52 files changed, 132 insertions, 104 deletions
diff --git a/ARCHITECTURE.md b/ARCHITECTURE.md
index 277b29c12..9c404f4c3 100644
--- a/ARCHITECTURE.md
+++ b/ARCHITECTURE.md
@@ -15,7 +15,7 @@ More specifically, input data consists of a set of test files (`(PathBuf,
 String)` pairs) and an information about project structure, the so called
 `CrateGraph`. Crate graph specifies which files are crate roots, which cfg flags
 are specified for each crate (TODO: actually implement this) and what are
-dependencies between the crate. The analyzer keeps all these input data in
+dependencies between the crates. The analyzer keeps all these input data in
 memory and never does any IO. Because the input data is source code, which
 typically measures in tens of megabytes at most, keeping all input data in
 memory is OK.
@@ -74,9 +74,9 @@ notes.
 - `algo`: generic tree algorithms, including `walk` for O(1) stack
  space tree traversal (this is cool) and `visit` for type-driven
  visiting the nodes (this is double plus cool, if you understand how
-  `Visitor` works, you understand rust-analyzer).
+  `Visitor` works, you understand the design of syntax trees).
-Test for ra_syntax are mostly data-driven: `tests/data/parser` contains a bunch of `.rs`
+Tests for ra_syntax are mostly data-driven: `tests/data/parser` contains a bunch of `.rs`
 (test vectors) and `.txt` files with corresponding syntax trees. During testing, we check
 `.rs` against `.txt`. If the `.txt` file is missing, it is created (this is how you update
 tests). Additionally, running `cargo gen-tests` will walk the grammar module and collect
@@ -107,41 +107,46 @@ guessing a HIR for a particular source position.
 Underneath, HIR works on top of salsa, using a `HirDatabase` trait.
-### `crates/ra_analysis`
+### `crates/ra_ide_api`
-A stateful library for analyzing many Rust files as they change.
+A stateful library for analyzing many Rust files as they change. `AnalysisHost`
-`AnalysisHost` is a mutable entity (clojure's atom) which holds the
+is a mutable entity (clojure's atom) which holds the current state, incorporates
-current state, incorporates changes and handles out `Analysis` --- an
+changes and handles out `Analysis` --- an immutable and consistent snapshot of
-immutable and consistent snapshot of world state at a point in time, which
+world state at a point in time, which actually powers analysis.
-actually powers analysis.
-One interesting aspect of analysis is its support for cancellation. When a change
+One interesting aspect of analysis is its support for cancellation. When a
-is applied to `AnalysisHost`, first all currently active snapshots are
+change is applied to `AnalysisHost`, first all currently active snapshots are
 cancelled. Only after all snapshots are dropped the change actually affects the
 database.
-### `crates/ra_lsp_server`
+APIs in this crate are IDE centric: they take text offsets as input and produce
+offsets and strings as output. This works on top of rich code model powered by
-An LSP implementation which uses `ra_analysis` for managing state and
+`hir`.
-`ra_editor` for actually doing useful stuff.
-See [#79](https://github.com/rust-analyzer/rust-analyzer/pull/79/) as an
-example of PR which adds a new feature to `ra_editor` and exposes it
-to `ra_lsp_server`.
-### `crates/ra_editor`
+### `crates/ra_ide_api_light`
-All IDE features which can be implemented if you only have access to a
+All IDE features which can be implemented if you only have access to a single
-single file. `ra_editor` could be used to enhance editing of Rust code
+file. `ra_ide_api_light` could be used to enhance editing of Rust code without
-without the need to fiddle with build-systems, file
+the need to fiddle with build-systems, file synchronization and such.
-synchronization and such.
-In a sense, `ra_editor` is just a bunch of pure functions which take a
+In a sense, `ra_ide_api_light` is just a bunch of pure functions which take a
 syntax tree as input.
-The tests for `ra_editor` are `#[cfg(test)] mod tests` unit-tests spread
+The tests for `ra_ide_api_light` are `#[cfg(test)] mod tests` unit-tests spread
 throughout its modules.
+### `crates/ra_lsp_server`
+An LSP implementation which wraps `ra_ide_api` into a langauge server protocol.
+### `crates/ra_vfs`
+Although `hir` and `ra_ide_api` don't do any io, we need to be able to read
+files from disk at the end of the day. This is what `ra_vfs` does. It also
+manages overlays: "dirty" files in the editor, whose "true" contents is
+different from data on disk.
 ### `crates/gen_lsp_server`
 A language server scaffold, exposing a synchronous crossbeam-channel based API.
diff --git a/Cargo.lock b/Cargo.lock
index f1d8e5462..354cc138b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -171,7 +171,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "crossbeam-utils 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "smallvec 0.6.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -548,7 +548,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "smallvec 0.6.7 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -637,27 +637,6 @@ dependencies = [
 ]
 [[package]]
-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 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "ra_db 0.1.0",
- "ra_editor 0.1.0",
- "ra_hir 0.1.0",
- "ra_syntax 0.1.0",
- "ra_text_edit 0.1.0",
- "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)",
- "salsa 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "test_utils 0.1.0",
- "unicase 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-[[package]]
 name = "ra_arena"
 version = "0.1.0"
@@ -668,7 +647,7 @@ dependencies = [
 "clap 2.32.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 "join_to_string 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "ra_editor 0.1.0",
+ "ra_ide_api_light 0.1.0",
 "ra_syntax 0.1.0",
 "tools 0.1.0",
 ]
@@ -687,35 +666,56 @@ dependencies = [
 ]
 [[package]]
-name = "ra_editor"
+name = "ra_hir"
 version = "0.1.0"
 dependencies = [
- "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "arrayvec 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "join_to_string 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "proptest 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "flexi_logger 0.10.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ra_arena 0.1.0",
+ "ra_db 0.1.0",
 "ra_syntax 0.1.0",
- "ra_text_edit 0.1.0",
+ "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)",
- "superslice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "salsa 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "test_utils 0.1.0",
 ]
 [[package]]
-name = "ra_hir"
+name = "ra_ide_api"
 version = "0.1.0"
 dependencies = [
- "arrayvec 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fst 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "flexi_logger 0.10.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "ra_arena 0.1.0",
 "ra_db 0.1.0",
+ "ra_hir 0.1.0",
+ "ra_ide_api_light 0.1.0",
 "ra_syntax 0.1.0",
+ "ra_text_edit 0.1.0",
+ "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)",
 "salsa 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "test_utils 0.1.0",
+ "unicase 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+[[package]]
+name = "ra_ide_api_light"
+version = "0.1.0"
+dependencies = [
+ "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "join_to_string 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proptest 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ra_syntax 0.1.0",
+ "ra_text_edit 0.1.0",
+ "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "superslice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "test_utils 0.1.0",
 ]
 [[package]]
@@ -733,7 +733,7 @@ dependencies = [
 "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)",
 "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "ra_analysis 0.1.0",
+ "ra_ide_api 0.1.0",
 "ra_syntax 0.1.0",
 "ra_text_edit 0.1.0",
 "ra_vfs 0.1.0",
@@ -806,7 +806,7 @@ dependencies = [
 [[package]]
 name = "rand"
-version = "0.6.3"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "autocfg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -815,7 +815,7 @@ dependencies = [
 "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_os 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_os 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_pcg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -861,13 +861,14 @@ dependencies = [
 [[package]]
 name = "rand_os"
-version = "0.1.0"
+version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -910,6 +911,14 @@ dependencies = [
 ]
 [[package]]
+name = "rdrand"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+[[package]]
 name = "redox_syscall"
 version = "0.1.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1164,7 +1173,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.4 (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)",
@@ -1551,17 +1560,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
 "checksum quote 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)" = "53fa22a1994bd0f9372d7a816207d8a2677ad0325b073f5c5332760f0fb62b5c"
 "checksum rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e464cd887e869cddcae8792a4ee31d23c7edd516700695608f5b98c67ee0131c"
-"checksum rand 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "b65e163105a6284f841bd23100a015895f54340e88a5ffc9ca7b8b33827cfce0"
+"checksum rand 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3906503e80ac6cbcacb2c2973fa8e473f24d7e2747c8c92bb230c2441cad96b5"
 "checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
 "checksum rand_core 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1961a422c4d189dfb50ffa9320bf1f2a9bd54ecb92792fb9477f99a1045f3372"
 "checksum rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0905b6b7079ec73b314d4c748701f6931eb79fd97c668caa3f1899b22b32c6db"
 "checksum rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
 "checksum rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ded997c9d5f13925be2a6fd7e66bf1872597f759fd9dd93513dd7e92e5a5ee08"
-"checksum rand_os 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "de5ac4de1c2973e1391dc305cb0fbf8788cb58068e98255439b7485a77022273"
+"checksum rand_os 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f46fbd5550acf75b0c2730f5dd1873751daf9beb8f11b44027778fae50d7feca"
 "checksum rand_pcg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "086bd09a33c7044e56bb44d5bdde5a60e7f119a9e95b0775f545de759a32fe05"
 "checksum rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cbf7e9e623549b0e21f6e97cf8ecf247c1a8fd2e8a992ae265314300b2455d5c"
 "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 rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2"
 "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"
diff --git a/crates/ra_cli/Cargo.toml b/crates/ra_cli/Cargo.toml
index 83f1d91e0..eb1722d5e 100644
--- a/crates/ra_cli/Cargo.toml
+++ b/crates/ra_cli/Cargo.toml
@@ -10,5 +10,5 @@ clap = "2.32.0"
 failure = "0.1.4"
 join_to_string = "0.1.1"
 ra_syntax = { path = "../ra_syntax" }
-ra_editor = { path = "../ra_editor" }
+ra_ide_api_light = { path = "../ra_ide_api_light" }
 tools = { path = "../tools" }
diff --git a/crates/ra_cli/src/main.rs b/crates/ra_cli/src/main.rs
index 0d12f3a88..43fb2fc4c 100644
--- a/crates/ra_cli/src/main.rs
+++ b/crates/ra_cli/src/main.rs
@@ -2,7 +2,7 @@ use std::{fs, io::Read, path::Path, time::Instant};
 use clap::{App, Arg, SubCommand};
 use join_to_string::join;
-use ra_editor::{extend_selection, file_structure, syntax_tree};
+use ra_ide_api_light::{extend_selection, file_structure, syntax_tree};
 use ra_syntax::{SourceFile, TextRange, TreePtr, AstNode};
 use tools::collect_tests;
diff --git a/crates/ra_db/src/lib.rs b/crates/ra_db/src/lib.rs
index f56f70983..e680d9fc3 100644
--- a/crates/ra_db/src/lib.rs
+++ b/crates/ra_db/src/lib.rs
@@ -1,4 +1,4 @@
-//! ra_db defines basic database traits. Concrete DB is defined by ra_analysis.
+//! ra_db defines basic database traits. Concrete DB is defined by ra_ide_api.
 mod cancelation;
 mod syntax_ptr;
 mod input;
diff --git a/crates/ra_analysis/Cargo.toml b/crates/ra_ide_api/Cargo.toml
index 11c78ced8..d42a664b6 100644
--- a/crates/ra_analysis/Cargo.toml
+++ b/crates/ra_ide_api/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 edition = "2018"
-name = "ra_analysis"
+name = "ra_ide_api"
 version = "0.1.0"
 authors = ["Aleksey Kladov <[email protected]>"]
@@ -16,7 +16,7 @@ parking_lot = "0.7.0"
 unicase = "2.2.0"
 ra_syntax = { path = "../ra_syntax" }
-ra_editor = { path = "../ra_editor" }
+ra_ide_api_light = { path = "../ra_ide_api_light" }
 ra_text_edit = { path = "../ra_text_edit" }
 ra_db = { path = "../ra_db" }
 hir = { path = "../ra_hir", package = "ra_hir" }
diff --git a/crates/ra_analysis/src/call_info.rs b/crates/ra_ide_api/src/call_info.rs
index 27b760780..27b760780 100644
--- a/crates/ra_analysis/src/call_info.rs
+++ b/crates/ra_ide_api/src/call_info.rs
diff --git a/crates/ra_analysis/src/completion.rs b/crates/ra_ide_api/src/completion.rs
index ce777a771..ce777a771 100644
--- a/crates/ra_analysis/src/completion.rs
+++ b/crates/ra_ide_api/src/completion.rs
diff --git a/crates/ra_analysis/src/completion/complete_dot.rs b/crates/ra_ide_api/src/completion/complete_dot.rs
index 5d4e60dc5..5d4e60dc5 100644
--- a/crates/ra_analysis/src/completion/complete_dot.rs
+++ b/crates/ra_ide_api/src/completion/complete_dot.rs
diff --git a/crates/ra_analysis/src/completion/complete_fn_param.rs b/crates/ra_ide_api/src/completion/complete_fn_param.rs
index c1739e47e..c1739e47e 100644
--- a/crates/ra_analysis/src/completion/complete_fn_param.rs
+++ b/crates/ra_ide_api/src/completion/complete_fn_param.rs
diff --git a/crates/ra_analysis/src/completion/complete_keyword.rs b/crates/ra_ide_api/src/completion/complete_keyword.rs
index d350f06ce..d350f06ce 100644
--- a/crates/ra_analysis/src/completion/complete_keyword.rs
+++ b/crates/ra_ide_api/src/completion/complete_keyword.rs
diff --git a/crates/ra_analysis/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index 4723a65a6..4723a65a6 100644
--- a/crates/ra_analysis/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
diff --git a/crates/ra_analysis/src/completion/complete_scope.rs b/crates/ra_ide_api/src/completion/complete_scope.rs
index ee9052d3d..ee9052d3d 100644
--- a/crates/ra_analysis/src/completion/complete_scope.rs
+++ b/crates/ra_ide_api/src/completion/complete_scope.rs
diff --git a/crates/ra_analysis/src/completion/complete_snippet.rs b/crates/ra_ide_api/src/completion/complete_snippet.rs
index a495751dd..a495751dd 100644
--- a/crates/ra_analysis/src/completion/complete_snippet.rs
+++ b/crates/ra_ide_api/src/completion/complete_snippet.rs
diff --git a/crates/ra_analysis/src/completion/completion_context.rs b/crates/ra_ide_api/src/completion/completion_context.rs
index 01786bb69..01786bb69 100644
--- a/crates/ra_analysis/src/completion/completion_context.rs
+++ b/crates/ra_ide_api/src/completion/completion_context.rs
diff --git a/crates/ra_analysis/src/completion/completion_item.rs b/crates/ra_ide_api/src/completion/completion_item.rs
index a25b87bee..a25b87bee 100644
--- a/crates/ra_analysis/src/completion/completion_item.rs
+++ b/crates/ra_ide_api/src/completion/completion_item.rs
diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_ide_api/src/db.rs
index 9d46609ec..9d46609ec 100644
--- a/crates/ra_analysis/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
diff --git a/crates/ra_analysis/src/extend_selection.rs b/crates/ra_ide_api/src/extend_selection.rs
index 3b130f966..c3c809c9f 100644
--- a/crates/ra_analysis/src/extend_selection.rs
+++ b/crates/ra_ide_api/src/extend_selection.rs
@@ -14,7 +14,7 @@ pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRang
    if let Some(range) = extend_selection_in_macro(db, &source_file, frange) {
        return range;
    }
-    ra_editor::extend_selection(source_file.syntax(), frange.range).unwrap_or(frange.range)
+    ra_ide_api_light::extend_selection(source_file.syntax(), frange.range).unwrap_or(frange.range)
 }
 fn extend_selection_in_macro(
@@ -25,7 +25,7 @@ fn extend_selection_in_macro(
    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(), dst_range)?;
+    let dst_range = ra_ide_api_light::extend_selection(&exp.syntax(), dst_range)?;
    let src_range = exp.map_range_back(dst_range)? + off;
    Some(src_range)
 }
diff --git a/crates/ra_analysis/src/goto_defenition.rs b/crates/ra_ide_api/src/goto_defenition.rs
index fcd8d315e..fcd8d315e 100644
--- a/crates/ra_analysis/src/goto_defenition.rs
+++ b/crates/ra_ide_api/src/goto_defenition.rs
diff --git a/crates/ra_analysis/src/hover.rs b/crates/ra_ide_api/src/hover.rs
index 475524ee1..475524ee1 100644
--- a/crates/ra_analysis/src/hover.rs
+++ b/crates/ra_ide_api/src/hover.rs
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_ide_api/src/imp.rs
index 2b9963b3c..7c60ab7d6 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_ide_api/src/imp.rs
@@ -6,7 +6,7 @@ use hir::{
    self, Problem, source_binder,
 };
 use ra_db::{FilesDatabase, SourceRoot, SourceRootId, SyntaxDatabase};
-use ra_editor::{self, assists, LocalEdit, Severity};
+use ra_ide_api_light::{self, assists, LocalEdit, Severity};
 use ra_syntax::{
    TextRange, AstNode, SourceFile,
    ast::{self, NameOwner},
@@ -194,7 +194,7 @@ impl db::RootDatabase {
    pub(crate) fn diagnostics(&self, file_id: FileId) -> Cancelable<Vec<Diagnostic>> {
        let syntax = self.source_file(file_id);
-        let mut res = ra_editor::diagnostics(&syntax)
+        let mut res = ra_ide_api_light::diagnostics(&syntax)
            .into_iter()
            .map(|d| Diagnostic {
                range: d.range,
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index 48df08416..7e9ca2034 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -1,8 +1,14 @@
-//! ra_analyzer crate provides "ide-centric" APIs for the rust-analyzer. What
+//! ra_ide_api crate provides "ide-centric" APIs for the rust-analyzer. That is,
-//! powers this API are the `RootDatabase` struct, which defines a `salsa`
+//! it generally operates with files and text ranges, and returns results as
+//! Strings, suitable for displaying to the human.
+//!
+//! What 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.
+//!
+//! The sibling `ra_ide_api_light` handles thouse bits of IDE functionality
+//! which are restricted to a single file and need only syntax.
 macro_rules! ctry {
    ($expr:expr) => {
        match $expr {
@@ -44,7 +50,7 @@ pub use crate::{
    completion::{CompletionItem, CompletionItemKind, InsertText},
    runnables::{Runnable, RunnableKind},
 };
-pub use ra_editor::{
+pub use ra_ide_api_light::{
    Fold, FoldKind, HighlightedRange, Severity, StructureNode,
    LineIndex, LineCol, translate_offset_with_edit,
 };
@@ -336,25 +342,28 @@ impl Analysis {
    /// Returns position of the mathcing brace (all types of braces are
    /// supported).
    pub fn matching_brace(&self, file: &SourceFile, offset: TextUnit) -> Option<TextUnit> {
-        ra_editor::matching_brace(file, offset)
+        ra_ide_api_light::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.db.source_file(file_id);
-        ra_editor::syntax_tree(&file)
+        ra_ide_api_light::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.db.source_file(frange.file_id);
-        SourceChange::from_local_edit(frange.file_id, ra_editor::join_lines(&file, frange.range))
+        SourceChange::from_local_edit(
+            frange.file_id,
+            ra_ide_api_light::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.db.source_file(position.file_id);
-        let edit = ra_editor::on_enter(&file, position.offset)?;
+        let edit = ra_ide_api_light::on_enter(&file, position.offset)?;
        Some(SourceChange::from_local_edit(position.file_id, edit))
    }
    /// Returns an edit which should be applied after `=` was typed. Primarily,
@@ -362,25 +371,25 @@ impl Analysis {
    // FIXME: use a snippet completion instead of this hack here.
    pub fn on_eq_typed(&self, position: FilePosition) -> Option<SourceChange> {
        let file = self.db.source_file(position.file_id);
-        let edit = ra_editor::on_eq_typed(&file, position.offset)?;
+        let edit = ra_ide_api_light::on_eq_typed(&file, position.offset)?;
        Some(SourceChange::from_local_edit(position.file_id, edit))
    }
    /// Returns an edit which should be applied when a dot ('.') is typed on a blank line, indenting the line appropriately.
    pub fn on_dot_typed(&self, position: FilePosition) -> Option<SourceChange> {
        let file = self.db.source_file(position.file_id);
-        let edit = ra_editor::on_dot_typed(&file, position.offset)?;
+        let edit = ra_ide_api_light::on_dot_typed(&file, position.offset)?;
        Some(SourceChange::from_local_edit(position.file_id, edit))
    }
    /// 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.db.source_file(file_id);
-        ra_editor::file_structure(&file)
+        ra_ide_api_light::file_structure(&file)
    }
    /// Returns the set of folding ranges.
    pub fn folding_ranges(&self, file_id: FileId) -> Vec<Fold> {
        let file = self.db.source_file(file_id);
-        ra_editor::folding_ranges(&file)
+        ra_ide_api_light::folding_ranges(&file)
    }
    /// Fuzzy searches for a symbol.
    pub fn symbol_search(&self, query: Query) -> Cancelable<Vec<NavigationTarget>> {
diff --git a/crates/ra_analysis/src/mock_analysis.rs b/crates/ra_ide_api/src/mock_analysis.rs
index 846c76cfe..846c76cfe 100644
--- a/crates/ra_analysis/src/mock_analysis.rs
+++ b/crates/ra_ide_api/src/mock_analysis.rs
diff --git a/crates/ra_analysis/src/runnables.rs b/crates/ra_ide_api/src/runnables.rs
index 98b1d2d55..98b1d2d55 100644
--- a/crates/ra_analysis/src/runnables.rs
+++ b/crates/ra_ide_api/src/runnables.rs
diff --git a/crates/ra_analysis/src/symbol_index.rs b/crates/ra_ide_api/src/symbol_index.rs
index 8dd15b40e..8dd15b40e 100644
--- a/crates/ra_analysis/src/symbol_index.rs
+++ b/crates/ra_ide_api/src/symbol_index.rs
diff --git a/crates/ra_analysis/src/syntax_highlighting.rs b/crates/ra_ide_api/src/syntax_highlighting.rs
index d2dc6cfbb..cb19e9515 100644
--- a/crates/ra_analysis/src/syntax_highlighting.rs
+++ b/crates/ra_ide_api/src/syntax_highlighting.rs
@@ -1,22 +1,21 @@
 use ra_syntax::{ast, AstNode,};
-use ra_editor::HighlightedRange;
 use ra_db::SyntaxDatabase;
 use crate::{
+    FileId, Cancelable, HighlightedRange,
    db::RootDatabase,
-    FileId, Cancelable,
 };
 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.syntax());
+    let mut res = ra_ide_api_light::highlight(source_file.syntax());
    for macro_call in source_file
        .syntax()
        .descendants()
        .filter_map(ast::MacroCall::cast)
    {
        if let Some((off, exp)) = hir::MacroDef::ast_expand(macro_call) {
-            let mapped_ranges = ra_editor::highlight(&exp.syntax())
+            let mapped_ranges = ra_ide_api_light::highlight(&exp.syntax())
                .into_iter()
                .filter_map(|r| {
                    let mapped_range = exp.map_range_back(r.range)?;
diff --git a/crates/ra_analysis/tests/test/main.rs b/crates/ra_ide_api/tests/test/main.rs
index 2c0735cb5..d1dc07e5b 100644
--- a/crates/ra_analysis/tests/test/main.rs
+++ b/crates/ra_ide_api/tests/test/main.rs
@@ -3,7 +3,7 @@ mod runnables;
 use ra_syntax::TextRange;
 use test_utils::{assert_eq_dbg, assert_eq_text};
-use ra_analysis::{
+use ra_ide_api::{
    mock_analysis::{analysis_and_position, single_file, single_file_with_position, MockAnalysis},
    AnalysisChange, CrateGraph, FileId, Query
 };
diff --git a/crates/ra_analysis/tests/test/runnables.rs b/crates/ra_ide_api/tests/test/runnables.rs
index e6e0afbc3..da8d5e0d5 100644
--- a/crates/ra_analysis/tests/test/runnables.rs
+++ b/crates/ra_ide_api/tests/test/runnables.rs
@@ -1,6 +1,6 @@
 use test_utils::assert_eq_dbg;
-use ra_analysis::mock_analysis::analysis_and_position;
+use ra_ide_api::mock_analysis::analysis_and_position;
 #[test]
 fn test_runnables() {
diff --git a/crates/ra_editor/Cargo.toml b/crates/ra_ide_api_light/Cargo.toml
index a97d2308f..8c192fca6 100644
--- a/crates/ra_editor/Cargo.toml
+++ b/crates/ra_ide_api_light/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 edition = "2018"
-name = "ra_editor"
+name = "ra_ide_api_light"
 version = "0.1.0"
 authors = ["Aleksey Kladov <[email protected]>"]
 publish = false
diff --git a/crates/ra_editor/src/assists.rs b/crates/ra_ide_api_light/src/assists.rs
index 83eabfc85..83eabfc85 100644
--- a/crates/ra_editor/src/assists.rs
+++ b/crates/ra_ide_api_light/src/assists.rs
diff --git a/crates/ra_editor/src/assists/add_derive.rs b/crates/ra_ide_api_light/src/assists/add_derive.rs
index 6e964d011..6e964d011 100644
--- a/crates/ra_editor/src/assists/add_derive.rs
+++ b/crates/ra_ide_api_light/src/assists/add_derive.rs
diff --git a/crates/ra_editor/src/assists/add_impl.rs b/crates/ra_ide_api_light/src/assists/add_impl.rs
index 2eda7cae2..2eda7cae2 100644
--- a/crates/ra_editor/src/assists/add_impl.rs
+++ b/crates/ra_ide_api_light/src/assists/add_impl.rs
diff --git a/crates/ra_editor/src/assists/change_visibility.rs b/crates/ra_ide_api_light/src/assists/change_visibility.rs
index 89729e2c2..89729e2c2 100644
--- a/crates/ra_editor/src/assists/change_visibility.rs
+++ b/crates/ra_ide_api_light/src/assists/change_visibility.rs
diff --git a/crates/ra_editor/src/assists/flip_comma.rs b/crates/ra_ide_api_light/src/assists/flip_comma.rs
index a343413cc..a343413cc 100644
--- a/crates/ra_editor/src/assists/flip_comma.rs
+++ b/crates/ra_ide_api_light/src/assists/flip_comma.rs
diff --git a/crates/ra_editor/src/assists/introduce_variable.rs b/crates/ra_ide_api_light/src/assists/introduce_variable.rs
index 523ec7034..523ec7034 100644
--- a/crates/ra_editor/src/assists/introduce_variable.rs
+++ b/crates/ra_ide_api_light/src/assists/introduce_variable.rs
diff --git a/crates/ra_editor/src/assists/replace_if_let_with_match.rs b/crates/ra_ide_api_light/src/assists/replace_if_let_with_match.rs
index 30c371480..30c371480 100644
--- a/crates/ra_editor/src/assists/replace_if_let_with_match.rs
+++ b/crates/ra_ide_api_light/src/assists/replace_if_let_with_match.rs
diff --git a/crates/ra_editor/src/assists/split_import.rs b/crates/ra_ide_api_light/src/assists/split_import.rs
index e4015f07d..e4015f07d 100644
--- a/crates/ra_editor/src/assists/split_import.rs
+++ b/crates/ra_ide_api_light/src/assists/split_import.rs
diff --git a/crates/ra_editor/src/diagnostics.rs b/crates/ra_ide_api_light/src/diagnostics.rs
index 2b695dfdf..2b695dfdf 100644
--- a/crates/ra_editor/src/diagnostics.rs
+++ b/crates/ra_ide_api_light/src/diagnostics.rs
diff --git a/crates/ra_editor/src/extend_selection.rs b/crates/ra_ide_api_light/src/extend_selection.rs
index 08cae5a51..08cae5a51 100644
--- a/crates/ra_editor/src/extend_selection.rs
+++ b/crates/ra_ide_api_light/src/extend_selection.rs
diff --git a/crates/ra_editor/src/folding_ranges.rs b/crates/ra_ide_api_light/src/folding_ranges.rs
index 6f3106889..6f3106889 100644
--- a/crates/ra_editor/src/folding_ranges.rs
+++ b/crates/ra_ide_api_light/src/folding_ranges.rs
diff --git a/crates/ra_editor/src/lib.rs b/crates/ra_ide_api_light/src/lib.rs
index 5a6af19b7..40638eda8 100644
--- a/crates/ra_editor/src/lib.rs
+++ b/crates/ra_ide_api_light/src/lib.rs
@@ -1,3 +1,8 @@
+//! This crate provides thouse IDE features which use only a single file.
+//!
+//! This usually means functions which take sytnax tree as an input and produce
+//! an edit or some auxilarly info.
 pub mod assists;
 mod extend_selection;
 mod folding_ranges;
diff --git a/crates/ra_editor/src/line_index.rs b/crates/ra_ide_api_light/src/line_index.rs
index 898fee7e0..898fee7e0 100644
--- a/crates/ra_editor/src/line_index.rs
+++ b/crates/ra_ide_api_light/src/line_index.rs
diff --git a/crates/ra_editor/src/line_index_utils.rs b/crates/ra_ide_api_light/src/line_index_utils.rs
index ec3269bbb..ec3269bbb 100644
--- a/crates/ra_editor/src/line_index_utils.rs
+++ b/crates/ra_ide_api_light/src/line_index_utils.rs
diff --git a/crates/ra_editor/src/structure.rs b/crates/ra_ide_api_light/src/structure.rs
index 8bd57555f..8bd57555f 100644
--- a/crates/ra_editor/src/structure.rs
+++ b/crates/ra_ide_api_light/src/structure.rs
diff --git a/crates/ra_editor/src/test_utils.rs b/crates/ra_ide_api_light/src/test_utils.rs
index dc2470aa3..dc2470aa3 100644
--- a/crates/ra_editor/src/test_utils.rs
+++ b/crates/ra_ide_api_light/src/test_utils.rs
diff --git a/crates/ra_editor/src/typing.rs b/crates/ra_ide_api_light/src/typing.rs
index d8177f245..d8177f245 100644
--- a/crates/ra_editor/src/typing.rs
+++ b/crates/ra_ide_api_light/src/typing.rs
diff --git a/crates/ra_lsp_server/Cargo.toml b/crates/ra_lsp_server/Cargo.toml
index b9fd61105..296fae34f 100644
--- a/crates/ra_lsp_server/Cargo.toml
+++ b/crates/ra_lsp_server/Cargo.toml
@@ -29,7 +29,7 @@ parking_lot = "0.7.0"
 thread_worker = { path = "../thread_worker" }
 ra_syntax = { path = "../ra_syntax" }
 ra_text_edit = { path = "../ra_text_edit" }
-ra_analysis = { path = "../ra_analysis" }
+ra_ide_api = { path = "../ra_ide_api" }
 gen_lsp_server = { path = "../gen_lsp_server" }
 ra_vfs = { path = "../ra_vfs" }
diff --git a/crates/ra_lsp_server/src/conv.rs b/crates/ra_lsp_server/src/conv.rs
index b3f8c83cc..5c8b3c194 100644
--- a/crates/ra_lsp_server/src/conv.rs
+++ b/crates/ra_lsp_server/src/conv.rs
@@ -4,7 +4,7 @@ use languageserver_types::{
    TextDocumentItem, TextDocumentPositionParams, Url, VersionedTextDocumentIdentifier,
    WorkspaceEdit,
 };
-use ra_analysis::{
+use ra_ide_api::{
    CompletionItem, CompletionItemKind, FileId, FilePosition, FileRange, FileSystemEdit,
    InsertText, NavigationTarget, SourceChange, SourceFileEdit,
    LineCol, LineIndex, translate_offset_with_edit
diff --git a/crates/ra_lsp_server/src/main_loop.rs b/crates/ra_lsp_server/src/main_loop.rs
index 2dc1be26a..96923fac7 100644
--- a/crates/ra_lsp_server/src/main_loop.rs
+++ b/crates/ra_lsp_server/src/main_loop.rs
@@ -10,7 +10,7 @@ use gen_lsp_server::{
    handle_shutdown, ErrorCode, RawMessage, RawNotification, RawRequest, RawResponse,
 };
 use languageserver_types::NumberOrString;
-use ra_analysis::{Canceled, FileId, LibraryData};
+use ra_ide_api::{Canceled, FileId, LibraryData};
 use ra_vfs::VfsTask;
 use rayon;
 use rustc_hash::FxHashSet;
diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index b7777bfc3..a653c5ada 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -8,7 +8,7 @@ use languageserver_types::{
    ParameterInformation, ParameterLabel, Position, PrepareRenameResponse, Range, RenameParams,
    SignatureInformation, SymbolInformation, TextDocumentIdentifier, TextEdit, WorkspaceEdit,
 };
-use ra_analysis::{
+use ra_ide_api::{
    FileId, FilePosition, FileRange, FoldKind, Query, RunnableKind, Severity, SourceChange,
 };
 use ra_syntax::{TextUnit, AstNode};
@@ -736,7 +736,7 @@ fn highlight(world: &ServerWorld, file_id: FileId) -> Result<Vec<Decoration>> {
 }
 fn to_diagnostic_severity(severity: Severity) -> DiagnosticSeverity {
-    use ra_analysis::Severity::*;
+    use ra_ide_api::Severity::*;
    match severity {
        Error => DiagnosticSeverity::Error,
diff --git a/crates/ra_lsp_server/src/main_loop/subscriptions.rs b/crates/ra_lsp_server/src/main_loop/subscriptions.rs
index 03f41e870..a83e01557 100644
--- a/crates/ra_lsp_server/src/main_loop/subscriptions.rs
+++ b/crates/ra_lsp_server/src/main_loop/subscriptions.rs
@@ -1,4 +1,4 @@
-use ra_analysis::FileId;
+use ra_ide_api::FileId;
 use rustc_hash::FxHashSet;
 pub struct Subscriptions {
diff --git a/crates/ra_lsp_server/src/server_world.rs b/crates/ra_lsp_server/src/server_world.rs
index ebf2b15cc..76c76766d 100644
--- a/crates/ra_lsp_server/src/server_world.rs
+++ b/crates/ra_lsp_server/src/server_world.rs
@@ -1,10 +1,10 @@
 use std::{
-    path::{PathBuf},
+    path::PathBuf,
    sync::Arc,
 };
 use languageserver_types::Url;
-use ra_analysis::{
+use ra_ide_api::{
    Analysis, AnalysisChange, AnalysisHost, CrateGraph, FileId, LibraryData,
    SourceRootId
 };
@@ -12,7 +12,7 @@ use ra_vfs::{Vfs, VfsChange, VfsFile, VfsRoot};
 use rustc_hash::FxHashMap;
 use relative_path::RelativePathBuf;
 use parking_lot::RwLock;
-use failure::{format_err};
+use failure::format_err;
 use crate::{
    project_model::{CargoWorkspace, TargetKind},