12 files changed, 251 insertions, 10 deletions

diff --git a/.travis.yml b/.travis.yml
index 7d66f72d8..af71a9cce 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,7 +14,6 @@ matrix:
           script:
               - rustup component add rustfmt
               - rustup component add rust-src
-              - sed -i "s/debug = 1/debug = false/g" Cargo.toml
               - cargo test --no-run  # let's measure compile time separately
               - cargo test
           env:
diff --git a/Cargo.toml b/Cargo.toml
index 97c02b40f..5c57020f7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,9 @@
 members = [ "crates/*", "xtask/" ]
 
 [profile.dev]
-debug = 1 # only line info
+# disabling debug info speeds up builds a bunch,
+# and we don't rely on it for debugging that much.
+debug = 0
 
 [profile.release]
 incremental = true
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 131f6c797..9dc8d139b 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -76,7 +76,11 @@ pub use crate::{
     resolve::ScopeDef,
     source_binder::{PathResolution, ScopeEntryWithSyntax, SourceAnalyzer},
     ty::{
-        display::HirDisplay, ApplicationTy, CallableDef, Substs, TraitRef, Ty, TypeCtor, TypeWalk,
+        display::HirDisplay,
+        primitive::{
+            FloatBitness, FloatTy, IntBitness, IntTy, Signedness, UncertainFloatTy, UncertainIntTy,
+        },
+        ApplicationTy, CallableDef, Substs, TraitRef, Ty, TypeCtor, TypeWalk,
     },
 };
 
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 7e6083961..6db9937a4 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -36,11 +36,12 @@ pub(super) fn collect_defs(db: &impl DefDatabase2, mut def_map: CrateDefMap) ->
         );
 
         // look for the prelude
-        if def_map.prelude.is_none() {
-            let map = db.crate_def_map(dep.crate_id);
-            if map.prelude.is_some() {
-                def_map.prelude = map.prelude;
-            }
+        // If the dependency defines a prelude, we overwrite an already defined
+        // prelude. This is necessary to import the "std" prelude if a crate
+        // depends on both "core" and "std".
+        let dep_def_map = db.crate_def_map(dep.crate_id);
+        if dep_def_map.prelude.is_some() {
+            def_map.prelude = dep_def_map.prelude;
         }
     }
 
diff --git a/crates/ra_hir_def/src/nameres/tests.rs b/crates/ra_hir_def/src/nameres/tests.rs
index 52bd0aa91..256f7d4be 100644
--- a/crates/ra_hir_def/src/nameres/tests.rs
+++ b/crates/ra_hir_def/src/nameres/tests.rs
@@ -464,6 +464,37 @@ fn values_dont_shadow_extern_crates() {
 }
 
 #[test]
+fn std_prelude_takes_precedence_above_core_prelude() {
+    let map = def_map(
+        r#"
+        //- /main.rs crate:main deps:core,std
+        use {Foo, Bar};
+
+        //- /std.rs crate:std deps:core
+        #[prelude_import]
+        pub use self::prelude::*;
+        mod prelude {
+            pub struct Foo;
+            pub use core::prelude::Bar;
+        }
+
+        //- /core.rs crate:core
+        #[prelude_import]
+        pub use self::prelude::*;
+        mod prelude {
+            pub struct Bar;
+        }
+        "#,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮Foo: t v
+    "###);
+}
+
+#[test]
 fn cfg_not_test() {
     let map = def_map(
         r#"
diff --git a/crates/ra_ide_api/src/completion/complete_scope.rs b/crates/ra_ide_api/src/completion/complete_scope.rs
index 4e56de3f5..3e205efd1 100644
--- a/crates/ra_ide_api/src/completion/complete_scope.rs
+++ b/crates/ra_ide_api/src/completion/complete_scope.rs
@@ -598,6 +598,68 @@ mod tests {
     }
 
     #[test]
+    fn completes_std_prelude_if_core_is_defined() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                "
+                //- /main.rs
+                fn foo() { let x: <|> }
+
+                //- /core/lib.rs
+                #[prelude_import]
+                use prelude::*;
+
+                mod prelude {
+                    struct Option;
+                }
+
+                //- /std/lib.rs
+                #[prelude_import]
+                use prelude::*;
+
+                mod prelude {
+                    struct String;
+                }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "String",
+                source_range: [18; 18),
+                delete: [18; 18),
+                insert: "String",
+                kind: Struct,
+            },
+            CompletionItem {
+                label: "core",
+                source_range: [18; 18),
+                delete: [18; 18),
+                insert: "core",
+                kind: Module,
+            },
+            CompletionItem {
+                label: "foo()",
+                source_range: [18; 18),
+                delete: [18; 18),
+                insert: "foo()$0",
+                kind: Function,
+                lookup: "foo",
+                detail: "fn foo()",
+            },
+            CompletionItem {
+                label: "std",
+                source_range: [18; 18),
+                delete: [18; 18),
+                insert: "std",
+                kind: Module,
+            },
+        ]
+        "###
+        );
+    }
+
+    #[test]
     fn completes_macros_as_value() {
         assert_debug_snapshot!(
             do_reference_completion(
diff --git a/crates/ra_project_model/src/lib.rs b/crates/ra_project_model/src/lib.rs
index 8b8663a78..0e14f1b70 100644
--- a/crates/ra_project_model/src/lib.rs
+++ b/crates/ra_project_model/src/lib.rs
@@ -199,6 +199,7 @@ impl ProjectWorkspace {
                     }
                 }
 
+                let libcore = sysroot.core().and_then(|it| sysroot_crates.get(&it).copied());
                 let libstd = sysroot.std().and_then(|it| sysroot_crates.get(&it).copied());
 
                 let mut pkg_to_lib_crate = FxHashMap::default();
@@ -226,7 +227,7 @@ impl ProjectWorkspace {
                         }
                     }
 
-                    // Set deps to the std and to the lib target of the current package
+                    // Set deps to the core, std and to the lib target of the current package
                     for &from in pkg_crates.get(&pkg).into_iter().flatten() {
                         if let Some(to) = lib_tgt {
                             if to != from {
@@ -240,6 +241,13 @@ impl ProjectWorkspace {
                                 }
                             }
                         }
+                        // core is added as a dependency before std in order to
+                        // mimic rustcs dependency order
+                        if let Some(core) = libcore {
+                            if let Err(_) = crate_graph.add_dep(from, "core".into(), core) {
+                                log::error!("cyclic dependency on core for {}", pkg.name(&cargo))
+                            }
+                        }
                         if let Some(std) = libstd {
                             if let Err(_) = crate_graph.add_dep(from, "std".into(), std) {
                                 log::error!("cyclic dependency on std for {}", pkg.name(&cargo))
diff --git a/crates/ra_project_model/src/sysroot.rs b/crates/ra_project_model/src/sysroot.rs
index 35d6df5cb..3d827809e 100644
--- a/crates/ra_project_model/src/sysroot.rs
+++ b/crates/ra_project_model/src/sysroot.rs
@@ -27,6 +27,10 @@ struct SysrootCrateData {
 }
 
 impl Sysroot {
+    pub fn core(&self) -> Option<SysrootCrate> {
+        self.by_name("core")
+    }
+
     pub fn std(&self) -> Option<SysrootCrate> {
         self.by_name("std")
     }
diff --git a/crates/ra_syntax/src/syntax_error.rs b/crates/ra_syntax/src/syntax_error.rs
index d6eca2ad7..1f60a7aab 100644
--- a/crates/ra_syntax/src/syntax_error.rs
+++ b/crates/ra_syntax/src/syntax_error.rs
@@ -82,6 +82,7 @@ pub enum SyntaxErrorKind {
     InvalidBlockAttr,
     InvalidMatchInnerAttr,
     InvalidTupleIndexFormat,
+    VisibilityNotAllowed,
 }
 
 impl fmt::Display for SyntaxErrorKind {
@@ -99,6 +100,9 @@ impl fmt::Display for SyntaxErrorKind {
             }
             ParseError(msg) => write!(f, "{}", msg.0),
             EscapeError(err) => write!(f, "{}", err),
+            VisibilityNotAllowed => {
+                write!(f, "unnecessary visibility qualifier")
+            }
         }
     }
 }
diff --git a/crates/ra_syntax/src/validation.rs b/crates/ra_syntax/src/validation.rs
index ab4f15908..2d596763e 100644
--- a/crates/ra_syntax/src/validation.rs
+++ b/crates/ra_syntax/src/validation.rs
@@ -6,7 +6,7 @@ use rustc_lexer::unescape;
 
 use crate::{
     ast, match_ast, AstNode, SyntaxError, SyntaxErrorKind,
-    SyntaxKind::{BYTE, BYTE_STRING, CHAR, INT_NUMBER, STRING},
+    SyntaxKind::{BYTE, BYTE_STRING, CHAR, CONST_DEF, FN_DEF, INT_NUMBER, STRING, TYPE_ALIAS_DEF},
     SyntaxNode, SyntaxToken, TextUnit, T,
 };
 
@@ -102,6 +102,7 @@ pub(crate) fn validate(root: &SyntaxNode) -> Vec<SyntaxError> {
                 ast::BlockExpr(it) => { block::validate_block_expr(it, &mut errors) },
                 ast::FieldExpr(it) => { validate_numeric_name(it.name_ref(), &mut errors) },
                 ast::RecordField(it) => { validate_numeric_name(it.name_ref(), &mut errors) },
+                ast::Visibility(it) => { validate_visibility(it, &mut errors) },
                 _ => (),
             }
         }
@@ -206,3 +207,23 @@ fn validate_numeric_name(name_ref: Option<ast::NameRef>, errors: &mut Vec<Syntax
         name_ref?.syntax().first_child_or_token()?.into_token().filter(|it| it.kind() == INT_NUMBER)
     }
 }
+
+fn validate_visibility(vis: ast::Visibility, errors: &mut Vec<SyntaxError>) {
+    let parent = match vis.syntax().parent() {
+        Some(it) => it,
+        None => return,
+    };
+    match parent.kind() {
+        FN_DEF | CONST_DEF | TYPE_ALIAS_DEF => (),
+        _ => return,
+    }
+    let impl_block = match parent.parent().and_then(|it| it.parent()).and_then(ast::ImplBlock::cast)
+    {
+        Some(it) => it,
+        None => return,
+    };
+    if impl_block.target_trait().is_some() {
+        errors
+            .push(SyntaxError::new(SyntaxErrorKind::VisibilityNotAllowed, vis.syntax.text_range()))
+    }
+}
diff --git a/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.rs b/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.rs
new file mode 100644
index 000000000..a43e7ef10
--- /dev/null
+++ b/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.rs
@@ -0,0 +1,6 @@
+impl T for () {
+    fn foo() {}
+    pub fn bar() {}
+    pub(crate) type Baz = ();
+    pub(crate) const C: i32 = 92;
+}
diff --git a/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.txt b/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.txt
new file mode 100644
index 000000000..749c8cddb
--- /dev/null
+++ b/crates/ra_syntax/test_data/parser/err/0037_visibility_in_traits.txt
@@ -0,0 +1,99 @@
+SOURCE_FILE@[0; 118)
+  IMPL_BLOCK@[0; 117)
+    IMPL_KW@[0; 4) "impl"
+    WHITESPACE@[4; 5) " "
+    PATH_TYPE@[5; 6)
+      PATH@[5; 6)
+        PATH_SEGMENT@[5; 6)
+          NAME_REF@[5; 6)
+            IDENT@[5; 6) "T"
+    WHITESPACE@[6; 7) " "
+    FOR_KW@[7; 10) "for"
+    WHITESPACE@[10; 11) " "
+    TUPLE_TYPE@[11; 13)
+      L_PAREN@[11; 12) "("
+      R_PAREN@[12; 13) ")"
+    WHITESPACE@[13; 14) " "
+    ITEM_LIST@[14; 117)
+      L_CURLY@[14; 15) "{"
+      WHITESPACE@[15; 20) "\n    "
+      FN_DEF@[20; 31)
+        FN_KW@[20; 22) "fn"
+        WHITESPACE@[22; 23) " "
+        NAME@[23; 26)
+          IDENT@[23; 26) "foo"
+        PARAM_LIST@[26; 28)
+          L_PAREN@[26; 27) "("
+          R_PAREN@[27; 28) ")"
+        WHITESPACE@[28; 29) " "
+        BLOCK_EXPR@[29; 31)
+          BLOCK@[29; 31)
+            L_CURLY@[29; 30) "{"
+            R_CURLY@[30; 31) "}"
+      WHITESPACE@[31; 36) "\n    "
+      FN_DEF@[36; 51)
+        VISIBILITY@[36; 39)
+          PUB_KW@[36; 39) "pub"
+        WHITESPACE@[39; 40) " "
+        FN_KW@[40; 42) "fn"
+        WHITESPACE@[42; 43) " "
+        NAME@[43; 46)
+          IDENT@[43; 46) "bar"
+        PARAM_LIST@[46; 48)
+          L_PAREN@[46; 47) "("
+          R_PAREN@[47; 48) ")"
+        WHITESPACE@[48; 49) " "
+        BLOCK_EXPR@[49; 51)
+          BLOCK@[49; 51)
+            L_CURLY@[49; 50) "{"
+            R_CURLY@[50; 51) "}"
+      WHITESPACE@[51; 56) "\n    "
+      TYPE_ALIAS_DEF@[56; 81)
+        VISIBILITY@[56; 66)
+          PUB_KW@[56; 59) "pub"
+          L_PAREN@[59; 60) "("
+          CRATE_KW@[60; 65) "crate"
+          R_PAREN@[65; 66) ")"
+        WHITESPACE@[66; 67) " "
+        TYPE_KW@[67; 71) "type"
+        WHITESPACE@[71; 72) " "
+        NAME@[72; 75)
+          IDENT@[72; 75) "Baz"
+        WHITESPACE@[75; 76) " "
+        EQ@[76; 77) "="
+        WHITESPACE@[77; 78) " "
+        TUPLE_TYPE@[78; 80)
+          L_PAREN@[78; 79) "("
+          R_PAREN@[79; 80) ")"
+        SEMI@[80; 81) ";"
+      WHITESPACE@[81; 86) "\n    "
+      CONST_DEF@[86; 115)
+        VISIBILITY@[86; 96)
+          PUB_KW@[86; 89) "pub"
+          L_PAREN@[89; 90) "("
+          CRATE_KW@[90; 95) "crate"
+          R_PAREN@[95; 96) ")"
+        WHITESPACE@[96; 97) " "
+        CONST_KW@[97; 102) "const"
+        WHITESPACE@[102; 103) " "
+        NAME@[103; 104)
+          IDENT@[103; 104) "C"
+        COLON@[104; 105) ":"
+        WHITESPACE@[105; 106) " "
+        PATH_TYPE@[106; 109)
+          PATH@[106; 109)
+            PATH_SEGMENT@[106; 109)
+              NAME_REF@[106; 109)
+                IDENT@[106; 109) "i32"
+        WHITESPACE@[109; 110) " "
+        EQ@[110; 111) "="
+        WHITESPACE@[111; 112) " "
+        LITERAL@[112; 114)
+          INT_NUMBER@[112; 114) "92"
+        SEMI@[114; 115) ";"
+      WHITESPACE@[115; 116) "\n"
+      R_CURLY@[116; 117) "}"
+  WHITESPACE@[117; 118) "\n"
+error [36; 39): unnecessary visibility qualifier
+error [56; 66): unnecessary visibility qualifier
+error [86; 96): unnecessary visibility qualifier