Merge #2201

2201: Resolve core types r=matklad a=Matthias247

This adds support for completion and goto definition of
types defined within the "core" crate. The core crate is
added as a dependency to each crate in the project.

The core crate exported it's own prelude. This caused
now all crates to inherit the core crates prelude instead
of the std crates. In order to avoid the problem the
prelude resolution has been changed to overwrite
an already resolved prelude if this was set to a crate
named core - in order to pick a better prelude like std.

Fixes #2199

Co-authored-by: Matthias Einwag <[email protected]>

1 files changed, 62 insertions, 0 deletions

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(