0e2c5919b3a2b6005f820b0473"
 "checksum rayon-core 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b055d1e92aba6877574d8fe604a63c8b5df60f60e5982bf7ccbb1338ea527356"
-"checksum redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)" = "a84bcd297b87a545980a2d25a0beb72a1f490c31f0a9fde52fca35bfbb1ceb70"
+"checksum redox_syscall 0.1.50 (registry+https://github.com/rust-lang/crates.io-index)" = "52ee9a534dc1301776eff45b4fa92d2c39b1d8c3d3357e6eb593e0d795506fc2"
 "checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
 "checksum regex 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "37e7cbbd370869ce2e8dff25c7018702d10b21a20ef7135316f8daecd6c25b7f"
 "checksum regex-syntax 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "4e47a2ed29da7a9e1960e1639e7a982e6edc6d49be308a3b02daf511504a16d1"
@@ -1595,9 +1595,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "94258f53601af11e6a49f722422f6e3425c52b06245a5cf9bc09908b174f5e27"
 "checksum semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
 "checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
-"checksum serde 1.0.83 (registry+https://github.com/rust-lang/crates.io-index)" = "157e12af46859e968da75dea9845530e13d03bcab2009a41b9b7bb3cf4eb3ec2"
+"checksum serde 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)" = "0e732ed5a5592c17d961555e3b552985baf98d50ce418b7b655f31f6ba7eb1b7"
-"checksum serde_derive 1.0.82 (registry+https://github.com/rust-lang/crates.io-index)" = "96a7f9496ac65a2db5929afa087b54f8fc5008dcfbe48a8874ed20049b0d6154"
+"checksum serde_derive 1.0.84 (registry+https://github.com/rust-lang/crates.io-index)" = "b4d6115a3ca25c224e409185325afc16a0d5aaaabc15c42b09587d6f1ba39a5b"
-"checksum serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)" = "c37ccd6be3ed1fdf419ee848f7c758eb31b054d7cd3ae3600e3bae0adf569811"
+"checksum serde_json 1.0.34 (registry+https://github.com/rust-lang/crates.io-index)" = "bdf540260cfee6da923831f4776ddc495ada940c30117977c70f1313a6130545"
 "checksum sha-1 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "51b9d1f3b5de8a167ab06834a7c883bd197f2191e1dda1a22d9ccfeedbf9aded"
 "checksum slug 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "b3bc762e6a4b6c6fcaade73e77f9ebc6991b676f88bb2358bddb56560f073373"
 "checksum smallvec 0.6.7 (registry+https://github.com/rust-lang/crates.io-index)" = "b73ea3738b47563803ef814925e69be00799a8c07420be8b996f8e98fb2336db"
@@ -1605,7 +1605,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
 "checksum strsim 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bb4f380125926a99e52bc279241539c018323fab05ad6368b56f93d9369ff550"
 "checksum superslice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b50b13d42370e0f5fc62eafdd5c2d20065eaf5458dab215ff3e20e63eea96b30"
-"checksum syn 0.14.9 (registry+https://github.com/rust-lang/crates.io-index)" = "261ae9ecaa397c42b960649561949d69311f08eeaea86a65696e6e46517cf741"
 "checksum syn 0.15.23 (registry+https://github.com/rust-lang/crates.io-index)" = "9545a6a093a3f0bd59adb472700acc08cad3776f860f16a897dfce8c88721cbc"
 "checksum synstructure 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)" = "73687139bf99285483c96ac0add482c3776528beac1d97d444f6e91f203a2015"
 "checksum tempfile 3.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "7e91405c14320e5c79b3d148e1c86f40749a36e490642202a31689cb1a3452b2"
@@ -1626,6 +1625,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum unic-segment 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c9ca47cbb09fb5fcd066b5867d11dc528302fa465277882797d6a836e1ee6f9e"
 "checksum unic-ucd-segment 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "48f1a08ce0409a9e391b88d1930118eec48af12742fc538bcec55f775865776e"
 "checksum unic-ucd-version 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1f5e6c6c53c2d0ece4a5964bc55fcff8602153063cb4fab20958ff32998ff6"
+"checksum unicase 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9d3218ea14b4edcaccfa0df0a64a3792a2c32cc706f1b336e48867f9d3147f90"
 "checksum unicode-bidi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "49f2bd0c6468a8230e1db229cff8029217cf623c767ea5d60bfbd42729ea54d5"
 "checksum unicode-normalization 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "6a0180bc61fc5a987082bfa111f4cc95c4caff7f9799f3e46df09163a937aa25"
 "checksum unicode-segmentation 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "aa6024fc12ddfd1c6dbc14a80fa2324d4568849869b779f6bd37e5e4c03344d1"
diff --git a/crates/gen_lsp_server/Cargo.toml b/crates/gen_lsp_server/Cargo.toml
index ff475f196..a421a3e0b 100644
--- a/crates/gen_lsp_server/Cargo.toml
+++ b/crates/gen_lsp_server/Cargo.toml
@@ -11,6 +11,6 @@ description = "Generic LSP server scaffold."
 languageserver-types = "0.53.1"
 log = "0.4.3"
 failure = "0.1.4"
-serde_json = "1.0.24"
+serde_json = "1.0.34"
 serde = { version = "1.0.83", features = ["derive"] }
 crossbeam-channel = "0.3.5"
diff --git a/crates/ra_analysis/Cargo.toml b/crates/ra_analysis/Cargo.toml
index a5d4f65ab..7a4fdaed9 100644
--- a/crates/ra_analysis/Cargo.toml
+++ b/crates/ra_analysis/Cargo.toml
@@ -5,6 +5,7 @@ version = "0.1.0"
 authors = ["Aleksey Kladov <[email protected]>"]
 [dependencies]
+itertools = "0.8.0"
 log = "0.4.5"
 relative-path = "0.4.0"
 rayon = "1.0.2"
@@ -12,6 +13,8 @@ fst = "0.3.1"
 salsa = "0.9.0"
 rustc-hash = "1.0"
 parking_lot = "0.7.0"
+unicase = "2.2.0"
 ra_syntax = { path = "../ra_syntax" }
 ra_editor = { path = "../ra_editor" }
 ra_text_edit = { path = "../ra_text_edit" }
diff --git a/crates/ra_analysis/src/completion.rs b/crates/ra_analysis/src/completion.rs
index fe580700f..ce777a771 100644
--- a/crates/ra_analysis/src/completion.rs
+++ b/crates/ra_analysis/src/completion.rs
@@ -28,7 +28,21 @@ pub use crate::completion::completion_item::{CompletionItem, InsertText, Complet
 /// incomplete and can look really weird.
 ///
 /// Once the context is collected, we run a series of completion routines which
-/// look at the context and produce completion items.
+/// look at the context and produce completion items. One subtelty about this
+/// phase is that completion engine should not filter by the substring which is
+/// already present, it should give all possible variants for the identifier at
+/// the caret. In other words, for
+///
+/// ```no-run
+/// fn f() {
+///     let foo = 92;
+///     let _ = bar<|>
+/// }
+/// ```
+///
+/// `foo` *should* be present among the completion variants. Filtering by
+/// identifier prefix/fuzzy match should be done higher in the stack, together
+/// with ordering of completions (currently this is done by the client).
 pub(crate) fn completions(
    db: &db::RootDatabase,
    position: FilePosition,
@@ -40,6 +54,7 @@ pub(crate) fn completions(
    complete_fn_param::complete_fn_param(&mut acc, &ctx);
    complete_keyword::complete_expr_keyword(&mut acc, &ctx);
+    complete_keyword::complete_use_tree_keyword(&mut acc, &ctx);
    complete_snippet::complete_expr_snippet(&mut acc, &ctx);
    complete_snippet::complete_item_snippet(&mut acc, &ctx);
    complete_path::complete_path(&mut acc, &ctx)?;
@@ -57,6 +72,6 @@ fn check_completion(code: &str, expected_completions: &str, kind: CompletionKind
    } else {
        single_file_with_position(code)
    };
-    let completions = completions(&analysis.imp.db, position).unwrap().unwrap();
+    let completions = completions(&analysis.db, position).unwrap().unwrap();
    completions.assert_match(expected_completions, kind);
 }
diff --git a/crates/ra_analysis/src/completion/complete_keyword.rs b/crates/ra_analysis/src/completion/complete_keyword.rs
index d70fdaada..28194c908 100644
--- a/crates/ra_analysis/src/completion/complete_keyword.rs
+++ b/crates/ra_analysis/src/completion/complete_keyword.rs
@@ -7,6 +7,38 @@ use ra_syntax::{
 use crate::completion::{CompletionContext, CompletionItem, Completions, CompletionKind, CompletionItemKind};
+pub(super) fn complete_use_tree_keyword(acc: &mut Completions, ctx: &CompletionContext) {
+    // complete keyword "crate" in use stmt
+    match (ctx.use_item_syntax.as_ref(), ctx.path_prefix.as_ref()) {
+        (Some(_), None) => {
+            CompletionItem::new(CompletionKind::Keyword, "crate")
+                .kind(CompletionItemKind::Keyword)
+                .lookup_by("crate")
+                .snippet("crate::")
+                .add_to(acc);
+            CompletionItem::new(CompletionKind::Keyword, "self")
+                .kind(CompletionItemKind::Keyword)
+                .lookup_by("self")
+                .add_to(acc);
+            CompletionItem::new(CompletionKind::Keyword, "super")
+                .kind(CompletionItemKind::Keyword)
+                .lookup_by("super")
+                .add_to(acc);
+        }
+        (Some(_), Some(_)) => {
+            CompletionItem::new(CompletionKind::Keyword, "self")
+                .kind(CompletionItemKind::Keyword)
+                .lookup_by("self")
+                .add_to(acc);
+            CompletionItem::new(CompletionKind::Keyword, "super")
+                .kind(CompletionItemKind::Keyword)
+                .lookup_by("super")
+                .add_to(acc);
+        }
+        _ => {}
+    }
+}
 fn keyword(kw: &str, snippet: &str) -> CompletionItem {
    CompletionItem::new(CompletionKind::Keyword, kw)
        .kind(CompletionItemKind::Keyword)
@@ -18,6 +50,7 @@ pub(super) fn complete_expr_keyword(acc: &mut Completions, ctx: &CompletionConte
    if !ctx.is_trivial_path {
        return;
    }
    let fn_def = match ctx.function_syntax {
        Some(it) => it,
        None => return,
@@ -80,6 +113,40 @@ mod tests {
    }
    #[test]
+    fn completes_keywords_in_use_stmt() {
+        check_keyword_completion(
+            r"
+            use <|>
+            ",
+            r#"
+            crate "crate" "crate::"
+            self "self"
+            super "super"
+            "#,
+        );
+        check_keyword_completion(
+            r"
+            use a::<|>
+            ",
+            r#"
+            self "self"
+            super "super"
+            "#,
+        );
+        check_keyword_completion(
+            r"
+            use a::{b, <|>}
+            ",
+            r#"
+            self "self"
+            super "super"
+            "#,
+        );
+    }
+    #[test]
    fn completes_various_keywords_in_function() {
        check_keyword_completion(
            r"
diff --git a/crates/ra_analysis/src/completion/complete_scope.rs b/crates/ra_analysis/src/completion/complete_scope.rs
index daf666505..4dead3689 100644
--- a/crates/ra_analysis/src/completion/complete_scope.rs
+++ b/crates/ra_analysis/src/completion/complete_scope.rs
@@ -27,7 +27,7 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) ->
            match res.import {
                None => true,
                Some(import) => {
-                    let range = import.range(ctx.db, module.source().file_id());
+                    let range = import.range(ctx.db, module.file_id());
                    !range.is_subrange(&ctx.leaf.range())
                }
            }
diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_analysis/src/db.rs
index b072a5eba..d7740f0c4 100644
--- a/crates/ra_analysis/src/db.rs
+++ b/crates/ra_analysis/src/db.rs
@@ -1,7 +1,6 @@
 use std::{fmt, sync::Arc};
 use salsa::{self, Database};
 use ra_db::{LocationIntener, BaseDatabase};
-use hir::{self, DefId, DefLoc};
 use crate::{
    symbol_index,
@@ -15,7 +14,8 @@ pub(crate) struct RootDatabase {
 #[derive(Default)]
 struct IdMaps {
-    defs: LocationIntener<DefLoc, DefId>,
+    defs: LocationIntener<hir::DefLoc, hir::DefId>,
+    macros: LocationIntener<hir::MacroCallLoc, hir::MacroCallId>,
 }
 impl fmt::Debug for IdMaps {
@@ -59,12 +59,18 @@ impl salsa::ParallelDatabase for RootDatabase {
 impl BaseDatabase for RootDatabase {}
-impl AsRef<LocationIntener<DefLoc, DefId>> for RootDatabase {
+impl AsRef<LocationIntener<hir::DefLoc, hir::DefId>> for RootDatabase {
-    fn as_ref(&self) -> &LocationIntener<DefLoc, DefId> {
+    fn as_ref(&self) -> &LocationIntener<hir::DefLoc, hir::DefId> {
        &self.id_maps.defs
    }
 }
+impl AsRef<LocationIntener<hir::MacroCallLoc, hir::MacroCallId>> for RootDatabase {
+    fn as_ref(&self) -> &LocationIntener<hir::MacroCallLoc, hir::MacroCallId> {
+        &self.id_maps.macros
+    }
+}
 salsa::database_storage! {
    pub(crate) struct RootDatabaseStorage for RootDatabase {
        impl ra_db::FilesDatabase {
@@ -85,6 +91,8 @@ salsa::database_storage! {
            fn library_symbols() for symbol_index::LibrarySymbolsQuery;
        }
        impl hir::db::HirDatabase {
+            fn hir_source_file() for hir::db::HirSourceFileQuery;
+            fn expand_macro_invocation() for hir::db::ExpandMacroCallQuery;
            fn module_tree() for hir::db::ModuleTreeQuery;
            fn fn_scopes() for hir::db::FnScopesQuery;
            fn file_items() for hir::db::SourceFileItemsQuery;
diff --git a/crates/ra_analysis/src/extend_selection.rs b/crates/ra_analysis/src/extend_selection.rs
index cde6ee101..f1b77f981 100644
--- a/crates/ra_analysis/src/extend_selection.rs
+++ b/crates/ra_analysis/src/extend_selection.rs
@@ -1,6 +1,6 @@
 use ra_db::SyntaxDatabase;
 use ra_syntax::{
-    SyntaxNodeRef, AstNode,
+    SyntaxNodeRef, AstNode, SourceFileNode,
    ast, algo::find_covering_node,
 };
@@ -11,18 +11,23 @@ use crate::{
 pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRange {
    let source_file = db.source_file(frange.file_id);
-    if let Some(macro_call) = find_macro_call(source_file.syntax(), frange.range) {
+    if let Some(range) = extend_selection_in_macro(db, &source_file, frange) {
-        if let Some(exp) = crate::macros::expand(db, frange.file_id, macro_call) {
+        return range;
-            if let Some(dst_range) = exp.map_range_forward(frange.range) {
-                if let Some(dst_range) = ra_editor::extend_selection(exp.source_file(), dst_range) {
-                    if let Some(src_range) = exp.map_range_back(dst_range) {
-                        return src_range;
-                    }
-                }
-            }
-        }
    }
-    ra_editor::extend_selection(&source_file, frange.range).unwrap_or(frange.range)
+    ra_editor::extend_selection(source_file.syntax(), frange.range).unwrap_or(frange.range)
+}
+fn extend_selection_in_macro(
+    _db: &RootDatabase,
+    source_file: &SourceFileNode,
+    frange: FileRange,
+) -> Option<TextRange> {
+    let macro_call = find_macro_call(source_file.syntax(), frange.range)?;
+    let (off, exp) = hir::MacroDef::ast_expand(macro_call)?;
+    let dst_range = exp.map_range_forward(frange.range - off)?;
+    let dst_range = ra_editor::extend_selection(exp.syntax().borrowed(), dst_range)?;
+    let src_range = exp.map_range_back(dst_range)? + off;
+    Some(src_range)
 }
 fn find_macro_call(node: SyntaxNodeRef, range: TextRange) -> Option<ast::MacroCall> {
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index 5ed374c79..eae73c2c4 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -1,59 +1,42 @@
-use std::{
+use std::sync::Arc;
-    fmt,
-    sync::Arc,
-};
-use rayon::prelude::*;
+use salsa::Database;
-use salsa::{Database, ParallelDatabase};
 use hir::{
    self, FnSignatureInfo, Problem, source_binder,
 };
 use ra_db::{FilesDatabase, SourceRoot, SourceRootId, SyntaxDatabase};
-use ra_editor::{self, FileSymbol, find_node_at_offset, LineIndex, LocalEdit, Severity};
+use ra_editor::{self, find_node_at_offset, assists, LocalEdit, Severity};
 use ra_syntax::{
-    algo::find_covering_node,
+    algo::{find_covering_node, visit::{visitor, Visitor}},
    ast::{self, ArgListOwner, Expr, FnDef, NameOwner},
    AstNode, SourceFileNode,
    SyntaxKind::*,
-    SyntaxNodeRef, TextRange, TextUnit,
+    SyntaxNode, SyntaxNodeRef, TextRange, TextUnit,
 };
 use crate::{
    AnalysisChange,
-    Cancelable,
+    Cancelable, NavigationTarget,
-    completion::{CompletionItem, completions},
    CrateId, db, Diagnostic, FileId, FilePosition, FileRange, FileSystemEdit,
    Query, ReferenceResolution, RootChange, SourceChange, SourceFileEdit,
-    symbol_index::{LibrarySymbolsQuery, SymbolIndex, SymbolsDatabase},
+    symbol_index::{LibrarySymbolsQuery, FileSymbol},
 };
-#[derive(Debug, Default)]
+impl db::RootDatabase {
-pub(crate) struct AnalysisHostImpl {
+    pub(crate) fn apply_change(&mut self, change: AnalysisChange) {
-    db: db::RootDatabase,
-}
-impl AnalysisHostImpl {
-    pub fn analysis(&self) -> AnalysisImpl {
-        AnalysisImpl {
-            db: self.db.snapshot(),
-        }
-    }
-    pub fn apply_change(&mut self, change: AnalysisChange) {
        log::info!("apply_change {:?}", change);
        // self.gc_syntax_trees();
        if !change.new_roots.is_empty() {
-            let mut local_roots = Vec::clone(&self.db.local_roots());
+            let mut local_roots = Vec::clone(&self.local_roots());
            for (root_id, is_local) in change.new_roots {
-                self.db
+                self.query_mut(ra_db::SourceRootQuery)
-                    .query_mut(ra_db::SourceRootQuery)
                    .set(root_id, Default::default());
                if is_local {
                    local_roots.push(root_id);
                }
            }
-            self.db
+            self.query_mut(ra_db::LocalRootsQuery)
-                .query_mut(ra_db::LocalRootsQuery)
                .set((), Arc::new(local_roots));
        }
@@ -61,53 +44,44 @@ impl AnalysisHostImpl {
            self.apply_root_change(root_id, root_change);
        }
        for (file_id, text) in change.files_changed {
-            self.db.query_mut(ra_db::FileTextQuery).set(file_id, text)
+            self.query_mut(ra_db::FileTextQuery).set(file_id, text)
        }
        if !change.libraries_added.is_empty() {
-            let mut libraries = Vec::clone(&self.db.library_roots());
+            let mut libraries = Vec::clone(&self.library_roots());
            for library in change.libraries_added {
                libraries.push(library.root_id);
-                self.db
+                self.query_mut(ra_db::SourceRootQuery)
-                    .query_mut(ra_db::SourceRootQuery)
                    .set(library.root_id, Default::default());
-                self.db
+                self.query_mut(LibrarySymbolsQuery)
-                    .query_mut(LibrarySymbolsQuery)
                    .set_constant(library.root_id, Arc::new(library.symbol_index));
                self.apply_root_change(library.root_id, library.root_change);
            }
-            self.db
+            self.query_mut(ra_db::LibraryRootsQuery)
-                .query_mut(ra_db::LibraryRootsQuery)
                .set((), Arc::new(libraries));
        }
        if let Some(crate_graph) = change.crate_graph {
-            self.db
+            self.query_mut(ra_db::CrateGraphQuery)
-                .query_mut(ra_db::CrateGraphQuery)
                .set((), Arc::new(crate_graph))
        }
    }
    fn apply_root_change(&mut self, root_id: SourceRootId, root_change: RootChange) {
-        let mut source_root = SourceRoot::clone(&self.db.source_root(root_id));
+        let mut source_root = SourceRoot::clone(&self.source_root(root_id));
        for add_file in root_change.added {
-            self.db
+            self.query_mut(ra_db::FileTextQuery)
-                .query_mut(ra_db::FileTextQuery)
                .set(add_file.file_id, add_file.text);
-            self.db
+            self.query_mut(ra_db::FileRelativePathQuery)
-                .query_mut(ra_db::FileRelativePathQuery)
                .set(add_file.file_id, add_file.path.clone());
-            self.db
+            self.query_mut(ra_db::FileSourceRootQuery)
-                .query_mut(ra_db::FileSourceRootQuery)
                .set(add_file.file_id, root_id);
            source_root.files.insert(add_file.path, add_file.file_id);
        }
        for remove_file in root_change.removed {
-            self.db
+            self.query_mut(ra_db::FileTextQuery)
-                .query_mut(ra_db::FileTextQuery)
                .set(remove_file.file_id, Default::default());
            source_root.files.remove(&remove_file.path);
        }
-        self.db
+        self.query_mut(ra_db::SourceRootQuery)
-            .query_mut(ra_db::SourceRootQuery)
            .set(root_id, Arc::new(source_root));
    }
@@ -116,142 +90,86 @@ impl AnalysisHostImpl {
    /// syntax trees. However, if we actually do that, everything is recomputed
    /// for some reason. Needs investigation.
    fn gc_syntax_trees(&mut self) {
-        self.db
+        self.query(ra_db::SourceFileQuery)
-            .query(ra_db::SourceFileQuery)
            .sweep(salsa::SweepStrategy::default().discard_values());
-        self.db
+        self.query(hir::db::SourceFileItemsQuery)
-            .query(hir::db::SourceFileItemsQuery)
            .sweep(salsa::SweepStrategy::default().discard_values());
-        self.db
+        self.query(hir::db::FileItemQuery)
-            .query(hir::db::FileItemQuery)
            .sweep(salsa::SweepStrategy::default().discard_values());
    }
 }
-pub(crate) struct AnalysisImpl {
+impl db::RootDatabase {
-    pub(crate) db: salsa::Snapshot<db::RootDatabase>,
-}
-impl fmt::Debug for AnalysisImpl {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        let db: &db::RootDatabase = &self.db;
-        fmt.debug_struct("AnalysisImpl").field("db", db).finish()
-    }
-}
-impl AnalysisImpl {
-    pub fn file_text(&self, file_id: FileId) -> Arc<String> {
-        self.db.file_text(file_id)
-    }
-    pub fn file_syntax(&self, file_id: FileId) -> SourceFileNode {
-        self.db.source_file(file_id)
-    }
-    pub fn file_line_index(&self, file_id: FileId) -> Arc<LineIndex> {
-        self.db.file_lines(file_id)
-    }
-    pub fn world_symbols(&self, query: Query) -> Cancelable<Vec<(FileId, FileSymbol)>> {
-        /// Need to wrap Snapshot to provide `Clone` impl for `map_with`
-        struct Snap(salsa::Snapshot<db::RootDatabase>);
-        impl Clone for Snap {
-            fn clone(&self) -> Snap {
-                Snap(self.0.snapshot())
-            }
-        }
-        let buf: Vec<Arc<SymbolIndex>> = if query.libs {
-            let snap = Snap(self.db.snapshot());
-            self.db
-                .library_roots()
-                .par_iter()
-                .map_with(snap, |db, &lib_id| db.0.library_symbols(lib_id))
-                .collect()
-        } else {
-            let mut files = Vec::new();
-            for &root in self.db.local_roots().iter() {
-                let sr = self.db.source_root(root);
-                files.extend(sr.files.values().map(|&it| it))
-            }
-            let snap = Snap(self.db.snapshot());
-            files
-                .par_iter()
-                .map_with(snap, |db, &file_id| db.0.file_symbols(file_id))
-                .filter_map(|it| it.ok())
-                .collect()
-        };
-        Ok(query.search(&buf))
-    }
    /// This returns `Vec` because a module may be included from several places. We
    /// don't handle this case yet though, so the Vec has length at most one.
-    pub fn parent_module(&self, position: FilePosition) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    pub(crate) fn parent_module(
-        let descr = match source_binder::module_from_position(&*self.db, position)? {
+        &self,
+        position: FilePosition,
+    ) -> Cancelable<Vec<NavigationTarget>> {
+        let descr = match source_binder::module_from_position(self, position)? {
            None => return Ok(Vec::new()),
            Some(it) => it,
        };
-        let (file_id, decl) = match descr.parent_link_source(&*self.db) {
+        let (file_id, decl) = match descr.parent_link_source(self) {
            None => return Ok(Vec::new()),
            Some(it) => it,
        };
        let decl = decl.borrowed();
        let decl_name = decl.name().unwrap();
-        let sym = FileSymbol {
+        Ok(vec![NavigationTarget {
+            file_id,
            name: decl_name.text(),
-            node_range: decl_name.syntax().range(),
+            range: decl_name.syntax().range(),
            kind: MODULE,
-        };
+            ptr: None,
-        Ok(vec![(file_id, sym)])
+        }])
    }
    /// Returns `Vec` for the same reason as `parent_module`
-    pub fn crate_for(&self, file_id: FileId) -> Cancelable<Vec<CrateId>> {
+    pub(crate) fn crate_for(&self, file_id: FileId) -> Cancelable<Vec<CrateId>> {
-        let descr = match source_binder::module_from_file_id(&*self.db, file_id)? {
+        let descr = match source_binder::module_from_file_id(self, file_id)? {
            None => return Ok(Vec::new()),
            Some(it) => it,
        };
        let root = descr.crate_root();
-        let file_id = root.source().file_id();
+        let file_id = root.file_id();
-        let crate_graph = self.db.crate_graph();
+        let crate_graph = self.crate_graph();
        let crate_id = crate_graph.crate_id_for_crate_root(file_id);
        Ok(crate_id.into_iter().collect())
    }
-    pub fn crate_root(&self, crate_id: CrateId) -> FileId {
+    pub(crate) fn crate_root(&self, crate_id: CrateId) -> FileId {
-        self.db.crate_graph().crate_root(crate_id)
+        self.crate_graph().crate_root(crate_id)
    }
-    pub fn completions(&self, position: FilePosition) -> Cancelable<Option<Vec<CompletionItem>>> {
+    pub(crate) fn approximately_resolve_symbol(
-        let completions = completions(&self.db, position)?;
-        Ok(completions.map(|it| it.into()))
-    }
-    pub fn approximately_resolve_symbol(
        &self,
        position: FilePosition,
    ) -> Cancelable<Option<ReferenceResolution>> {
-        let file = self.db.source_file(position.file_id);
+        let file = self.source_file(position.file_id);
        let syntax = file.syntax();
        if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(syntax, position.offset) {
            let mut rr = ReferenceResolution::new(name_ref.syntax().range());
-            if let Some(fn_descr) = source_binder::function_from_child_node(
+            if let Some(fn_descr) =
-                &*self.db,
+                source_binder::function_from_child_node(self, position.file_id, name_ref.syntax())?
-                position.file_id,
+            {
-                name_ref.syntax(),
+                let scope = fn_descr.scopes(self);
-            )? {
-                let scope = fn_descr.scopes(&*self.db);
                // First try to resolve the symbol locally
                if let Some(entry) = scope.resolve_local_name(name_ref) {
-                    rr.add_resolution(
+                    rr.resolves_to.push(NavigationTarget {
-                        position.file_id,
+                        file_id: position.file_id,
-                        FileSymbol {
+                        name: entry.name().to_string().into(),
-                            name: entry.name().to_string().into(),
+                        range: entry.ptr().range(),
-                            node_range: entry.ptr().range(),
+                        kind: NAME,
-                            kind: NAME,
+                        ptr: None,
-                        },
+                    });
-                    );
                    return Ok(Some(rr));
                };
            }
            // If that fails try the index based approach.
-            for (file_id, symbol) in self.index_resolve(name_ref)? {
+            rr.resolves_to.extend(
-                rr.add_resolution(file_id, symbol);
+                self.index_resolve(name_ref)?
-            }
+                    .into_iter()
+                    .map(NavigationTarget::from_symbol),
+            );
            return Ok(Some(rr));
        }
        if let Some(name) = find_node_at_offset::<ast::Name>(syntax, position.offset) {
@@ -259,19 +177,21 @@ impl AnalysisImpl {
            if let Some(module) = name.syntax().parent().and_then(ast::Module::cast) {
                if module.has_semi() {
                    if let Some(child_module) =
-                        source_binder::module_from_declaration(&*self.db, position.file_id, module)?
+                        source_binder::module_from_declaration(self, position.file_id, module)?
                    {
-                        let file_id = child_module.source().file_id();
+                        let file_id = child_module.file_id();
                        let name = match child_module.name() {
                            Some(name) => name.to_string().into(),
                            None => "".into(),
                        };
-                        let symbol = FileSymbol {
+                        let symbol = NavigationTarget {
+                            file_id,
                            name,
-                            node_range: TextRange::offset_len(0.into(), 0.into()),
+                            range: TextRange::offset_len(0.into(), 0.into()),
                            kind: MODULE,
+                            ptr: None,
                        };
-                        rr.add_resolution(file_id, symbol);
+                        rr.resolves_to.push(symbol);
                        return Ok(Some(rr));
                    }
                }
@@ -280,10 +200,13 @@ impl AnalysisImpl {
        Ok(None)
    }
-    pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
+    pub(crate) fn find_all_refs(
-        let file = self.db.source_file(position.file_id);
+        &self,
+        position: FilePosition,
+    ) -> Cancelable<Vec<(FileId, TextRange)>> {
+        let file = self.source_file(position.file_id);
        // Find the binding associated with the offset
-        let (binding, descr) = match find_binding(&self.db, &file, position)? {
+        let (binding, descr) = match find_binding(self, &file, position)? {
            None => return Ok(Vec::new()),
            Some(it) => it,
        };
@@ -295,7 +218,7 @@ impl AnalysisImpl {
            .collect::<Vec<_>>();
        ret.extend(
            descr
-                .scopes(&*self.db)
+                .scopes(self)
                .find_all_refs(binding)
                .into_iter()
                .map(|ref_desc| (position.file_id, ref_desc.range)),
@@ -333,9 +256,8 @@ impl AnalysisImpl {
            Ok(Some((binding, descr)))
        }
    }
-    pub fn doc_text_for(&self, file_id: FileId, symbol: FileSymbol) -> Cancelable<Option<String>> {
+    pub(crate) fn doc_text_for(&self, nav: NavigationTarget) -> Cancelable<Option<String>> {
-        let file = self.db.source_file(file_id);
+        let result = match (nav.description(self), nav.docs(self)) {
-        let result = match (symbol.description(&file), symbol.docs(&file)) {
            (Some(desc), Some(docs)) => {
                Some("```rust\n".to_string() + &*desc + "\n```\n\n" + &*docs)
            }
@@ -347,8 +269,8 @@ impl AnalysisImpl {
        Ok(result)
    }
-    pub fn diagnostics(&self, file_id: FileId) -> Cancelable<Vec<Diagnostic>> {
+    pub(crate) fn diagnostics(&self, file_id: FileId) -> Cancelable<Vec<Diagnostic>> {
-        let syntax = self.db.source_file(file_id);
+        let syntax = self.source_file(file_id);
        let mut res = ra_editor::diagnostics(&syntax)
            .into_iter()
@@ -359,9 +281,9 @@ impl AnalysisImpl {
                fix: d.fix.map(|fix| SourceChange::from_local_edit(file_id, fix)),
            })
            .collect::<Vec<_>>();
-        if let Some(m) = source_binder::module_from_file_id(&*self.db, file_id)? {
+        if let Some(m) = source_binder::module_from_file_id(self, file_id)? {
-            for (name_node, problem) in m.problems(&*self.db) {
+            for (name_node, problem) in m.problems(self) {
-                let source_root = self.db.file_source_root(file_id);
+                let source_root = self.file_source_root(file_id);
                let diag = match problem {
                    Problem::UnresolvedModule { candidate } => {
                        let create_file = FileSystemEdit::CreateFile {
@@ -411,29 +333,19 @@ impl AnalysisImpl {
        Ok(res)
    }
-    pub fn assists(&self, frange: FileRange) -> Vec<SourceChange> {
+    pub(crate) fn assists(&self, frange: FileRange) -> Vec<SourceChange> {
-        let file = self.file_syntax(frange.file_id);
+        let file = self.source_file(frange.file_id);
-        let offset = frange.range.start();
+        assists::assists(&file, frange.range)
-        let actions = vec![
-            ra_editor::flip_comma(&file, offset).map(|f| f()),
-            ra_editor::add_derive(&file, offset).map(|f| f()),
-            ra_editor::add_impl(&file, offset).map(|f| f()),
-            ra_editor::make_pub_crate(&file, offset).map(|f| f()),
-            ra_editor::introduce_variable(&file, frange.range).map(|f| f()),
-        ];
-        actions
            .into_iter()
-            .filter_map(|local_edit| {
+            .map(|local_edit| SourceChange::from_local_edit(frange.file_id, local_edit))
-                Some(SourceChange::from_local_edit(frange.file_id, local_edit?))
-            })
            .collect()
    }
-    pub fn resolve_callable(
+    pub(crate) fn resolve_callable(
        &self,
        position: FilePosition,
    ) -> Cancelable<Option<(FnSignatureInfo, Option<usize>)>> {
-        let file = self.db.source_file(position.file_id);
+        let file = self.source_file(position.file_id);
        let syntax = file.syntax();
        // Find the calling expression and it's NameRef
@@ -442,53 +354,55 @@ impl AnalysisImpl {
        // Resolve the function's NameRef (NOTE: this isn't entirely accurate).
        let file_symbols = self.index_resolve(name_ref)?;
-        for (fn_file_id, fs) in file_symbols {
+        for symbol in file_symbols {
-            if fs.kind == FN_DEF {
+            if symbol.ptr.kind() == FN_DEF {
-                let fn_file = self.db.source_file(fn_file_id);
+                let fn_file = self.source_file(symbol.file_id);
-                if let Some(fn_def) = find_node_at_offset(fn_file.syntax(), fs.node_range.start()) {
+                let fn_def = symbol.ptr.resolve(&fn_file);
-                    let descr = ctry!(source_binder::function_from_source(
+                let fn_def = ast::FnDef::cast(fn_def.borrowed()).unwrap();
-                        &*self.db, fn_file_id, fn_def
+                let descr = ctry!(source_binder::function_from_source(
-                    )?);
+                    self,
-                    if let Some(descriptor) = descr.signature_info(&*self.db) {
+                    symbol.file_id,
-                        // If we have a calling expression let's find which argument we are on
+                    fn_def
-                        let mut current_parameter = None;
+                )?);
+                if let Some(descriptor) = descr.signature_info(self) {
-                        let num_params = descriptor.params.len();
+                    // If we have a calling expression let's find which argument we are on
-                        let has_self = fn_def.param_list().and_then(|l| l.self_param()).is_some();
+                    let mut current_parameter = None;
-                        if num_params == 1 {
+                    let num_params = descriptor.params.len();
-                            if !has_self {
+                    let has_self = fn_def.param_list().and_then(|l| l.self_param()).is_some();
-                                current_parameter = Some(0);
-                            }
+                    if num_params == 1 {
-                        } else if num_params > 1 {
+                        if !has_self {
-                            // Count how many parameters into the call we are.
+                            current_parameter = Some(0);
-                            // TODO: This is best effort for now and should be fixed at some point.
-                            // It may be better to see where we are in the arg_list and then check
-                            // where offset is in that list (or beyond).
-                            // Revisit this after we get documentation comments in.
-                            if let Some(ref arg_list) = calling_node.arg_list() {
-                                let start = arg_list.syntax().range().start();
-                                let range_search = TextRange::from_to(start, position.offset);
-                                let mut commas: usize = arg_list
-                                    .syntax()
-                                    .text()
-                                    .slice(range_search)
-                                    .to_string()
-                                    .matches(',')
-                                    .count();
-                                // If we have a method call eat the first param since it's just self.
-                                if has_self {
-                                    commas += 1;
-                                }
-                                current_parameter = Some(commas);
-                            }
                        }
+                    } else if num_params > 1 {
+                        // Count how many parameters into the call we are.
+                        // TODO: This is best effort for now and should be fixed at some point.
+                        // It may be better to see where we are in the arg_list and then check
+                        // where offset is in that list (or beyond).
+                        // Revisit this after we get documentation comments in.
+                        if let Some(ref arg_list) = calling_node.arg_list() {
+                            let start = arg_list.syntax().range().start();
+                            let range_search = TextRange::from_to(start, position.offset);
+                            let mut commas: usize = arg_list
+                                .syntax()
+                                .text()
+                                .slice(range_search)
+                                .to_string()
+                                .matches(',')
+                                .count();
+                            // If we have a method call eat the first param since it's just self.
+                            if has_self {
+                                commas += 1;
+                            }
-                        return Ok(Some((descriptor, current_parameter)));
+                            current_parameter = Some(commas);
+                        }
                    }
+                    return Ok(Some((descriptor, current_parameter)));
                }
            }
        }
@@ -496,20 +410,20 @@ impl AnalysisImpl {
        Ok(None)
    }
-    pub fn type_of(&self, frange: FileRange) -> Cancelable<Option<String>> {
+    pub(crate) fn type_of(&self, frange: FileRange) -> Cancelable<Option<String>> {
-        let file = self.db.source_file(frange.file_id);
+        let file = self.source_file(frange.file_id);
        let syntax = file.syntax();
        let node = find_covering_node(syntax, frange.range);
        let parent_fn = ctry!(node.ancestors().find_map(FnDef::cast));
        let function = ctry!(source_binder::function_from_source(
-            &*self.db,
+            self,
            frange.file_id,
            parent_fn
        )?);
-        let infer = function.infer(&*self.db)?;
+        let infer = function.infer(self)?;
        Ok(infer.type_of_node(node).map(|t| t.to_string()))
    }
-    pub fn rename(
+    pub(crate) fn rename(
        &self,
        position: FilePosition,
        new_name: &str,
@@ -520,7 +434,7 @@ impl AnalysisImpl {
            .map(|(file_id, text_range)| SourceFileEdit {
                file_id: *file_id,
                edit: {
-                    let mut builder = ra_text_edit::TextEditBuilder::new();
+                    let mut builder = ra_text_edit::TextEditBuilder::default();
                    builder.replace(*text_range, new_name.into());
                    builder.finish()
                },
@@ -528,12 +442,12 @@ impl AnalysisImpl {
            .collect::<Vec<_>>();
        Ok(res)
    }
-    fn index_resolve(&self, name_ref: ast::NameRef) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    fn index_resolve(&self, name_ref: ast::NameRef) -> Cancelable<Vec<FileSymbol>> {
        let name = name_ref.text();
        let mut query = Query::new(name.to_string());
        query.exact();
        query.limit(4);
-        self.world_symbols(query)
+        crate::symbol_index::world_symbols(self, query)
    }
 }
@@ -592,3 +506,91 @@ impl<'a> FnCallNode<'a> {
        }
    }
 }
+impl NavigationTarget {
+    fn node(&self, db: &db::RootDatabase) -> Option<SyntaxNode> {
+        let source_file = db.source_file(self.file_id);
+        let source_file = source_file.syntax();
+        let node = source_file
+            .descendants()
+            .find(|node| node.kind() == self.kind && node.range() == self.range)?
+            .owned();
+        Some(node)
+    }
+    fn docs(&self, db: &db::RootDatabase) -> Option<String> {
+        let node = self.node(db)?;
+        let node = node.borrowed();
+        fn doc_comments<'a, N: ast::DocCommentsOwner<'a>>(node: N) -> Option<String> {
+            let comments = node.doc_comment_text();
+            if comments.is_empty() {
+                None
+            } else {
+                Some(comments)
+            }
+        }
+        visitor()
+            .visit(doc_comments::<ast::FnDef>)
+            .visit(doc_comments::<ast::StructDef>)
+            .visit(doc_comments::<ast::EnumDef>)
+            .visit(doc_comments::<ast::TraitDef>)
+            .visit(doc_comments::<ast::Module>)
+            .visit(doc_comments::<ast::TypeDef>)
+            .visit(doc_comments::<ast::ConstDef>)
+            .visit(doc_comments::<ast::StaticDef>)
+            .accept(node)?
+    }
+    /// Get a description of this node.
+    ///
+    /// e.g. `struct Name`, `enum Name`, `fn Name`
+    fn description(&self, db: &db::RootDatabase) -> Option<String> {
+        // TODO: After type inference is done, add type information to improve the output
+        let node = self.node(db)?;
+        let node = node.borrowed();
+        // TODO: Refactor to be have less repetition
+        visitor()
+            .visit(|node: ast::FnDef| {
+                let mut string = "fn ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::StructDef| {
+                let mut string = "struct ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::EnumDef| {
+                let mut string = "enum ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::TraitDef| {
+                let mut string = "trait ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::Module| {
+                let mut string = "mod ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::TypeDef| {
+                let mut string = "type ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::ConstDef| {
+                let mut string = "const ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .visit(|node: ast::StaticDef| {
+                let mut string = "static ".to_string();
+                node.name()?.syntax().text().push_to(&mut string);
+                Some(string)
+            })
+            .accept(node)?
+    }
+}
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index e56168510..ab935954c 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -1,6 +1,8 @@
-//! ra_analyzer crate is the brain of Rust analyzer. It relies on the `salsa`
+//! ra_analyzer crate provides "ide-centric" APIs for the rust-analyzer. What
-//! crate, which provides and incremental on-demand database of facts.
+//! powers this API are the `RootDatabase` struct, which defines a `salsa`
+//! database, and the `ra_hir` crate, where majority of the analysis happens.
+//! However, IDE specific bits of the analysis (most notably completion) happen
+//! in this crate.
 macro_rules! ctry {
    ($expr:expr) => {
        match $expr {
@@ -15,34 +17,34 @@ mod imp;
 mod completion;
 mod symbol_index;
 pub mod mock_analysis;
+mod runnables;
 mod extend_selection;
 mod syntax_highlighting;
-mod macros;
 use std::{fmt, sync::Arc};
 use rustc_hash::FxHashMap;
-use ra_syntax::{SourceFileNode, TextRange, TextUnit};
+use ra_syntax::{SourceFileNode, TextRange, TextUnit, SmolStr, SyntaxKind};
 use ra_text_edit::TextEdit;
 use rayon::prelude::*;
 use relative_path::RelativePathBuf;
+use salsa::ParallelDatabase;
-use crate::{
+use crate::symbol_index::{SymbolIndex, FileSymbol};
-    imp::{AnalysisHostImpl, AnalysisImpl},
-    symbol_index::SymbolIndex,
-};
-pub use crate::completion::{CompletionItem, CompletionItemKind, InsertText};
+pub use crate::{
+    completion::{CompletionItem, CompletionItemKind, InsertText},
+    runnables::{Runnable, RunnableKind},
+};
 pub use ra_editor::{
-    FileSymbol, Fold, FoldKind, HighlightedRange, LineIndex, Runnable, RunnableKind, StructureNode,
+    Fold, FoldKind, HighlightedRange, LineIndex, StructureNode, Severity
-    Severity
 };
 pub use hir::FnSignatureInfo;
 pub use ra_db::{
-    Canceled, Cancelable, FilePosition, FileRange,
+    Canceled, Cancelable, FilePosition, FileRange, LocalSyntaxPtr,
-    CrateGraph, CrateId, SourceRootId, FileId
+    CrateGraph, CrateId, SourceRootId, FileId, SyntaxDatabase, FilesDatabase
 };
 #[derive(Default)]
@@ -148,27 +150,6 @@ impl AnalysisChange {
    }
 }
-/// `AnalysisHost` stores the current state of the world.
-#[derive(Debug, Default)]
-pub struct AnalysisHost {
-    imp: AnalysisHostImpl,
-}
-impl AnalysisHost {
-    /// Returns a snapshot of the current state, which you can query for
-    /// semantic information.
-    pub fn analysis(&self) -> Analysis {
-        Analysis {
-            imp: self.imp.analysis(),
-        }
-    }
-    /// Applies changes to the current state of the world. If there are
-    /// outstanding snapshots, they will be canceled.
-    pub fn apply_change(&mut self, change: AnalysisChange) {
-        self.imp.apply_change(change)
-    }
-}
 #[derive(Debug)]
 pub struct SourceChange {
    pub label: String,
@@ -240,6 +221,45 @@ impl Query {
    }
 }
+/// `NavigationTarget` represents and element in the editor's UI whihc you can
+/// click on to navigate to a particular piece of code.
+///
+/// Typically, a `NavigationTarget` corresponds to some element in the source
+/// code, like a function or a struct, but this is not strictly required.
+#[derive(Debug)]
+pub struct NavigationTarget {
+    file_id: FileId,
+    name: SmolStr,
+    kind: SyntaxKind,
+    range: TextRange,
+    // Should be DefId ideally
+    ptr: Option<LocalSyntaxPtr>,
+}
+impl NavigationTarget {
+    fn from_symbol(symbol: FileSymbol) -> NavigationTarget {
+        NavigationTarget {
+            file_id: symbol.file_id,
+            name: symbol.name.clone(),
+            kind: symbol.ptr.kind(),
+            range: symbol.ptr.range(),
+            ptr: Some(symbol.ptr.clone()),
+        }
+    }
+    pub fn name(&self) -> &SmolStr {
+        &self.name
+    }
+    pub fn kind(&self) -> SyntaxKind {
+        self.kind
+    }
+    pub fn file_id(&self) -> FileId {
+        self.file_id
+    }
+    pub fn range(&self) -> TextRange {
+        self.range
+    }
+}
 /// Result of "goto def" query.
 #[derive(Debug)]
 pub struct ReferenceResolution {
@@ -248,7 +268,7 @@ pub struct ReferenceResolution {
    /// client where the reference was.
    pub reference_range: TextRange,
    /// What this reference resolves to.
-    pub resolves_to: Vec<(FileId, FileSymbol)>,
+    pub resolves_to: Vec<NavigationTarget>,
 }
 impl ReferenceResolution {
@@ -258,9 +278,26 @@ impl ReferenceResolution {
            resolves_to: Vec::new(),
        }
    }
+}
+/// `AnalysisHost` stores the current state of the world.
+#[derive(Debug, Default)]
+pub struct AnalysisHost {
+    db: db::RootDatabase,
+}
-    fn add_resolution(&mut self, file_id: FileId, symbol: FileSymbol) {
+impl AnalysisHost {
-        self.resolves_to.push((file_id, symbol))
+    /// Returns a snapshot of the current state, which you can query for
+    /// semantic information.
+    pub fn analysis(&self) -> Analysis {
+        Analysis {
+            db: self.db.snapshot(),
+        }
+    }
+    /// Applies changes to the current state of the world. If there are
+    /// outstanding snapshots, they will be canceled.
+    pub fn apply_change(&mut self, change: AnalysisChange) {
+        self.db.apply_change(change)
    }
 }
@@ -270,109 +307,146 @@ impl ReferenceResolution {
 /// `Analysis` are canceled (most method return `Err(Canceled)`).
 #[derive(Debug)]
 pub struct Analysis {
-    pub(crate) imp: AnalysisImpl,
+    db: salsa::Snapshot<db::RootDatabase>,
 }
 impl Analysis {
+    /// Gets the text of the source file.
    pub fn file_text(&self, file_id: FileId) -> Arc<String> {
-        self.imp.file_text(file_id)
+        self.db.file_text(file_id)
    }
+    /// Gets the syntax tree of the file.
    pub fn file_syntax(&self, file_id: FileId) -> SourceFileNode {
-        self.imp.file_syntax(file_id).clone()
+        self.db.source_file(file_id).clone()
    }
+    /// Gets the file's `LineIndex`: data structure to convert between absolute
+    /// offsets and line/column representation.
    pub fn file_line_index(&self, file_id: FileId) -> Arc<LineIndex> {
-        self.imp.file_line_index(file_id)
+        self.db.file_lines(file_id)
    }
+    /// Selects the next syntactic nodes encopasing the range.
    pub fn extend_selection(&self, frange: FileRange) -> TextRange {
-        extend_selection::extend_selection(&self.imp.db, frange)
+        extend_selection::extend_selection(&self.db, frange)
    }
+    /// Returns position of the mathcing brace (all types of braces are
+    /// supported).
    pub fn matching_brace(&self, file: &SourceFileNode, offset: TextUnit) -> Option<TextUnit> {
        ra_editor::matching_brace(file, offset)
    }
+    /// Returns a syntax tree represented as `String`, for debug purposes.
+    // FIXME: use a better name here.
    pub fn syntax_tree(&self, file_id: FileId) -> String {
-        let file = self.imp.file_syntax(file_id);
+        let file = self.db.source_file(file_id);
        ra_editor::syntax_tree(&file)
    }
+    /// Returns an edit to remove all newlines in the range, cleaning up minor
+    /// stuff like trailing commas.
    pub fn join_lines(&self, frange: FileRange) -> SourceChange {
-        let file = self.imp.file_syntax(frange.file_id);
+        let file = self.db.source_file(frange.file_id);
        SourceChange::from_local_edit(frange.file_id, ra_editor::join_lines(&file, frange.range))
    }
+    /// Returns an edit which should be applied when opening a new line, fixing
+    /// up minor stuff like continuing the comment.
    pub fn on_enter(&self, position: FilePosition) -> Option<SourceChange> {
-        let file = self.imp.file_syntax(position.file_id);
+        let file = self.db.source_file(position.file_id);
        let edit = ra_editor::on_enter(&file, position.offset)?;
-        let res = SourceChange::from_local_edit(position.file_id, edit);
+        Some(SourceChange::from_local_edit(position.file_id, edit))
-        Some(res)
    }
+    /// Returns an edit which should be applied after `=` was typed. Primaraly,
+    /// this works when adding `let =`.
+    // FIXME: use a snippet completion instead of this hack here.
    pub fn on_eq_typed(&self, position: FilePosition) -> Option<SourceChange> {
-        let file = self.imp.file_syntax(position.file_id);
+        let file = self.db.source_file(position.file_id);
-        Some(SourceChange::from_local_edit(
+        let edit = ra_editor::on_eq_typed(&file, position.offset)?;
-            position.file_id,
+        Some(SourceChange::from_local_edit(position.file_id, edit))
-            ra_editor::on_eq_typed(&file, position.offset)?,
-        ))
    }
+    /// Returns a tree representation of symbols in the file. Useful to draw a
+    /// file outline.
    pub fn file_structure(&self, file_id: FileId) -> Vec<StructureNode> {
-        let file = self.imp.file_syntax(file_id);
+        let file = self.db.source_file(file_id);
        ra_editor::file_structure(&file)
    }
+    /// Returns the set of folding ranges.
    pub fn folding_ranges(&self, file_id: FileId) -> Vec<Fold> {
-        let file = self.imp.file_syntax(file_id);
+        let file = self.db.source_file(file_id);
        ra_editor::folding_ranges(&file)
    }
-    pub fn symbol_search(&self, query: Query) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    /// Fuzzy searches for a symbol.
-        self.imp.world_symbols(query)
+    pub fn symbol_search(&self, query: Query) -> Cancelable<Vec<NavigationTarget>> {
+        let res = symbol_index::world_symbols(&*self.db, query)?
+            .into_iter()
+            .map(NavigationTarget::from_symbol)
+            .collect();
+        Ok(res)
    }
+    /// Resolves reference to definition, but does not gurantee correctness.
    pub fn approximately_resolve_symbol(
        &self,
        position: FilePosition,
    ) -> Cancelable<Option<ReferenceResolution>> {
-        self.imp.approximately_resolve_symbol(position)
+        self.db.approximately_resolve_symbol(position)
    }
+    /// Finds all usages of the reference at point.
    pub fn find_all_refs(&self, position: FilePosition) -> Cancelable<Vec<(FileId, TextRange)>> {
-        self.imp.find_all_refs(position)
+        self.db.find_all_refs(position)
    }
-    pub fn doc_text_for(&self, file_id: FileId, symbol: FileSymbol) -> Cancelable<Option<String>> {
+    /// Returns documentation string for a given target.
-        self.imp.doc_text_for(file_id, symbol)
+    pub fn doc_text_for(&self, nav: NavigationTarget) -> Cancelable<Option<String>> {
+        self.db.doc_text_for(nav)
    }
-    pub fn parent_module(&self, position: FilePosition) -> Cancelable<Vec<(FileId, FileSymbol)>> {
+    /// Returns a `mod name;` declaration whihc created the current module.
-        self.imp.parent_module(position)
+    pub fn parent_module(&self, position: FilePosition) -> Cancelable<Vec<NavigationTarget>> {
+        self.db.parent_module(position)
    }
+    /// Returns crates this file belongs too.
    pub fn crate_for(&self, file_id: FileId) -> Cancelable<Vec<CrateId>> {
-        self.imp.crate_for(file_id)
+        self.db.crate_for(file_id)
    }
+    /// Returns the root file of the given crate.
    pub fn crate_root(&self, crate_id: CrateId) -> Cancelable<FileId> {
-        Ok(self.imp.crate_root(crate_id))
+        Ok(self.db.crate_root(crate_id))
    }
+    /// Returns the set of possible targets to run for the current file.
    pub fn runnables(&self, file_id: FileId) -> Cancelable<Vec<Runnable>> {
-        let file = self.imp.file_syntax(file_id);
+        runnables::runnables(&*self.db, file_id)
-        Ok(ra_editor::runnables(&file))
    }
+    /// Computes syntax highlighting for the given file.
    pub fn highlight(&self, file_id: FileId) -> Cancelable<Vec<HighlightedRange>> {
-        syntax_highlighting::highlight(&*self.imp.db, file_id)
+        syntax_highlighting::highlight(&*self.db, file_id)
    }
+    /// Computes completions at the given position.
    pub fn completions(&self, position: FilePosition) -> Cancelable<Option<Vec<CompletionItem>>> {
-        self.imp.completions(position)
+        let completions = completion::completions(&self.db, position)?;
+        Ok(completions.map(|it| it.into()))
    }
+    /// Computes assists (aks code actons aka intentions) for the given
+    /// position.
    pub fn assists(&self, frange: FileRange) -> Cancelable<Vec<SourceChange>> {
-        Ok(self.imp.assists(frange))
+        Ok(self.db.assists(frange))
    }
+    /// Computes the set of diagnostics for the given file.
    pub fn diagnostics(&self, file_id: FileId) -> Cancelable<Vec<Diagnostic>> {
-        self.imp.diagnostics(file_id)
+        self.db.diagnostics(file_id)
    }
+    /// Computes parameter information for the given call expression.
    pub fn resolve_callable(
        &self,
        position: FilePosition,
    ) -> Cancelable<Option<(FnSignatureInfo, Option<usize>)>> {
-        self.imp.resolve_callable(position)
+        self.db.resolve_callable(position)
    }
+    /// Computes the type of the expression at the given position.
    pub fn type_of(&self, frange: FileRange) -> Cancelable<Option<String>> {
-        self.imp.type_of(frange)
+        self.db.type_of(frange)
    }
+    /// Returns the edit required to rename reference at the position to the new
+    /// name.
    pub fn rename(
        &self,
        position: FilePosition,
        new_name: &str,
    ) -> Cancelable<Vec<SourceFileEdit>> {
-        self.imp.rename(position, new_name)
+        self.db.rename(position, new_name)
    }
 }
diff --git a/crates/ra_analysis/src/macros.rs b/crates/ra_analysis/src/macros.rs
deleted file mode 100644
index b9feb7fad..000000000
--- a/crates/ra_analysis/src/macros.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-/// Begining of macro expansion.
-///
-/// This code should be moved out of ra_analysis into hir (?) ideally.
-use ra_syntax::{ast, AstNode, SourceFileNode, TextRange};
-use crate::{db::RootDatabase, FileId};
-pub(crate) fn expand(
-    _db: &RootDatabase,
-    _file_id: FileId,
-    macro_call: ast::MacroCall,
-) -> Option<MacroExpansion> {
-    let path = macro_call.path()?;
-    if path.qualifier().is_some() {
-        return None;
-    }
-    let name_ref = path.segment()?.name_ref()?;
-    if name_ref.text() != "ctry" {
-        return None;
-    }
-    let arg = macro_call.token_tree()?;
-    let text = format!(
-        r"
-        fn dummy() {{
-            match {} {{
-                None => return Ok(None),
-                Some(it) => it,
-            }}
-        }}",
-        arg.syntax().text()
-    );
-    let file = SourceFileNode::parse(&text);
-    let match_expr = file.syntax().descendants().find_map(ast::MatchExpr::cast)?;
-    let match_arg = match_expr.expr()?;
-    let ranges_map = vec![(arg.syntax().range(), match_arg.syntax().range())];
-    let res = MacroExpansion {
-        source_file: file,
-        ranges_map,
-    };
-    Some(res)
-}
-pub(crate) struct MacroExpansion {
-    pub(crate) source_file: SourceFileNode,
-    pub(crate) ranges_map: Vec<(TextRange, TextRange)>,
-}
-impl MacroExpansion {
-    pub(crate) fn source_file(&self) -> &SourceFileNode {
-        &self.source_file
-    }
-    pub(crate) fn map_range_back(&self, tgt_range: TextRange) -> Option<TextRange> {
-        for (s_range, t_range) in self.ranges_map.iter() {
-            if tgt_range.is_subrange(&t_range) {
-                let tgt_at_zero_range = tgt_range - tgt_range.start();
-                let tgt_range_offset = tgt_range.start() - t_range.start();
-                let src_range = tgt_at_zero_range + tgt_range_offset + s_range.start();
-                return Some(src_range);
-            }
-        }
-        None
-    }
-    pub(crate) fn map_range_forward(&self, src_range: TextRange) -> Option<TextRange> {
-        for (s_range, t_range) in self.ranges_map.iter() {
-            if src_range.is_subrange(&s_range) {
-                let src_at_zero_range = src_range - src_range.start();
-                let src_range_offset = src_range.start() - s_range.start();
-                let src_range = src_at_zero_range + src_range_offset + t_range.start();
-                return Some(src_range);
-            }
-        }
-        None
-    }
-}
diff --git a/crates/ra_analysis/src/runnables.rs b/crates/ra_analysis/src/runnables.rs
new file mode 100644
index 000000000..474267605
--- /dev/null
+++ b/crates/ra_analysis/src/runnables.rs
@@ -0,0 +1,86 @@
+use itertools::Itertools;
+use ra_syntax::{
+    ast::{self, AstNode, NameOwner, ModuleItemOwner},
+    TextRange, SyntaxNodeRef,
+};
+use ra_db::{Cancelable, SyntaxDatabase};
+use crate::{db::RootDatabase, FileId};
+#[derive(Debug)]
+pub struct Runnable {
+    pub range: TextRange,
+    pub kind: RunnableKind,
+}
+#[derive(Debug)]
+pub enum RunnableKind {
+    Test { name: String },
+    TestMod { path: String },
+    Bin,
+}
+pub(crate) fn runnables(db: &RootDatabase, file_id: FileId) -> Cancelable<Vec<Runnable>> {
+    let source_file = db.source_file(file_id);
+    let res = source_file
+        .syntax()
+        .descendants()
+        .filter_map(|i| runnable(db, file_id, i))
+        .collect();
+    Ok(res)
+}
+fn runnable(db: &RootDatabase, file_id: FileId, item: SyntaxNodeRef) -> Option<Runnable> {
+    if let Some(fn_def) = ast::FnDef::cast(item) {
+        runnable_fn(fn_def)
+    } else if let Some(m) = ast::Module::cast(item) {
+        runnable_mod(db, file_id, m)
+    } else {
+        None
+    }
+}
+fn runnable_fn(fn_def: ast::FnDef) -> Option<Runnable> {
+    let name = fn_def.name()?.text();
+    let kind = if name == "main" {
+        RunnableKind::Bin
+    } else if fn_def.has_atom_attr("test") {
+        RunnableKind::Test {
+            name: name.to_string(),
+        }
+    } else {
+        return None;
+    };
+    Some(Runnable {
+        range: fn_def.syntax().range(),
+        kind,
+    })
+}
+fn runnable_mod(db: &RootDatabase, file_id: FileId, module: ast::Module) -> Option<Runnable> {
+    let has_test_function = module
+        .item_list()?
+        .items()
+        .filter_map(|it| match it {
+            ast::ModuleItem::FnDef(it) => Some(it),
+            _ => None,
+        })
+        .any(|f| f.has_atom_attr("test"));
+    if !has_test_function {
+        return None;
+    }
+    let range = module.syntax().range();
+    let module =
+        hir::source_binder::module_from_child_node(db, file_id, module.syntax()).ok()??;
+    let path = module
+        .path_to_root()
+        .into_iter()
+        .rev()
+        .into_iter()
+        .filter_map(|it| it.name().map(Clone::clone))
+        .join("::");
+    Some(Runnable {
+        range,
+        kind: RunnableKind::TestMod { path },
+    })
+}
diff --git a/crates/ra_analysis/src/symbol_index.rs b/crates/ra_analysis/src/symbol_index.rs
index e5bdf0aa1..e2b1c88fe 100644
--- a/crates/ra_analysis/src/symbol_index.rs
+++ b/crates/ra_analysis/src/symbol_index.rs
@@ -1,24 +1,48 @@
+//! This module handles fuzzy-searching of functions, structs and other symbols
+//! by name across the whole workspace and dependencies.
+//!
+//! It works by building an incrementally-updated text-search index of all
+//! symbols. The backbone of the index is the **awesome** `fst` crate by
+//! @BurntSushi.
+//!
+//! In a nutshell, you give a set of strings to the `fst`, and it builds a
+//! finite state machine describing this set of strtings. The strings which
+//! could fuzzy-match a pattern can also be described by a finite state machine.
+//! What is freakingly cool is that you can now traverse both state machines in
+//! lock-step to enumerate the strings which are both in the input set and
+//! fuzz-match the query. Or, more formally, given two langauges described by
+//! fsts, one can build an product fst which describes the intersection of the
+//! languages.
+//!
+//! `fst` does not support cheap updating of the index, but it supports unioning
+//! of state machines. So, to account for changing source code, we build an fst
+//! for each library (which is assumed to never change) and an fst for each rust
+//! file in the current workspace, and run a query aginst the union of all
+//! thouse fsts.
 use std::{
+    cmp::Ordering,
    hash::{Hash, Hasher},
    sync::Arc,
 };
 use fst::{self, Streamer};
-use ra_editor::{self, FileSymbol};
 use ra_syntax::{
-    SourceFileNode,
+    SyntaxNodeRef, SourceFileNode, SmolStr,
+    algo::{visit::{visitor, Visitor}, find_covering_node},
    SyntaxKind::{self, *},
+    ast::{self, NameOwner},
 };
-use ra_db::{SyntaxDatabase, SourceRootId};
+use ra_db::{SourceRootId, FilesDatabase, LocalSyntaxPtr};
+use salsa::ParallelDatabase;
 use rayon::prelude::*;
 use crate::{
-    Cancelable,
+    Cancelable, FileId, Query,
-    FileId, Query,
+    db::RootDatabase,
 };
 salsa::query_group! {
-    pub(crate) trait SymbolsDatabase: SyntaxDatabase {
+    pub(crate) trait SymbolsDatabase: hir::db::HirDatabase {
        fn file_symbols(file_id: FileId) -> Cancelable<Arc<SymbolIndex>> {
            type FileSymbolsQuery;
        }
@@ -29,15 +53,60 @@ salsa::query_group! {
    }
 }
-fn file_symbols(db: &impl SyntaxDatabase, file_id: FileId) -> Cancelable<Arc<SymbolIndex>> {
+fn file_symbols(db: &impl SymbolsDatabase, file_id: FileId) -> Cancelable<Arc<SymbolIndex>> {
    db.check_canceled()?;
-    let syntax = db.source_file(file_id);
+    let source_file = db.source_file(file_id);
-    Ok(Arc::new(SymbolIndex::for_file(file_id, syntax)))
+    let mut symbols = source_file
+        .syntax()
+        .descendants()
+        .filter_map(to_symbol)
+        .map(move |(name, ptr)| FileSymbol { name, ptr, file_id })
+        .collect::<Vec<_>>();
+    for (name, text_range) in hir::source_binder::macro_symbols(db, file_id)? {
+        let node = find_covering_node(source_file.syntax(), text_range);
+        let ptr = LocalSyntaxPtr::new(node);
+        symbols.push(FileSymbol { file_id, name, ptr })
+    }
+    Ok(Arc::new(SymbolIndex::new(symbols)))
+}
+pub(crate) fn world_symbols(db: &RootDatabase, query: Query) -> Cancelable<Vec<FileSymbol>> {
+    /// Need to wrap Snapshot to provide `Clone` impl for `map_with`
+    struct Snap(salsa::Snapshot<RootDatabase>);
+    impl Clone for Snap {
+        fn clone(&self) -> Snap {
+            Snap(self.0.snapshot())
+        }
+    }
+    let buf: Vec<Arc<SymbolIndex>> = if query.libs {
+        let snap = Snap(db.snapshot());
+        db.library_roots()
+            .par_iter()
+            .map_with(snap, |db, &lib_id| db.0.library_symbols(lib_id))
+            .collect()
+    } else {
+        let mut files = Vec::new();
+        for &root in db.local_roots().iter() {
+            let sr = db.source_root(root);
+            files.extend(sr.files.values().map(|&it| it))
+        }
+        let snap = Snap(db.snapshot());
+        files
+            .par_iter()
+            .map_with(snap, |db, &file_id| db.0.file_symbols(file_id))
+            .filter_map(|it| it.ok())
+            .collect()
+    };
+    Ok(query.search(&buf))
 }
 #[derive(Default, Debug)]
 pub(crate) struct SymbolIndex {
-    symbols: Vec<(FileId, FileSymbol)>,
+    symbols: Vec<FileSymbol>,
    map: fst::Map,
 }
@@ -56,6 +125,17 @@ impl Hash for SymbolIndex {
 }
 impl SymbolIndex {
+    fn new(mut symbols: Vec<FileSymbol>) -> SymbolIndex {
+        fn cmp(s1: &FileSymbol, s2: &FileSymbol) -> Ordering {
+            unicase::Ascii::new(s1.name.as_str()).cmp(&unicase::Ascii::new(s2.name.as_str()))
+        }
+        symbols.par_sort_by(cmp);
+        symbols.dedup_by(|s1, s2| cmp(s1, s2) == Ordering::Equal);
+        let names = symbols.iter().map(|it| it.name.as_str().to_lowercase());
+        let map = fst::Map::from_iter(names.into_iter().zip(0u64..)).unwrap();
+        SymbolIndex { symbols, map }
+    }
    pub(crate) fn len(&self) -> usize {
        self.symbols.len()
    }
@@ -63,29 +143,21 @@ impl SymbolIndex {
    pub(crate) fn for_files(
        files: impl ParallelIterator<Item = (FileId, SourceFileNode)>,
    ) -> SymbolIndex {
-        let mut symbols = files
+        let symbols = files
            .flat_map(|(file_id, file)| {
-                ra_editor::file_symbols(&file)
+                file.syntax()
-                    .into_iter()
+                    .descendants()
-                    .map(move |symbol| (symbol.name.as_str().to_lowercase(), (file_id, symbol)))
+                    .filter_map(to_symbol)
+                    .map(move |(name, ptr)| FileSymbol { name, ptr, file_id })
                    .collect::<Vec<_>>()
            })
            .collect::<Vec<_>>();
-        symbols.par_sort_by(|s1, s2| s1.0.cmp(&s2.0));
+        SymbolIndex::new(symbols)
-        symbols.dedup_by(|s1, s2| s1.0 == s2.0);
-        let (names, symbols): (Vec<String>, Vec<(FileId, FileSymbol)>) =
-            symbols.into_iter().unzip();
-        let map = fst::Map::from_iter(names.into_iter().zip(0u64..)).unwrap();
-        SymbolIndex { symbols, map }
-    }
-    pub(crate) fn for_file(file_id: FileId, file: SourceFileNode) -> SymbolIndex {
-        SymbolIndex::for_files(rayon::iter::once((file_id, file)))
    }
 }
 impl Query {
-    pub(crate) fn search(self, indices: &[Arc<SymbolIndex>]) -> Vec<(FileId, FileSymbol)> {
+    pub(crate) fn search(self, indices: &[Arc<SymbolIndex>]) -> Vec<FileSymbol> {
        let mut op = fst::map::OpBuilder::new();
        for file_symbols in indices.iter() {
            let automaton = fst::automaton::Subsequence::new(&self.lowercased);
@@ -101,14 +173,14 @@ impl Query {
                let file_symbols = &indices[indexed_value.index];
                let idx = indexed_value.value as usize;
-                let (file_id, symbol) = &file_symbols.symbols[idx];
+                let symbol = &file_symbols.symbols[idx];
-                if self.only_types && !is_type(symbol.kind) {
+                if self.only_types && !is_type(symbol.ptr.kind()) {
                    continue;
                }
                if self.exact && symbol.name != self.query {
                    continue;
                }
-                res.push((*file_id, symbol.clone()));
+                res.push(symbol.clone());
            }
        }
        res
@@ -121,3 +193,30 @@ fn is_type(kind: SyntaxKind) -> bool {
        _ => false,
    }
 }
+/// The actual data that is stored in the index. It should be as compact as
+/// possible.
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub(crate) struct FileSymbol {
+    pub(crate) file_id: FileId,
+    pub(crate) name: SmolStr,
+    pub(crate) ptr: LocalSyntaxPtr,
+}
+fn to_symbol(node: SyntaxNodeRef) -> Option<(SmolStr, LocalSyntaxPtr)> {
+    fn decl<'a, N: NameOwner<'a>>(node: N) -> Option<(SmolStr, LocalSyntaxPtr)> {
+        let name = node.name()?.text();
+        let ptr = LocalSyntaxPtr::new(node.syntax());
+        Some((name, ptr))
+    }
+    visitor()
+        .visit(decl::<ast::FnDef>)
+        .visit(decl::<ast::StructDef>)
+        .visit(decl::<ast::EnumDef>)
+        .visit(decl::<ast::TraitDef>)
+        .visit(decl::<ast::Module>)
+        .visit(decl::<ast::TypeDef>)
+        .visit(decl::<ast::ConstDef>)
+        .visit(decl::<ast::StaticDef>)
+        .accept(node)?
+}
diff --git a/crates/ra_analysis/src/syntax_highlighting.rs b/crates/ra_analysis/src/syntax_highlighting.rs
index 38219da71..35e153ca0 100644
--- a/crates/ra_analysis/src/syntax_highlighting.rs
+++ b/crates/ra_analysis/src/syntax_highlighting.rs
@@ -9,19 +9,19 @@ use crate::{
 pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Cancelable<Vec<HighlightedRange>> {
    let source_file = db.source_file(file_id);
-    let mut res = ra_editor::highlight(&source_file);
+    let mut res = ra_editor::highlight(source_file.syntax());
    for macro_call in source_file
        .syntax()
        .descendants()
        .filter_map(ast::MacroCall::cast)
    {
-        if let Some(exp) = crate::macros::expand(db, file_id, macro_call) {
+        if let Some((off, exp)) = hir::MacroDef::ast_expand(macro_call) {
-            let mapped_ranges = ra_editor::highlight(exp.source_file())
+            let mapped_ranges = ra_editor::highlight(exp.syntax().borrowed())
                .into_iter()
                .filter_map(|r| {
                    let mapped_range = exp.map_range_back(r.range)?;
                    let res = HighlightedRange {
-                        range: mapped_range,
+                        range: mapped_range + off,
                        tag: r.tag,
                    };
                    Some(res)
@@ -43,8 +43,9 @@ mod tests {
            "
            fn main() {
                ctry!({ let x = 92; x});
+                vec![{ let x = 92; x}];
            }
-        ",
+            ",
        );
        let highlights = analysis.highlight(file_id).unwrap();
        assert_eq_dbg(
@@ -53,10 +54,39 @@ mod tests {
                HighlightedRange { range: [41; 46), tag: "macro" },
                HighlightedRange { range: [49; 52), tag: "keyword" },
                HighlightedRange { range: [57; 59), tag: "literal" },
+                HighlightedRange { range: [82; 86), tag: "macro" },
+                HighlightedRange { range: [89; 92), tag: "keyword" },
+                HighlightedRange { range: [97; 99), tag: "literal" },
                HighlightedRange { range: [49; 52), tag: "keyword" },
                HighlightedRange { range: [53; 54), tag: "function" },
                HighlightedRange { range: [57; 59), tag: "literal" },
-                HighlightedRange { range: [61; 62), tag: "text" }]"#,
+                HighlightedRange { range: [61; 62), tag: "text" },
+                HighlightedRange { range: [89; 92), tag: "keyword" },
+                HighlightedRange { range: [93; 94), tag: "function" },
+                HighlightedRange { range: [97; 99), tag: "literal" },
+                HighlightedRange { range: [101; 102), tag: "text" }]"#,
+            &highlights,
+        )
+    }
+    // FIXME: this test is not really necessary: artifact of the inital hacky
+    // macros implementation.
+    #[test]
+    fn highlight_query_group_macro() {
+        let (analysis, file_id) = single_file(
+            "
+            salsa::query_group! {
+                pub trait HirDatabase: SyntaxDatabase {}
+            }
+            ",
+        );
+        let highlights = analysis.highlight(file_id).unwrap();
+        assert_eq_dbg(
+            r#"[HighlightedRange { range: [20; 32), tag: "macro" },
+                HighlightedRange { range: [13; 18), tag: "text" },
+                HighlightedRange { range: [51; 54), tag: "keyword" },
+                HighlightedRange { range: [55; 60), tag: "keyword" },
+                HighlightedRange { range: [61; 72), tag: "function" }]"#,
            &highlights,
        )
    }
diff --git a/crates/ra_analysis/tests/tests.rs b/crates/ra_analysis/tests/test/main.rs
index a314fbc40..bfdf8aef2 100644
--- a/crates/ra_analysis/tests/tests.rs
+++ b/crates/ra_analysis/tests/test/main.rs
@@ -1,9 +1,12 @@
+mod runnables;
+mod type_of;
 use ra_syntax::TextRange;
 use test_utils::{assert_eq_dbg, assert_eq_text};
 use ra_analysis::{
    mock_analysis::{analysis_and_position, single_file, single_file_with_position, MockAnalysis},
-    AnalysisChange, CrateGraph, FileId, FnSignatureInfo,
+    AnalysisChange, CrateGraph, FileId, FnSignatureInfo, Query
 };
 fn get_signature(text: &str) -> (FnSignatureInfo, Option<usize>) {
@@ -25,7 +28,7 @@ fn approximate_resolve_works_in_items() {
    assert_eq_dbg(
        r#"ReferenceResolution {
            reference_range: [23; 26),
-            resolves_to: [(FileId(1), FileSymbol { name: "Foo", node_range: [0; 11), kind: STRUCT_DEF })]
+            resolves_to: [NavigationTarget { file_id: FileId(1), name: "Foo", kind: STRUCT_DEF, range: [0; 11), ptr: Some(LocalSyntaxPtr { range: [0; 11), kind: STRUCT_DEF }) }]
        }"#,
        &symbols,
    );
@@ -46,7 +49,7 @@ fn test_resolve_module() {
    assert_eq_dbg(
        r#"ReferenceResolution {
            reference_range: [4; 7),
-            resolves_to: [(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]
+            resolves_to: [NavigationTarget { file_id: FileId(2), name: "foo", kind: MODULE, range: [0; 0), ptr: None }]
        }"#,
        &symbols,
    );
@@ -64,7 +67,7 @@ fn test_resolve_module() {
    assert_eq_dbg(
        r#"ReferenceResolution {
            reference_range: [4; 7),
-            resolves_to: [(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]
+            resolves_to: [NavigationTarget { file_id: FileId(2), name: "foo", kind: MODULE, range: [0; 0), ptr: None }]
        }"#,
        &symbols,
    );
@@ -107,7 +110,7 @@ fn test_resolve_parent_module() {
    );
    let symbols = analysis.parent_module(pos).unwrap();
    assert_eq_dbg(
-        r#"[(FileId(1), FileSymbol { name: "foo", node_range: [4; 7), kind: MODULE })]"#,
+        r#"[NavigationTarget { file_id: FileId(1), name: "foo", kind: MODULE, range: [4; 7), ptr: None }]"#,
        &symbols,
    );
 }
@@ -126,7 +129,7 @@ fn test_resolve_parent_module_for_inline() {
    );
    let symbols = analysis.parent_module(pos).unwrap();
    assert_eq_dbg(
-        r#"[(FileId(1), FileSymbol { name: "bar", node_range: [18; 21), kind: MODULE })]"#,
+        r#"[NavigationTarget { file_id: FileId(1), name: "bar", kind: MODULE, range: [18; 21), ptr: None }]"#,
        &symbols,
    );
 }
@@ -528,10 +531,11 @@ fn test_rename_for_mut_param() {
    }"#,
    );
 }
 fn test_rename(text: &str, new_name: &str, expected: &str) {
    let (analysis, position) = single_file_with_position(text);
    let edits = analysis.rename(position, new_name).unwrap();
-    let mut text_edit_bulder = ra_text_edit::TextEditBuilder::new();
+    let mut text_edit_bulder = ra_text_edit::TextEditBuilder::default();
    let mut file_id: Option<FileId> = None;
    for edit in edits {
        file_id = Some(edit.file_id);
@@ -544,3 +548,19 @@ fn test_rename(text: &str, new_name: &str, expected: &str) {
        .apply(&*analysis.file_text(file_id.unwrap()));
    assert_eq_text!(expected, &*result);
 }
+#[test]
+fn world_symbols_include_stuff_from_macros() {
+    let (analysis, _) = single_file(
+        "
+salsa::query_group! {
+pub trait HirDatabase: SyntaxDatabase {}
+}
+    ",
+    );
+    let mut symbols = analysis.symbol_search(Query::new("Hir".into())).unwrap();
+    let s = symbols.pop().unwrap();
+    assert_eq!(s.name(), "HirDatabase");
+    assert_eq!(s.range(), TextRange::from_to(33.into(), 44.into()));
+}
diff --git a/crates/ra_analysis/tests/test/runnables.rs b/crates/ra_analysis/tests/test/runnables.rs
new file mode 100644
index 000000000..e6e0afbc3
--- /dev/null
+++ b/crates/ra_analysis/tests/test/runnables.rs
@@ -0,0 +1,109 @@
+use test_utils::assert_eq_dbg;
+use ra_analysis::mock_analysis::analysis_and_position;
+#[test]
+fn test_runnables() {
+    let (analysis, pos) = analysis_and_position(
+        r#"
+        //- /lib.rs
+        <|> //empty
+        fn main() {}
+        #[test]
+        fn test_foo() {}
+        #[test]
+        #[ignore]
+        fn test_foo() {}
+        "#,
+    );
+    let runnables = analysis.runnables(pos.file_id).unwrap();
+    assert_eq_dbg(
+        r#"[Runnable { range: [1; 21), kind: Bin },
+                Runnable { range: [22; 46), kind: Test { name: "test_foo" } },
+                Runnable { range: [47; 81), kind: Test { name: "test_foo" } }]"#,
+        &runnables,
+    )
+}
+#[test]
+fn test_runnables_module() {
+    let (analysis, pos) = analysis_and_position(
+        r#"
+        //- /lib.rs
+        <|> //empty
+        mod test_mod {
+            #[test]
+            fn test_foo1() {}
+        }
+        "#,
+    );
+    let runnables = analysis.runnables(pos.file_id).unwrap();
+    assert_eq_dbg(
+        r#"[Runnable { range: [1; 59), kind: TestMod { path: "test_mod" } },
+                Runnable { range: [28; 57), kind: Test { name: "test_foo1" } }]"#,
+        &runnables,
+    )
+}
+#[test]
+fn test_runnables_one_depth_layer_module() {
+    let (analysis, pos) = analysis_and_position(
+        r#"
+        //- /lib.rs
+        <|> //empty
+        mod foo {
+            mod test_mod {
+                #[test]
+                fn test_foo1() {}
+            }
+        }
+        "#,
+    );
+    let runnables = analysis.runnables(pos.file_id).unwrap();
+    assert_eq_dbg(
+        r#"[Runnable { range: [23; 85), kind: TestMod { path: "foo::test_mod" } },
+                Runnable { range: [46; 79), kind: Test { name: "test_foo1" } }]"#,
+        &runnables,
+    )
+}
+#[test]
+fn test_runnables_multiple_depth_module() {
+    let (analysis, pos) = analysis_and_position(
+        r#"
+        //- /lib.rs
+        <|> //empty
+        mod foo {
+            mod bar {
+                mod test_mod {
+                    #[test]
+                    fn test_foo1() {}
+                }
+            }
+        }
+        "#,
+    );
+    let runnables = analysis.runnables(pos.file_id).unwrap();
+    assert_eq_dbg(
+        r#"[Runnable { range: [41; 115), kind: TestMod { path: "foo::bar::test_mod" } },
+                Runnable { range: [68; 105), kind: Test { name: "test_foo1" } }]"#,
+        &runnables,
+    )
+}
+#[test]
+fn test_runnables_no_test_function_in_module() {
+    let (analysis, pos) = analysis_and_position(
+        r#"
+        //- /lib.rs
+        <|> //empty
+        mod test_mod {
+            fn foo1() {}
+        }
+        "#,
+    );
+    let runnables = analysis.runnables(pos.file_id).unwrap();
+    assert_eq_dbg(r#"[]"#, &runnables)
+}
diff --git a/crates/ra_analysis/tests/test/type_of.rs b/crates/ra_analysis/tests/test/type_of.rs
new file mode 100644
index 000000000..9d15b52a8
--- /dev/null
+++ b/crates/ra_analysis/tests/test/type_of.rs
@@ -0,0 +1,77 @@
+use ra_analysis::mock_analysis::single_file_with_range;
+#[test]
+fn test_type_of_for_function() {
+    let (analysis, range) = single_file_with_range(
+        "
+        pub fn foo() -> u32 { 1 };
+        fn main() {
+            let foo_test = <|>foo()<|>;
+        }
+        ",
+    );
+    let type_name = analysis.type_of(range).unwrap().unwrap();
+    assert_eq!("u32", &type_name);
+}
+// FIXME: improve type_of to make this work
+#[test]
+fn test_type_of_for_num() {
+    let (analysis, range) = single_file_with_range(
+        r#"
+        fn main() {
+            let foo_test = <|>"foo"<|>;
+        }
+        "#,
+    );
+    assert!(analysis.type_of(range).unwrap().is_none());
+}
+// FIXME: improve type_of to make this work
+#[test]
+fn test_type_of_for_binding() {
+    let (analysis, range) = single_file_with_range(
+        "
+        pub fn foo() -> u32 { 1 };
+        fn main() {
+            let <|>foo_test<|> = foo();
+        }
+        ",
+    );
+    assert!(analysis.type_of(range).unwrap().is_none());
+}
+// FIXME: improve type_of to make this work
+#[test]
+fn test_type_of_for_expr_1() {
+    let (analysis, range) = single_file_with_range(
+        "
+        fn main() {
+            let foo = <|>1 + foo_test<|>;
+        }
+        ",
+    );
+    let type_name = analysis.type_of(range).unwrap().unwrap();
+    assert_eq!("[unknown]", &type_name);
+}
+// FIXME: improve type_of to make this work
+#[test]
+fn test_type_of_for_expr_2() {
+    let (analysis, range) = single_file_with_range(
+        "
+        fn main() {
+            let foo: usize = 1;
+            let bar = <|>1 + foo_test<|>;
+        }
+        ",
+    );
+    let type_name = analysis.type_of(range).unwrap().unwrap();
+    assert_eq!("[unknown]", &type_name);
+}
diff --git a/crates/ra_cli/src/main.rs b/crates/ra_cli/src/main.rs
index 939f7fe77..a3b856aa9 100644
--- a/crates/ra_cli/src/main.rs
+++ b/crates/ra_cli/src/main.rs
@@ -102,7 +102,7 @@ fn selections(file: &SourceFileNode, start: u32, end: u32) -> String {
    let mut cur = Some(TextRange::from_to((start - 1).into(), (end - 1).into()));
    while let Some(r) = cur {
        ranges.push(r);
-        cur = extend_selection(&file, r);
+        cur = extend_selection(file.syntax(), r);
    }
    let ranges = ranges
        .iter()
diff --git a/crates/ra_db/src/syntax_ptr.rs b/crates/ra_db/src/syntax_ptr.rs
index dac94dd36..744cb2352 100644
--- a/crates/ra_db/src/syntax_ptr.rs
+++ b/crates/ra_db/src/syntax_ptr.rs
@@ -31,6 +31,10 @@ impl LocalSyntaxPtr {
    pub fn range(self) -> TextRange {
        self.range
    }
+    pub fn kind(self) -> SyntaxKind {
+        self.kind
+    }
 }
 #[test]
diff --git a/crates/ra_editor/src/assists.rs b/crates/ra_editor/src/assists.rs
new file mode 100644
index 000000000..cc40ee4c8
--- /dev/null
+++ b/crates/ra_editor/src/assists.rs
@@ -0,0 +1,185 @@
+//! This modules contains various "assits": suggestions for source code edits
+//! which are likely to occur at a given cursor positon. For example, if the
+//! cursor is on the `,`, a possible assist is swapping the elments around the
+//! comma.
+mod flip_comma;
+mod add_derive;
+mod add_impl;
+mod introduce_variable;
+mod change_visibility;
+use ra_text_edit::{TextEdit, TextEditBuilder};
+use ra_syntax::{
+    Direction, SyntaxNodeRef, TextUnit, TextRange,SourceFileNode, AstNode,
+    algo::{find_leaf_at_offset, find_covering_node, LeafAtOffset},
+};
+use crate::find_node_at_offset;
+pub use self::{
+    flip_comma::flip_comma,
+    add_derive::add_derive,
+    add_impl::add_impl,
+    introduce_variable::introduce_variable,
+    change_visibility::change_visibility,
+};
+/// Return all the assists applicable at the given position.
+pub fn assists(file: &SourceFileNode, range: TextRange) -> Vec<LocalEdit> {
+    let ctx = AssistCtx::new(file, range);
+    [
+        flip_comma,
+        add_derive,
+        add_impl,
+        introduce_variable,
+        change_visibility,
+    ]
+    .iter()
+    .filter_map(|&assist| ctx.clone().apply(assist))
+    .collect()
+}
+#[derive(Debug)]
+pub struct LocalEdit {
+    pub label: String,
+    pub edit: TextEdit,
+    pub cursor_position: Option<TextUnit>,
+}
+fn non_trivia_sibling(node: SyntaxNodeRef, direction: Direction) -> Option<SyntaxNodeRef> {
+    node.siblings(direction)
+        .skip(1)
+        .find(|node| !node.kind().is_trivia())
+}
+/// `AssistCtx` allows to apply an assist or check if it could be applied.
+///
+/// Assists use a somewhat overengeneered approach, given the current needs. The
+/// assists workflow consists of two phases. In the first phase, a user asks for
+/// the list of available assists. In the second phase, the user picks a
+/// particular assist and it gets applied.
+///
+/// There are two peculiarities here:
+///
+/// * first, we ideally avoid computing more things then neccessary to answer
+///   "is assist applicable" in the first phase.
+/// * second, when we are appling assist, we don't have a gurantee that there
+///   weren't any changes between the point when user asked for assists and when
+///   they applied a particular assist. So, when applying assist, we need to do
+///   all the checks from scratch.
+///
+/// To avoid repeating the same code twice for both "check" and "apply"
+/// functions, we use an approach remeniscent of that of Django's function based
+/// views dealing with forms. Each assist receives a runtime parameter,
+/// `should_compute_edit`. It first check if an edit is applicable (potentially
+/// computing info required to compute the actual edit). If it is applicable,
+/// and `should_compute_edit` is `true`, it then computes the actual edit.
+///
+/// So, to implement the original assists workflow, we can first apply each edit
+/// with `should_compute_edit = false`, and then applying the selected edit
+/// again, with `should_compute_edit = true` this time.
+///
+/// Note, however, that we don't actually use such two-phase logic at the
+/// moment, because the LSP API is pretty awkward in this place, and it's much
+/// easier to just compute the edit eagarly :-)
+#[derive(Debug, Clone)]
+pub struct AssistCtx<'a> {
+    source_file: &'a SourceFileNode,
+    range: TextRange,
+    should_compute_edit: bool,
+}
+#[derive(Debug)]
+pub enum Assist {
+    Applicable,
+    Edit(LocalEdit),
+}
+#[derive(Default)]
+struct AssistBuilder {
+    edit: TextEditBuilder,
+    cursor_position: Option<TextUnit>,
+}
+impl<'a> AssistCtx<'a> {
+    pub fn new(source_file: &'a SourceFileNode, range: TextRange) -> AssistCtx {
+        AssistCtx {
+            source_file,
+            range,
+            should_compute_edit: false,
+        }
+    }
+    pub fn apply(mut self, assist: fn(AssistCtx) -> Option<Assist>) -> Option<LocalEdit> {
+        self.should_compute_edit = true;
+        match assist(self) {
+            None => None,
+            Some(Assist::Edit(e)) => Some(e),
+            Some(Assist::Applicable) => unreachable!(),
+        }
+    }
+    pub fn check(mut self, assist: fn(AssistCtx) -> Option<Assist>) -> bool {
+        self.should_compute_edit = false;
+        match assist(self) {
+            None => false,
+            Some(Assist::Edit(_)) => unreachable!(),
+            Some(Assist::Applicable) => true,
+        }
+    }
+    fn build(self, label: impl Into<String>, f: impl FnOnce(&mut AssistBuilder)) -> Option<Assist> {
+        if !self.should_compute_edit {
+            return Some(Assist::Applicable);
+        }
+        let mut edit = AssistBuilder::default();
+        f(&mut edit);
+        Some(Assist::Edit(LocalEdit {
+            label: label.into(),
+            edit: edit.edit.finish(),
+            cursor_position: edit.cursor_position,
+        }))
+    }
+    pub(crate) fn leaf_at_offset(&self) -> LeafAtOffset<SyntaxNodeRef<'a>> {
+        find_leaf_at_offset(self.source_file.syntax(), self.range.start())
+    }
+    pub(crate) fn node_at_offset<N: AstNode<'a>>(&self) -> Option<N> {
+        find_node_at_offset(self.source_file.syntax(), self.range.start())
+    }
+    pub(crate) fn covering_node(&self) -> SyntaxNodeRef<'a> {
+        find_covering_node(self.source_file.syntax(), self.range)
+    }
+}
+impl AssistBuilder {
+    fn replace(&mut self, range: TextRange, replace_with: impl Into<String>) {
+        self.edit.replace(range, replace_with.into())
+    }
+    #[allow(unused)]
+    fn delete(&mut self, range: TextRange) {
+        self.edit.delete(range)
+    }
+    fn insert(&mut self, offset: TextUnit, text: impl Into<String>) {
+        self.edit.insert(offset, text.into())
+    }
+    fn set_cursor(&mut self, offset: TextUnit) {
+        self.cursor_position = Some(offset)
+    }
+}
+#[cfg(test)]
+fn check_assist(assist: fn(AssistCtx) -> Option<Assist>, before: &str, after: &str) {
+    crate::test_utils::check_action(before, after, |file, off| {
+        let range = TextRange::offset_len(off, 0.into());
+        AssistCtx::new(file, range).apply(assist)
+    })
+}
+#[cfg(test)]
+fn check_assist_range(assist: fn(AssistCtx) -> Option<Assist>, before: &str, after: &str) {
+    crate::test_utils::check_action_range(before, after, |file, range| {
+        AssistCtx::new(file, range).apply(assist)
+    })
+}
diff --git a/crates/ra_editor/src/assists/add_derive.rs b/crates/ra_editor/src/assists/add_derive.rs
new file mode 100644
index 000000000..1e2cd4f30
--- /dev/null
+++ b/crates/ra_editor/src/assists/add_derive.rs
@@ -0,0 +1,84 @@
+use ra_syntax::{
+    ast::{self, AstNode, AttrsOwner},
+    SyntaxKind::{WHITESPACE, COMMENT},
+    TextUnit,
+};
+use crate::assists::{AssistCtx, Assist};
+pub fn add_derive(ctx: AssistCtx) -> Option<Assist> {
+    let nominal = ctx.node_at_offset::<ast::NominalDef>()?;
+    let node_start = derive_insertion_offset(nominal)?;
+    ctx.build("add `#[derive]`", |edit| {
+        let derive_attr = nominal
+            .attrs()
+            .filter_map(|x| x.as_call())
+            .filter(|(name, _arg)| name == "derive")
+            .map(|(_name, arg)| arg)
+            .next();
+        let offset = match derive_attr {
+            None => {
+                edit.insert(node_start, "#[derive()]\n");
+                node_start + TextUnit::of_str("#[derive(")
+            }
+            Some(tt) => tt.syntax().range().end() - TextUnit::of_char(')'),
+        };
+        edit.set_cursor(offset)
+    })
+}
+// Insert `derive` after doc comments.
+fn derive_insertion_offset(nominal: ast::NominalDef) -> Option<TextUnit> {
+    let non_ws_child = nominal
+        .syntax()
+        .children()
+        .find(|it| it.kind() != COMMENT && it.kind() != WHITESPACE)?;
+    Some(non_ws_child.range().start())
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::assists::check_assist;
+    #[test]
+    fn add_derive_new() {
+        check_assist(
+            add_derive,
+            "struct Foo { a: i32, <|>}",
+            "#[derive(<|>)]\nstruct Foo { a: i32, }",
+        );
+        check_assist(
+            add_derive,
+            "struct Foo { <|> a: i32, }",
+            "#[derive(<|>)]\nstruct Foo {  a: i32, }",
+        );
+    }
+    #[test]
+    fn add_derive_existing() {
+        check_assist(
+            add_derive,
+            "#[derive(Clone)]\nstruct Foo { a: i32<|>, }",
+            "#[derive(Clone<|>)]\nstruct Foo { a: i32, }",
+        );
+    }
+    #[test]
+    fn add_derive_new_with_doc_comment() {
+        check_assist(
+            add_derive,
+            "
+/// `Foo` is a pretty important struct.
+/// It does stuff.
+struct Foo { a: i32<|>, }
+            ",
+            "
+/// `Foo` is a pretty important struct.
+/// It does stuff.
+#[derive(<|>)]
+struct Foo { a: i32, }
+            ",
+        );
+    }
+}
diff --git a/crates/ra_editor/src/assists/add_impl.rs b/crates/ra_editor/src/assists/add_impl.rs
new file mode 100644
index 000000000..9353e2717
--- /dev/null
+++ b/crates/ra_editor/src/assists/add_impl.rs
@@ -0,0 +1,66 @@
+use join_to_string::join;
+use ra_syntax::{
+    ast::{self, AstNode, NameOwner, TypeParamsOwner},
+    TextUnit,
+};
+use crate::assists::{AssistCtx, Assist};
+pub fn add_impl(ctx: AssistCtx) -> Option<Assist> {
+    let nominal = ctx.node_at_offset::<ast::NominalDef>()?;
+    let name = nominal.name()?;
+    ctx.build("add impl", |edit| {
+        let type_params = nominal.type_param_list();
+        let start_offset = nominal.syntax().range().end();
+        let mut buf = String::new();
+        buf.push_str("\n\nimpl");
+        if let Some(type_params) = type_params {
+            type_params.syntax().text().push_to(&mut buf);
+        }
+        buf.push_str(" ");
+        buf.push_str(name.text().as_str());
+        if let Some(type_params) = type_params {
+            let lifetime_params = type_params
+                .lifetime_params()
+                .filter_map(|it| it.lifetime())
+                .map(|it| it.text());
+            let type_params = type_params
+                .type_params()
+                .filter_map(|it| it.name())
+                .map(|it| it.text());
+            join(lifetime_params.chain(type_params))
+                .surround_with("<", ">")
+                .to_buf(&mut buf);
+        }
+        buf.push_str(" {\n");
+        edit.set_cursor(start_offset + TextUnit::of_str(&buf));
+        buf.push_str("\n}");
+        edit.insert(start_offset, buf);
+    })
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::assists::check_assist;
+    #[test]
+    fn test_add_impl() {
+        check_assist(
+            add_impl,
+            "struct Foo {<|>}\n",
+            "struct Foo {}\n\nimpl Foo {\n<|>\n}\n",
+        );
+        check_assist(
+            add_impl,
+            "struct Foo<T: Clone> {<|>}",
+            "struct Foo<T: Clone> {}\n\nimpl<T: Clone> Foo<T> {\n<|>\n}",
+        );
+        check_assist(
+            add_impl,
+            "struct Foo<'a, T: Foo<'a>> {<|>}",
+            "struct Foo<'a, T: Foo<'a>> {}\n\nimpl<'a, T: Foo<'a>> Foo<'a, T> {\n<|>\n}",
+        );
+    }
+}
diff --git a/crates/ra_editor/src/assists/change_visibility.rs b/crates/ra_editor/src/assists/change_visibility.rs
new file mode 100644
index 000000000..ac75f635e
--- /dev/null
+++ b/crates/ra_editor/src/assists/change_visibility.rs
@@ -0,0 +1,88 @@
+use ra_syntax::{
+    AstNode,
+    ast::{self, VisibilityOwner, NameOwner},
+    SyntaxKind::{VISIBILITY, FN_KW, MOD_KW, STRUCT_KW, ENUM_KW, TRAIT_KW, FN_DEF, MODULE, STRUCT_DEF, ENUM_DEF, TRAIT_DEF, IDENT},
+};
+use crate::assists::{AssistCtx, Assist};
+pub fn change_visibility(ctx: AssistCtx) -> Option<Assist> {
+    let offset = if let Some(keyword) = ctx.leaf_at_offset().find(|leaf| match leaf.kind() {
+        FN_KW | MOD_KW | STRUCT_KW | ENUM_KW | TRAIT_KW => true,
+        _ => false,
+    }) {
+        let parent = keyword.parent()?;
+        let def_kws = vec![FN_DEF, MODULE, STRUCT_DEF, ENUM_DEF, TRAIT_DEF];
+        // Parent is not a definition, can't add visibility
+        if !def_kws.iter().any(|&def_kw| def_kw == parent.kind()) {
+            return None;
+        }
+        // Already have visibility, do nothing
+        if parent.children().any(|child| child.kind() == VISIBILITY) {
+            return None;
+        }
+        parent.range().start()
+    } else {
+        let ident = ctx.leaf_at_offset().find(|leaf| leaf.kind() == IDENT)?;
+        let field = ident.ancestors().find_map(ast::NamedFieldDef::cast)?;
+        if field.name()?.syntax().range() != ident.range() && field.visibility().is_some() {
+            return None;
+        }
+        field.syntax().range().start()
+    };
+    ctx.build("make pub(crate)", |edit| {
+        edit.insert(offset, "pub(crate) ");
+        edit.set_cursor(offset);
+    })
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::assists::check_assist;
+    #[test]
+    fn change_visibility_adds_pub_crate_to_items() {
+        check_assist(
+            change_visibility,
+            "<|>fn foo() {}",
+            "<|>pub(crate) fn foo() {}",
+        );
+        check_assist(
+            change_visibility,
+            "f<|>n foo() {}",
+            "<|>pub(crate) fn foo() {}",
+        );
+        check_assist(
+            change_visibility,
+            "<|>struct Foo {}",
+            "<|>pub(crate) struct Foo {}",
+        );
+        check_assist(
+            change_visibility,
+            "<|>mod foo {}",
+            "<|>pub(crate) mod foo {}",
+        );
+        check_assist(
+            change_visibility,
+            "<|>trait Foo {}",
+            "<|>pub(crate) trait Foo {}",
+        );
+        check_assist(change_visibility, "m<|>od {}", "<|>pub(crate) mod {}");
+        check_assist(
+            change_visibility,
+            "unsafe f<|>n foo() {}",
+            "<|>pub(crate) unsafe fn foo() {}",
+        );
+    }
+    #[test]
+    fn change_visibility_works_with_struct_fields() {
+        check_assist(
+            change_visibility,
+            "struct S { <|>field: u32 }",
+            "struct S { <|>pub(crate) field: u32 }",
+        )
+    }
+}
diff --git a/crates/ra_editor/src/assists/flip_comma.rs b/crates/ra_editor/src/assists/flip_comma.rs
new file mode 100644
index 000000000..a343413cc
--- /dev/null
+++ b/crates/ra_editor/src/assists/flip_comma.rs
@@ -0,0 +1,31 @@
+use ra_syntax::{
+    Direction,
+    SyntaxKind::COMMA,
+};
+use crate::assists::{non_trivia_sibling, AssistCtx, Assist};
+pub fn flip_comma(ctx: AssistCtx) -> Option<Assist> {
+    let comma = ctx.leaf_at_offset().find(|leaf| leaf.kind() == COMMA)?;
+    let prev = non_trivia_sibling(comma, Direction::Prev)?;
+    let next = non_trivia_sibling(comma, Direction::Next)?;
+    ctx.build("flip comma", |edit| {
+        edit.replace(prev.range(), next.text());
+        edit.replace(next.range(), prev.text());
+    })
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::assists::check_assist;
+    #[test]
+    fn flip_comma_works_for_function_parameters() {
+        check_assist(
+            flip_comma,
+            "fn foo(x: i32,<|> y: Result<(), ()>) {}",
+            "fn foo(y: Result<(), ()>,<|> x: i32) {}",
+        )
+    }
+}
diff --git a/crates/ra_editor/src/assists/introduce_variable.rs b/crates/ra_editor/src/assists/introduce_variable.rs
new file mode 100644
index 000000000..782861023
--- /dev/null
+++ b/crates/ra_editor/src/assists/introduce_variable.rs
@@ -0,0 +1,144 @@
+use ra_syntax::{
+    ast::{self, AstNode},
+    SyntaxKind::WHITESPACE,
+    SyntaxNodeRef, TextUnit,
+};
+use crate::assists::{AssistCtx, Assist};
+pub fn introduce_variable<'a>(ctx: AssistCtx) -> Option<Assist> {
+    let node = ctx.covering_node();
+    let expr = node.ancestors().filter_map(ast::Expr::cast).next()?;
+    let anchor_stmt = anchor_stmt(expr)?;
+    let indent = anchor_stmt.prev_sibling()?;
+    if indent.kind() != WHITESPACE {
+        return None;
+    }
+    ctx.build("introduce variable", move |edit| {
+        let mut buf = String::new();
+        buf.push_str("let var_name = ");
+        expr.syntax().text().push_to(&mut buf);
+        let is_full_stmt = if let Some(expr_stmt) = ast::ExprStmt::cast(anchor_stmt) {
+            Some(expr.syntax()) == expr_stmt.expr().map(|e| e.syntax())
+        } else {
+            false
+        };
+        if is_full_stmt {
+            edit.replace(expr.syntax().range(), buf);
+        } else {
+            buf.push_str(";");
+            indent.text().push_to(&mut buf);
+            edit.replace(expr.syntax().range(), "var_name".to_string());
+            edit.insert(anchor_stmt.range().start(), buf);
+        }
+        edit.set_cursor(anchor_stmt.range().start() + TextUnit::of_str("let "));
+    })
+}
+/// Statement or last in the block expression, which will follow
+/// the freshly introduced var.
+fn anchor_stmt(expr: ast::Expr) -> Option<SyntaxNodeRef> {
+    expr.syntax().ancestors().find(|&node| {
+        if ast::Stmt::cast(node).is_some() {
+            return true;
+        }
+        if let Some(expr) = node
+            .parent()
+            .and_then(ast::Block::cast)
+            .and_then(|it| it.expr())
+        {
+            if expr.syntax() == node {
+                return true;
+            }
+        }
+        false
+    })
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::assists::check_assist_range;
+    #[test]
+    fn test_introduce_var_simple() {
+        check_assist_range(
+            introduce_variable,
+            "
+fn foo() {
+    foo(<|>1 + 1<|>);
+}",
+            "
+fn foo() {
+    let <|>var_name = 1 + 1;
+    foo(var_name);
+}",
+        );
+    }
+    #[test]
+    fn test_introduce_var_expr_stmt() {
+        check_assist_range(
+            introduce_variable,
+            "
+fn foo() {
+    <|>1 + 1<|>;
+}",
+            "
+fn foo() {
+    let <|>var_name = 1 + 1;
+}",
+        );
+    }
+    #[test]
+    fn test_introduce_var_part_of_expr_stmt() {
+        check_assist_range(
+            introduce_variable,
+            "
+fn foo() {
+    <|>1<|> + 1;
+}",
+            "
+fn foo() {
+    let <|>var_name = 1;
+    var_name + 1;
+}",
+        );
+    }
+    #[test]
+    fn test_introduce_var_last_expr() {
+        check_assist_range(
+            introduce_variable,
+            "
+fn foo() {
+    bar(<|>1 + 1<|>)
+}",
+            "
+fn foo() {
+    let <|>var_name = 1 + 1;
+    bar(var_name)
+}",
+        );
+    }
+    #[test]
+    fn test_introduce_var_last_full_expr() {
+        check_assist_range(
+            introduce_variable,
+            "
+fn foo() {
+    <|>bar(1 + 1)<|>
+}",
+            "
+fn foo() {
+    let <|>var_name = bar(1 + 1);
+    var_name
+}",
+        );
+    }
+}
diff --git a/crates/ra_editor/src/code_actions.rs b/crates/ra_editor/src/code_actions.rs
deleted file mode 100644
index 7615f37a6..000000000
--- a/crates/ra_editor/src/code_actions.rs
+++ /dev/null
@@ -1,415 +0,0 @@
-use join_to_string::join;
-use ra_syntax::{
-    algo::{find_covering_node, find_leaf_at_offset},
-    ast::{self, AstNode, AttrsOwner, NameOwner, TypeParamsOwner},
-    Direction, SourceFileNode,
-    SyntaxKind::{COMMA, WHITESPACE, COMMENT, VISIBILITY, FN_KW, MOD_KW, STRUCT_KW, ENUM_KW, TRAIT_KW, FN_DEF, MODULE, STRUCT_DEF, ENUM_DEF, TRAIT_DEF},
-    SyntaxNodeRef, TextRange, TextUnit,
-};
-use crate::{find_node_at_offset, TextEdit, TextEditBuilder};
-#[derive(Debug)]
-pub struct LocalEdit {
-    pub label: String,
-    pub edit: TextEdit,
-    pub cursor_position: Option<TextUnit>,
-}
-pub fn flip_comma<'a>(
-    file: &'a SourceFileNode,
-    offset: TextUnit,
-) -> Option<impl FnOnce() -> LocalEdit + 'a> {
-    let syntax = file.syntax();
-    let comma = find_leaf_at_offset(syntax, offset).find(|leaf| leaf.kind() == COMMA)?;
-    let prev = non_trivia_sibling(comma, Direction::Prev)?;
-    let next = non_trivia_sibling(comma, Direction::Next)?;
-    Some(move || {
-        let mut edit = TextEditBuilder::new();
-        edit.replace(prev.range(), next.text().to_string());
-        edit.replace(next.range(), prev.text().to_string());
-        LocalEdit {
-            label: "flip comma".to_string(),
-            edit: edit.finish(),
-            cursor_position: None,
-        }
-    })
-}
-pub fn add_derive<'a>(
-    file: &'a SourceFileNode,
-    offset: TextUnit,
-) -> Option<impl FnOnce() -> LocalEdit + 'a> {
-    let nominal = find_node_at_offset::<ast::NominalDef>(file.syntax(), offset)?;
-    let node_start = derive_insertion_offset(nominal)?;
-    return Some(move || {
-        let derive_attr = nominal
-            .attrs()
-            .filter_map(|x| x.as_call())
-            .filter(|(name, _arg)| name == "derive")
-            .map(|(_name, arg)| arg)
-            .next();
-        let mut edit = TextEditBuilder::new();
-        let offset = match derive_attr {
-            None => {
-                edit.insert(node_start, "#[derive()]\n".to_string());
-                node_start + TextUnit::of_str("#[derive(")
-            }
-            Some(tt) => tt.syntax().range().end() - TextUnit::of_char(')'),
-        };
-        LocalEdit {
-            label: "add `#[derive]`".to_string(),
-            edit: edit.finish(),
-            cursor_position: Some(offset),
-        }
-    });
-    // Insert `derive` after doc comments.
-    fn derive_insertion_offset(nominal: ast::NominalDef) -> Option<TextUnit> {
-        let non_ws_child = nominal
-            .syntax()
-            .children()
-            .find(|it| it.kind() != COMMENT && it.kind() != WHITESPACE)?;
-        Some(non_ws_child.range().start())
-    }
-}
-pub fn add_impl<'a>(
-    file: &'a SourceFileNode,
-    offset: TextUnit,
-) -> Option<impl FnOnce() -> LocalEdit + 'a> {
-    let nominal = find_node_at_offset::<ast::NominalDef>(file.syntax(), offset)?;
-    let name = nominal.name()?;
-    Some(move || {
-        let type_params = nominal.type_param_list();
-        let mut edit = TextEditBuilder::new();
-        let start_offset = nominal.syntax().range().end();
-        let mut buf = String::new();
-        buf.push_str("\n\nimpl");
-        if let Some(type_params) = type_params {
-            type_params.syntax().text().push_to(&mut buf);
-        }
-        buf.push_str(" ");
-        buf.push_str(name.text().as_str());
-        if let Some(type_params) = type_params {
-            let lifetime_params = type_params
-                .lifetime_params()
-                .filter_map(|it| it.lifetime())
-                .map(|it| it.text());
-            let type_params = type_params
-                .type_params()
-                .filter_map(|it| it.name())
-                .map(|it| it.text());
-            join(lifetime_params.chain(type_params))
-                .surround_with("<", ">")
-                .to_buf(&mut buf);
-        }
-        buf.push_str(" {\n");
-        let offset = start_offset + TextUnit::of_str(&buf);
-        buf.push_str("\n}");
-        edit.insert(start_offset, buf);
-        LocalEdit {
-            label: "add impl".to_string(),
-            edit: edit.finish(),
-            cursor_position: Some(offset),
-        }
-    })
-}
-pub fn introduce_variable<'a>(
-    file: &'a SourceFileNode,
-    range: TextRange,
-) -> Option<impl FnOnce() -> LocalEdit + 'a> {
-    let node = find_covering_node(file.syntax(), range);
-    let expr = node.ancestors().filter_map(ast::Expr::cast).next()?;
-    let anchor_stmt = anchor_stmt(expr)?;
-    let indent = anchor_stmt.prev_sibling()?;
-    if indent.kind() != WHITESPACE {
-        return None;
-    }
-    return Some(move || {
-        let mut buf = String::new();
-        let mut edit = TextEditBuilder::new();
-        buf.push_str("let var_name = ");
-        expr.syntax().text().push_to(&mut buf);
-        let is_full_stmt = if let Some(expr_stmt) = ast::ExprStmt::cast(anchor_stmt) {
-            Some(expr.syntax()) == expr_stmt.expr().map(|e| e.syntax())
-        } else {
-            false
-        };
-        if is_full_stmt {
-            edit.replace(expr.syntax().range(), buf);
-        } else {
-            buf.push_str(";");
-            indent.text().push_to(&mut buf);
-            edit.replace(expr.syntax().range(), "var_name".to_string());
-            edit.insert(anchor_stmt.range().start(), buf);
-        }
-        let cursor_position = anchor_stmt.range().start() + TextUnit::of_str("let ");
-        LocalEdit {
-            label: "introduce variable".to_string(),
-            edit: edit.finish(),
-            cursor_position: Some(cursor_position),
-        }
-    });
-    /// Statement or last in the block expression, which will follow
-    /// the freshly introduced var.
-    fn anchor_stmt(expr: ast::Expr) -> Option<SyntaxNodeRef> {
-        expr.syntax().ancestors().find(|&node| {
-            if ast::Stmt::cast(node).is_some() {
-                return true;
-            }
-            if let Some(expr) = node
-                .parent()
-                .and_then(ast::Block::cast)
-                .and_then(|it| it.expr())
-            {
-                if expr.syntax() == node {
-                    return true;
-                }
-            }
-            false
-        })
-    }
-}
-pub fn make_pub_crate<'a>(
-    file: &'a SourceFileNode,
-    offset: TextUnit,
-) -> Option<impl FnOnce() -> LocalEdit + 'a> {
-    let syntax = file.syntax();
-    let keyword = find_leaf_at_offset(syntax, offset).find(|leaf| match leaf.kind() {
-        FN_KW | MOD_KW | STRUCT_KW | ENUM_KW | TRAIT_KW => true,
-        _ => false,
-    })?;
-    let parent = keyword.parent()?;
-    let def_kws = vec![FN_DEF, MODULE, STRUCT_DEF, ENUM_DEF, TRAIT_DEF];
-    let node_start = parent.range().start();
-    Some(move || {
-        let mut edit = TextEditBuilder::new();
-        if !def_kws.iter().any(|&def_kw| def_kw == parent.kind())
-            || parent.children().any(|child| child.kind() == VISIBILITY)
-        {
-            return LocalEdit {
-                label: "make pub crate".to_string(),
-                edit: edit.finish(),
-                cursor_position: Some(offset),
-            };
-        }
-        edit.insert(node_start, "pub(crate) ".to_string());
-        LocalEdit {
-            label: "make pub crate".to_string(),
-            edit: edit.finish(),
-            cursor_position: Some(node_start),
-        }
-    })
-}
-fn non_trivia_sibling(node: SyntaxNodeRef, direction: Direction) -> Option<SyntaxNodeRef> {
-    node.siblings(direction)
-        .skip(1)
-        .find(|node| !node.kind().is_trivia())
-}
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::test_utils::{check_action, check_action_range};
-    #[test]
-    fn test_swap_comma() {
-        check_action(
-            "fn foo(x: i32,<|> y: Result<(), ()>) {}",
-            "fn foo(y: Result<(), ()>,<|> x: i32) {}",
-            |file, off| flip_comma(file, off).map(|f| f()),
-        )
-    }
-    #[test]
-    fn add_derive_new() {
-        check_action(
-            "struct Foo { a: i32, <|>}",
-            "#[derive(<|>)]\nstruct Foo { a: i32, }",
-            |file, off| add_derive(file, off).map(|f| f()),
-        );
-        check_action(
-            "struct Foo { <|> a: i32, }",
-            "#[derive(<|>)]\nstruct Foo {  a: i32, }",
-            |file, off| add_derive(file, off).map(|f| f()),
-        );
-    }
-    #[test]
-    fn add_derive_existing() {
-        check_action(
-            "#[derive(Clone)]\nstruct Foo { a: i32<|>, }",
-            "#[derive(Clone<|>)]\nstruct Foo { a: i32, }",
-            |file, off| add_derive(file, off).map(|f| f()),
-        );
-    }
-    #[test]
-    fn add_derive_new_with_doc_comment() {
-        check_action(
-            "
-/// `Foo` is a pretty important struct.
-/// It does stuff.
-struct Foo { a: i32<|>, }
-            ",
-            "
-/// `Foo` is a pretty important struct.
-/// It does stuff.
-#[derive(<|>)]
-struct Foo { a: i32, }
-            ",
-            |file, off| add_derive(file, off).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_add_impl() {
-        check_action(
-            "struct Foo {<|>}\n",
-            "struct Foo {}\n\nimpl Foo {\n<|>\n}\n",
-            |file, off| add_impl(file, off).map(|f| f()),
-        );
-        check_action(
-            "struct Foo<T: Clone> {<|>}",
-            "struct Foo<T: Clone> {}\n\nimpl<T: Clone> Foo<T> {\n<|>\n}",
-            |file, off| add_impl(file, off).map(|f| f()),
-        );
-        check_action(
-            "struct Foo<'a, T: Foo<'a>> {<|>}",
-            "struct Foo<'a, T: Foo<'a>> {}\n\nimpl<'a, T: Foo<'a>> Foo<'a, T> {\n<|>\n}",
-            |file, off| add_impl(file, off).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_introduce_var_simple() {
-        check_action_range(
-            "
-fn foo() {
-    foo(<|>1 + 1<|>);
-}",
-            "
-fn foo() {
-    let <|>var_name = 1 + 1;
-    foo(var_name);
-}",
-            |file, range| introduce_variable(file, range).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_introduce_var_expr_stmt() {
-        check_action_range(
-            "
-fn foo() {
-    <|>1 + 1<|>;
-}",
-            "
-fn foo() {
-    let <|>var_name = 1 + 1;
-}",
-            |file, range| introduce_variable(file, range).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_introduce_var_part_of_expr_stmt() {
-        check_action_range(
-            "
-fn foo() {
-    <|>1<|> + 1;
-}",
-            "
-fn foo() {
-    let <|>var_name = 1;
-    var_name + 1;
-}",
-            |file, range| introduce_variable(file, range).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_introduce_var_last_expr() {
-        check_action_range(
-            "
-fn foo() {
-    bar(<|>1 + 1<|>)
-}",
-            "
-fn foo() {
-    let <|>var_name = 1 + 1;
-    bar(var_name)
-}",
-            |file, range| introduce_variable(file, range).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_introduce_var_last_full_expr() {
-        check_action_range(
-            "
-fn foo() {
-    <|>bar(1 + 1)<|>
-}",
-            "
-fn foo() {
-    let <|>var_name = bar(1 + 1);
-    var_name
-}",
-            |file, range| introduce_variable(file, range).map(|f| f()),
-        );
-    }
-    #[test]
-    fn test_make_pub_crate() {
-        check_action(
-            "<|>fn foo() {}",
-            "<|>pub(crate) fn foo() {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-        check_action(
-            "f<|>n foo() {}",
-            "<|>pub(crate) fn foo() {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-        check_action(
-            "<|>struct Foo {}",
-            "<|>pub(crate) struct Foo {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-        check_action("<|>mod foo {}", "<|>pub(crate) mod foo {}", |file, off| {
-            make_pub_crate(file, off).map(|f| f())
-        });
-        check_action(
-            "<|>trait Foo {}",
-            "<|>pub(crate) trait Foo {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-        check_action("m<|>od {}", "<|>pub(crate) mod {}", |file, off| {
-            make_pub_crate(file, off).map(|f| f())
-        });
-        check_action(
-            "pub(crate) f<|>n foo() {}",
-            "pub(crate) f<|>n foo() {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-        check_action(
-            "unsafe f<|>n foo() {}",
-            "<|>pub(crate) unsafe fn foo() {}",
-            |file, off| make_pub_crate(file, off).map(|f| f()),
-        );
-    }
-}
diff --git a/crates/ra_editor/src/diagnostics.rs b/crates/ra_editor/src/diagnostics.rs
index 1b336cfe2..199b0e502 100644
--- a/crates/ra_editor/src/diagnostics.rs
+++ b/crates/ra_editor/src/diagnostics.rs
@@ -57,7 +57,7 @@ fn check_unnecessary_braces_in_use_statement(
            text_edit_for_remove_unnecessary_braces_with_self_in_use_statement(single_use_tree)
                .unwrap_or_else(|| {
                    let to_replace = single_use_tree.syntax().text().to_string();
-                    let mut edit_builder = TextEditBuilder::new();
+                    let mut edit_builder = TextEditBuilder::default();
                    edit_builder.delete(range);
                    edit_builder.insert(range.start(), to_replace);
                    edit_builder.finish()
@@ -93,7 +93,7 @@ fn text_edit_for_remove_unnecessary_braces_with_self_in_use_statement(
        let start = use_tree_list_node.prev_sibling()?.range().start();
        let end = use_tree_list_node.range().end();
        let range = TextRange::from_to(start, end);
-        let mut edit_builder = TextEditBuilder::new();
+        let mut edit_builder = TextEditBuilder::default();
        edit_builder.delete(range);
        return Some(edit_builder.finish());
    }
@@ -111,7 +111,7 @@ fn check_struct_shorthand_initialization(
            let field_name = name_ref.syntax().text().to_string();
            let field_expr = expr.syntax().text().to_string();
            if field_name == field_expr {
-                let mut edit_builder = TextEditBuilder::new();
+                let mut edit_builder = TextEditBuilder::default();
                edit_builder.delete(named_field.syntax().range());
                edit_builder.insert(named_field.syntax().range().start(), field_name);
                let edit = edit_builder.finish();
diff --git a/crates/ra_editor/src/extend_selection.rs b/crates/ra_editor/src/extend_selection.rs
index 4665a336a..7a423852b 100644
--- a/crates/ra_editor/src/extend_selection.rs
+++ b/crates/ra_editor/src/extend_selection.rs
@@ -1,16 +1,12 @@
 use ra_syntax::{
    algo::{find_covering_node, find_leaf_at_offset, LeafAtOffset},
-    Direction, SourceFileNode,
+    Direction,
    SyntaxKind::*,
    SyntaxNodeRef, TextRange, TextUnit,
 };
-pub fn extend_selection(file: &SourceFileNode, range: TextRange) -> Option<TextRange> {
+pub fn extend_selection(root: SyntaxNodeRef, range: TextRange) -> Option<TextRange> {
-    let syntax = file.syntax();
+    let string_kinds = [COMMENT, STRING, RAW_STRING, BYTE_STRING, RAW_BYTE_STRING];
-    extend(syntax.borrowed(), range)
-}
-pub(crate) fn extend(root: SyntaxNodeRef, range: TextRange) -> Option<TextRange> {
    if range.is_empty() {
        let offset = range.start();
        let mut leaves = find_leaf_at_offset(root, offset);
@@ -20,8 +16,8 @@ pub(crate) fn extend(root: SyntaxNodeRef, range: TextRange) -> Option<TextRange>
        let leaf_range = match leaves {
            LeafAtOffset::None => return None,
            LeafAtOffset::Single(l) => {
-                if l.kind() == COMMENT {
+                if string_kinds.contains(&l.kind()) {
-                    extend_single_word_in_comment(l, offset).unwrap_or_else(|| l.range())
+                    extend_single_word_in_comment_or_string(l, offset).unwrap_or_else(|| l.range())
                } else {
                    l.range()
                }
@@ -31,7 +27,7 @@ pub(crate) fn extend(root: SyntaxNodeRef, range: TextRange) -> Option<TextRange>
        return Some(leaf_range);
    };
    let node = find_covering_node(root, range);
-    if node.kind() == COMMENT && range == node.range() {
+    if string_kinds.contains(&node.kind()) && range == node.range() {
        if let Some(range) = extend_comments(node) {
            return Some(range);
        }
@@ -43,7 +39,10 @@ pub(crate) fn extend(root: SyntaxNodeRef, range: TextRange) -> Option<TextRange>
    }
 }
-fn extend_single_word_in_comment(leaf: SyntaxNodeRef, offset: TextUnit) -> Option<TextRange> {
+fn extend_single_word_in_comment_or_string(
+    leaf: SyntaxNodeRef,
+    offset: TextUnit,
+) -> Option<TextRange> {
    let text: &str = leaf.leaf_text()?;
    let cursor_position: u32 = (offset - leaf.range().start()).into();
@@ -126,6 +125,7 @@ fn adj_comments(node: SyntaxNodeRef, dir: Direction) -> SyntaxNodeRef {
 #[cfg(test)]
 mod tests {
    use super::*;
+    use ra_syntax::SourceFileNode;
    use test_utils::extract_offset;
    fn do_check(before: &str, afters: &[&str]) {
@@ -133,7 +133,7 @@ mod tests {
        let file = SourceFileNode::parse(&before);
        let mut range = TextRange::offset_len(cursor, 0.into());
        for &after in afters {
-            range = extend_selection(&file, range).unwrap();
+            range = extend_selection(file.syntax(), range).unwrap();
            let actual = &before[range];
            assert_eq!(after, actual);
        }
@@ -266,4 +266,16 @@ impl S {
            &["hello", "// hello world"],
        );
    }
+    #[test]
+    fn test_extend_selection_string() {
+        do_check(
+            r#"
+fn bar(){}
+" fn f<|>oo() {"
+    "#,
+            &["foo", "\" fn foo() {\""],
+        );
+    }
 }
diff --git a/crates/ra_editor/src/lib.rs b/crates/ra_editor/src/lib.rs
index a65637d52..ac283e2e0 100644
--- a/crates/ra_editor/src/lib.rs
+++ b/crates/ra_editor/src/lib.rs
@@ -1,28 +1,28 @@
-mod code_actions;
+pub mod assists;
 mod extend_selection;
 mod folding_ranges;
 mod line_index;
 mod line_index_utils;
-mod symbols;
+mod structure;
 #[cfg(test)]
 mod test_utils;
 mod typing;
 mod diagnostics;
 pub use self::{
-    code_actions::{add_derive, add_impl, flip_comma, introduce_variable, make_pub_crate, LocalEdit},
+    assists::LocalEdit,
    extend_selection::extend_selection,
    folding_ranges::{folding_ranges, Fold, FoldKind},
    line_index::{LineCol, LineIndex},
    line_index_utils::translate_offset_with_edit,
-    symbols::{file_structure, file_symbols, FileSymbol, StructureNode},
+    structure::{file_structure, StructureNode},
    typing::{join_lines, on_enter, on_eq_typed},
    diagnostics::diagnostics
 };
-use ra_text_edit::{TextEdit, TextEditBuilder};
+use ra_text_edit::TextEditBuilder;
 use ra_syntax::{
    algo::find_leaf_at_offset,
-    ast::{self, AstNode, NameOwner},
+    ast::{self, AstNode},
    SourceFileNode,
    SyntaxKind::{self, *},
    SyntaxNodeRef, TextRange, TextUnit, Direction,
@@ -49,18 +49,6 @@ pub struct Diagnostic {
    pub fix: Option<LocalEdit>,
 }
-#[derive(Debug)]
-pub struct Runnable {
-    pub range: TextRange,
-    pub kind: RunnableKind,
-}
-#[derive(Debug)]
-pub enum RunnableKind {
-    Test { name: String },
-    Bin,
-}
 pub fn matching_brace(file: &SourceFileNode, offset: TextUnit) -> Option<TextUnit> {
    const BRACES: &[SyntaxKind] = &[
        L_CURLY, R_CURLY, L_BRACK, R_BRACK, L_PAREN, R_PAREN, L_ANGLE, R_ANGLE,
@@ -79,11 +67,11 @@ pub fn matching_brace(file: &SourceFileNode, offset: TextUnit) -> Option<TextUni
    Some(matching_node.range().start())
 }
-pub fn highlight(file: &SourceFileNode) -> Vec<HighlightedRange> {
+pub fn highlight(root: SyntaxNodeRef) -> Vec<HighlightedRange> {
    // Visited nodes to handle highlighting priorities
    let mut highlighted = FxHashSet::default();
    let mut res = Vec::new();
-    for node in file.syntax().descendants() {
+    for node in root.descendants() {
        if highlighted.contains(&node) {
            continue;
        }
@@ -133,29 +121,6 @@ pub fn syntax_tree(file: &SourceFileNode) -> String {
    ::ra_syntax::utils::dump_tree(file.syntax())
 }
-pub fn runnables(file: &SourceFileNode) -> Vec<Runnable> {
-    file.syntax()
-        .descendants()
-        .filter_map(ast::FnDef::cast)
-        .filter_map(|f| {
-            let name = f.name()?.text();
-            let kind = if name == "main" {
-                RunnableKind::Bin
-            } else if f.has_atom_attr("test") {
-                RunnableKind::Test {
-                    name: name.to_string(),
-                }
-            } else {
-                return None;
-            };
-            Some(Runnable {
-                range: f.syntax().range(),
-                kind,
-            })
-        })
-        .collect()
-}
 pub fn find_node_at_offset<'a, N: AstNode<'a>>(
    syntax: SyntaxNodeRef<'a>,
    offset: TextUnit,
@@ -178,7 +143,7 @@ fn main() {}
    println!("Hello, {}!", 92);
 "#,
        );
-        let hls = highlight(&file);
+        let hls = highlight(file.syntax());
        assert_eq_dbg(
            r#"[HighlightedRange { range: [1; 11), tag: "comment" },
                HighlightedRange { range: [12; 14), tag: "keyword" },
@@ -191,29 +156,6 @@ fn main() {}
    }
    #[test]
-    fn test_runnables() {
-        let file = SourceFileNode::parse(
-            r#"
-fn main() {}
-#[test]
-fn test_foo() {}
-#[test]
-#[ignore]
-fn test_foo() {}
-"#,
-        );
-        let runnables = runnables(&file);
-        assert_eq_dbg(
-            r#"[Runnable { range: [1; 13), kind: Bin },
-                Runnable { range: [15; 39), kind: Test { name: "test_foo" } },
-                Runnable { range: [41; 75), kind: Test { name: "test_foo" } }]"#,
-            &runnables,
-        )
-    }
-    #[test]
    fn test_matching_brace() {
        fn do_check(before: &str, after: &str) {
            let (pos, before) = extract_offset(before);
diff --git a/crates/ra_editor/src/structure.rs b/crates/ra_editor/src/structure.rs
new file mode 100644
index 000000000..2292b1ddf
--- /dev/null
+++ b/crates/ra_editor/src/structure.rs
@@ -0,0 +1,129 @@
+use crate::TextRange;
+use ra_syntax::{
+    algo::visit::{visitor, Visitor},
+    ast::{self, NameOwner},
+    AstNode, SourceFileNode, SyntaxKind, SyntaxNodeRef, WalkEvent,
+};
+#[derive(Debug, Clone)]
+pub struct StructureNode {
+    pub parent: Option<usize>,
+    pub label: String,
+    pub navigation_range: TextRange,
+    pub node_range: TextRange,
+    pub kind: SyntaxKind,
+}
+pub fn file_structure(file: &SourceFileNode) -> Vec<StructureNode> {
+    let mut res = Vec::new();
+    let mut stack = Vec::new();
+    for event in file.syntax().preorder() {
+        match event {
+            WalkEvent::Enter(node) => {
+                if let Some(mut symbol) = structure_node(node) {
+                    symbol.parent = stack.last().map(|&n| n);
+                    stack.push(res.len());
+                    res.push(symbol);
+                }
+            }
+            WalkEvent::Leave(node) => {
+                if structure_node(node).is_some() {
+                    stack.pop().unwrap();
+                }
+            }
+        }
+    }
+    res
+}
+fn structure_node(node: SyntaxNodeRef) -> Option<StructureNode> {
+    fn decl<'a, N: NameOwner<'a>>(node: N) -> Option<StructureNode> {
+        let name = node.name()?;
+        Some(StructureNode {
+            parent: None,
+            label: name.text().to_string(),
+            navigation_range: name.syntax().range(),
+            node_range: node.syntax().range(),
+            kind: node.syntax().kind(),
+        })
+    }
+    visitor()
+        .visit(decl::<ast::FnDef>)
+        .visit(decl::<ast::StructDef>)
+        .visit(decl::<ast::NamedFieldDef>)
+        .visit(decl::<ast::EnumDef>)
+        .visit(decl::<ast::TraitDef>)
+        .visit(decl::<ast::Module>)
+        .visit(decl::<ast::TypeDef>)
+        .visit(decl::<ast::ConstDef>)
+        .visit(decl::<ast::StaticDef>)
+        .visit(|im: ast::ImplItem| {
+            let target_type = im.target_type()?;
+            let target_trait = im.target_trait();
+            let label = match target_trait {
+                None => format!("impl {}", target_type.syntax().text()),
+                Some(t) => format!(
+                    "impl {} for {}",
+                    t.syntax().text(),
+                    target_type.syntax().text(),
+                ),
+            };
+            let node = StructureNode {
+                parent: None,
+                label,
+                navigation_range: target_type.syntax().range(),
+                node_range: im.syntax().range(),
+                kind: im.syntax().kind(),
+            };
+            Some(node)
+        })
+        .accept(node)?
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use test_utils::assert_eq_dbg;
+    #[test]
+    fn test_file_structure() {
+        let file = SourceFileNode::parse(
+            r#"
+struct Foo {
+    x: i32
+}
+mod m {
+    fn bar() {}
+}
+enum E { X, Y(i32) }
+type T = ();
+static S: i32 = 92;
+const C: i32 = 92;
+impl E {}
+impl fmt::Debug for E {}
+"#,
+        );
+        let structure = file_structure(&file);
+        assert_eq_dbg(
+            r#"[StructureNode { parent: None, label: "Foo", navigation_range: [8; 11), node_range: [1; 26), kind: STRUCT_DEF },
+                StructureNode { parent: Some(0), label: "x", navigation_range: [18; 19), node_range: [18; 24), kind: NAMED_FIELD_DEF },
+                StructureNode { parent: None, label: "m", navigation_range: [32; 33), node_range: [28; 53), kind: MODULE },
+                StructureNode { parent: Some(2), label: "bar", navigation_range: [43; 46), node_range: [40; 51), kind: FN_DEF },
+                StructureNode { parent: None, label: "E", navigation_range: [60; 61), node_range: [55; 75), kind: ENUM_DEF },
+                StructureNode { parent: None, label: "T", navigation_range: [81; 82), node_range: [76; 88), kind: TYPE_DEF },
+                StructureNode { parent: None, label: "S", navigation_range: [96; 97), node_range: [89; 108), kind: STATIC_DEF },
+                StructureNode { parent: None, label: "C", navigation_range: [115; 116), node_range: [109; 127), kind: CONST_DEF },
+                StructureNode { parent: None, label: "impl E", navigation_range: [134; 135), node_range: [129; 138), kind: IMPL_ITEM },
+                StructureNode { parent: None, label: "impl fmt::Debug for E", navigation_range: [160; 161), node_range: [140; 164), kind: IMPL_ITEM }]"#,
+            &structure,
+        )
+    }
+}
diff --git a/crates/ra_editor/src/symbols.rs b/crates/ra_editor/src/symbols.rs
deleted file mode 100644
index 9e25decfb..000000000
--- a/crates/ra_editor/src/symbols.rs
+++ /dev/null
@@ -1,246 +0,0 @@
-use crate::TextRange;
-use ra_syntax::{
-    algo::visit::{visitor, Visitor},
-    ast::{self, DocCommentsOwner, NameOwner},
-    AstNode, SourceFileNode, SmolStr, SyntaxKind, SyntaxNodeRef, WalkEvent,
-};
-#[derive(Debug, Clone)]
-pub struct StructureNode {
-    pub parent: Option<usize>,
-    pub label: String,
-    pub navigation_range: TextRange,
-    pub node_range: TextRange,
-    pub kind: SyntaxKind,
-}
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct FileSymbol {
-    pub name: SmolStr,
-    pub node_range: TextRange,
-    pub kind: SyntaxKind,
-}
-impl FileSymbol {
-    pub fn docs(&self, file: &SourceFileNode) -> Option<String> {
-        file.syntax()
-            .descendants()
-            .filter(|node| node.kind() == self.kind && node.range() == self.node_range)
-            .filter_map(|node: SyntaxNodeRef| {
-                fn doc_comments<'a, N: DocCommentsOwner<'a>>(node: N) -> Option<String> {
-                    let comments = node.doc_comment_text();
-                    if comments.is_empty() {
-                        None
-                    } else {
-                        Some(comments)
-                    }
-                }
-                visitor()
-                    .visit(doc_comments::<ast::FnDef>)
-                    .visit(doc_comments::<ast::StructDef>)
-                    .visit(doc_comments::<ast::EnumDef>)
-                    .visit(doc_comments::<ast::TraitDef>)
-                    .visit(doc_comments::<ast::Module>)
-                    .visit(doc_comments::<ast::TypeDef>)
-                    .visit(doc_comments::<ast::ConstDef>)
-                    .visit(doc_comments::<ast::StaticDef>)
-                    .accept(node)?
-            })
-            .nth(0)
-    }
-    /// Get a description of this node.
-    ///
-    /// e.g. `struct Name`, `enum Name`, `fn Name`
-    pub fn description(&self, file: &SourceFileNode) -> Option<String> {
-        // TODO: After type inference is done, add type information to improve the output
-        file.syntax()
-            .descendants()
-            .filter(|node| node.kind() == self.kind && node.range() == self.node_range)
-            .filter_map(|node: SyntaxNodeRef| {
-                // TODO: Refactor to be have less repetition
-                visitor()
-                    .visit(|node: ast::FnDef| {
-                        let mut string = "fn ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::StructDef| {
-                        let mut string = "struct ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::EnumDef| {
-                        let mut string = "enum ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::TraitDef| {
-                        let mut string = "trait ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::Module| {
-                        let mut string = "mod ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::TypeDef| {
-                        let mut string = "type ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::ConstDef| {
-                        let mut string = "const ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .visit(|node: ast::StaticDef| {
-                        let mut string = "static ".to_string();
-                        node.name()?.syntax().text().push_to(&mut string);
-                        Some(string)
-                    })
-                    .accept(node)?
-            })
-            .nth(0)
-    }
-}
-pub fn file_symbols(file: &SourceFileNode) -> Vec<FileSymbol> {
-    file.syntax().descendants().filter_map(to_symbol).collect()
-}
-fn to_symbol(node: SyntaxNodeRef) -> Option<FileSymbol> {
-    fn decl<'a, N: NameOwner<'a>>(node: N) -> Option<FileSymbol> {
-        let name = node.name()?;
-        Some(FileSymbol {
-            name: name.text(),
-            node_range: node.syntax().range(),
-            kind: node.syntax().kind(),
-        })
-    }
-    visitor()
-        .visit(decl::<ast::FnDef>)
-        .visit(decl::<ast::StructDef>)
-        .visit(decl::<ast::EnumDef>)
-        .visit(decl::<ast::TraitDef>)
-        .visit(decl::<ast::Module>)
-        .visit(decl::<ast::TypeDef>)
-        .visit(decl::<ast::ConstDef>)
-        .visit(decl::<ast::StaticDef>)
-        .accept(node)?
-}
-pub fn file_structure(file: &SourceFileNode) -> Vec<StructureNode> {
-    let mut res = Vec::new();
-    let mut stack = Vec::new();
-    for event in file.syntax().preorder() {
-        match event {
-            WalkEvent::Enter(node) => {
-                if let Some(mut symbol) = structure_node(node) {
-                    symbol.parent = stack.last().map(|&n| n);
-                    stack.push(res.len());
-                    res.push(symbol);
-                }
-            }
-            WalkEvent::Leave(node) => {
-                if structure_node(node).is_some() {
-                    stack.pop().unwrap();
-                }
-            }
-        }
-    }
-    res
-}
-fn structure_node(node: SyntaxNodeRef) -> Option<StructureNode> {
-    fn decl<'a, N: NameOwner<'a>>(node: N) -> Option<StructureNode> {
-        let name = node.name()?;
-        Some(StructureNode {
-            parent: None,
-            label: name.text().to_string(),
-            navigation_range: name.syntax().range(),
-            node_range: node.syntax().range(),
-            kind: node.syntax().kind(),
-        })
-    }
-    visitor()
-        .visit(decl::<ast::FnDef>)
-        .visit(decl::<ast::StructDef>)
-        .visit(decl::<ast::NamedFieldDef>)
-        .visit(decl::<ast::EnumDef>)
-        .visit(decl::<ast::TraitDef>)
-        .visit(decl::<ast::Module>)
-        .visit(decl::<ast::TypeDef>)
-        .visit(decl::<ast::ConstDef>)
-        .visit(decl::<ast::StaticDef>)
-        .visit(|im: ast::ImplItem| {
-            let target_type = im.target_type()?;
-            let target_trait = im.target_trait();
-            let label = match target_trait {
-                None => format!("impl {}", target_type.syntax().text()),
-                Some(t) => format!(
-                    "impl {} for {}",
-                    t.syntax().text(),
-                    target_type.syntax().text(),
-                ),
-            };
-            let node = StructureNode {
-                parent: None,
-                label,
-                navigation_range: target_type.syntax().range(),
-                node_range: im.syntax().range(),
-                kind: im.syntax().kind(),
-            };
-            Some(node)
-        })
-        .accept(node)?
-}
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use test_utils::assert_eq_dbg;
-    #[test]
-    fn test_file_structure() {
-        let file = SourceFileNode::parse(
-            r#"
-struct Foo {
-    x: i32
-}
-mod m {
-    fn bar() {}
-}
-enum E { X, Y(i32) }
-type T = ();
-static S: i32 = 92;
-const C: i32 = 92;
-impl E {}
-impl fmt::Debug for E {}
-"#,
-        );
-        let symbols = file_structure(&file);
-        assert_eq_dbg(
-            r#"[StructureNode { parent: None, label: "Foo", navigation_range: [8; 11), node_range: [1; 26), kind: STRUCT_DEF },
-                StructureNode { parent: Some(0), label: "x", navigation_range: [18; 19), node_range: [18; 24), kind: NAMED_FIELD_DEF },
-                StructureNode { parent: None, label: "m", navigation_range: [32; 33), node_range: [28; 53), kind: MODULE },
-                StructureNode { parent: Some(2), label: "bar", navigation_range: [43; 46), node_range: [40; 51), kind: FN_DEF },
-                StructureNode { parent: None, label: "E", navigation_range: [60; 61), node_range: [55; 75), kind: ENUM_DEF },
-                StructureNode { parent: None, label: "T", navigation_range: [81; 82), node_range: [76; 88), kind: TYPE_DEF },
-                StructureNode { parent: None, label: "S", navigation_range: [96; 97), node_range: [89; 108), kind: STATIC_DEF },
-                StructureNode { parent: None, label: "C", navigation_range: [115; 116), node_range: [109; 127), kind: CONST_DEF },
-                StructureNode { parent: None, label: "impl E", navigation_range: [134; 135), node_range: [129; 138), kind: IMPL_ITEM },
-                StructureNode { parent: None, label: "impl fmt::Debug for E", navigation_range: [160; 161), node_range: [140; 164), kind: IMPL_ITEM }]"#,
-            &symbols,
-        )
-    }
-}
diff --git a/crates/ra_editor/src/typing.rs b/crates/ra_editor/src/typing.rs
index 21d068a7b..dd3d0f260 100644
--- a/crates/ra_editor/src/typing.rs
+++ b/crates/ra_editor/src/typing.rs
@@ -21,7 +21,7 @@ pub fn join_lines(file: &SourceFileNode, range: TextRange) -> LocalEdit {
            None => {
                return LocalEdit {
                    label: "join lines".to_string(),
-                    edit: TextEditBuilder::new().finish(),
+                    edit: TextEditBuilder::default().finish(),
                    cursor_position: None,
                };
            }
@@ -33,7 +33,7 @@ pub fn join_lines(file: &SourceFileNode, range: TextRange) -> LocalEdit {
    };
    let node = find_covering_node(file.syntax(), range);
-    let mut edit = TextEditBuilder::new();
+    let mut edit = TextEditBuilder::default();
    for node in node.descendants() {
        let text = match node.leaf_text() {
            Some(text) => text,
@@ -76,7 +76,7 @@ pub fn on_enter(file: &SourceFileNode, offset: TextUnit) -> Option<LocalEdit> {
    let indent = node_indent(file, comment.syntax())?;
    let inserted = format!("\n{}{} ", indent, prefix);
    let cursor_position = offset + TextUnit::of_str(&inserted);
-    let mut edit = TextEditBuilder::new();
+    let mut edit = TextEditBuilder::default();
    edit.insert(offset, inserted);
    Some(LocalEdit {
        label: "on enter".to_string(),
@@ -127,7 +127,7 @@ pub fn on_eq_typed(file: &SourceFileNode, offset: TextUnit) -> Option<LocalEdit>
        return None;
    }
    let offset = let_stmt.syntax().range().end();
-    let mut edit = TextEditBuilder::new();
+    let mut edit = TextEditBuilder::default();
    edit.insert(offset, ";".to_string());
    Some(LocalEdit {
        label: "add semicolon".to_string(),
diff --git a/crates/ra_hir/src/adt.rs b/crates/ra_hir/src/adt.rs
index e839a5a90..c6463235c 100644
--- a/crates/ra_hir/src/adt.rs
+++ b/crates/ra_hir/src/adt.rs
@@ -1,9 +1,10 @@
 use std::sync::Arc;
+use ra_db::Cancelable;
 use ra_syntax::ast::{self, NameOwner, StructFlavor};
 use crate::{
-    DefId, Cancelable, Name, AsName,
+    DefId, Name, AsName,
    db::HirDatabase,
    type_ref::TypeRef,
 };
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index 5a8ca3b47..73a4cdc5c 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -1,13 +1,14 @@
 use std::sync::Arc;
-use ra_syntax::SyntaxNode;
+use ra_syntax::{SyntaxNode, SourceFileNode};
-use ra_db::{SourceRootId, LocationIntener, SyntaxDatabase, FileId, Cancelable};
+use ra_db::{SourceRootId, LocationIntener, SyntaxDatabase, Cancelable};
 use crate::{
-    DefLoc, DefId, Name,
+    DefLoc, DefId, MacroCallLoc, MacroCallId, Name, HirFileId,
    SourceFileItems, SourceItemId,
    query_definitions,
    FnScopes,
+    macros::MacroExpansion,
    module::{ModuleId, ModuleTree, ModuleSource,
    nameres::{ItemMap, InputModuleItems}},
    ty::{InferenceResult, Ty},
@@ -18,7 +19,17 @@ salsa::query_group! {
 pub trait HirDatabase: SyntaxDatabase
    + AsRef<LocationIntener<DefLoc, DefId>>
+    + AsRef<LocationIntener<MacroCallLoc, MacroCallId>>
 {
+    fn hir_source_file(file_id: HirFileId) -> SourceFileNode {
+        type HirSourceFileQuery;
+        use fn HirFileId::hir_source_file;
+    }
+    fn expand_macro_invocation(invoc: MacroCallId) -> Option<Arc<MacroExpansion>> {
+        type