Merge #4819

4819: Add an FST index to `ImportMap` and use it to speed up auto import r=matklad a=jonas-schievink

For the importing crate, we still use the symbol index, but I've modified it to only look at files that comprise that crate (instead of the whole workspace).

Oh, and since now the symbol query limit is respected correctly, it's possible that some results from the local crate now disappear if there are many matches.

Fixes https://github.com/rust-analyzer/rust-analyzer/issues/4763

Co-authored-by: Jonas Schievink <[email protected]>

1 files changed, 102 insertions, 1 deletions

diff --git a/crates/ra_assists/src/handlers/auto_import.rs b/crates/ra_assists/src/handlers/auto_import.rs
index edf96d50e..5092bf336 100644
--- a/crates/ra_assists/src/handlers/auto_import.rs
+++ b/crates/ra_assists/src/handlers/auto_import.rs
@@ -130,7 +130,7 @@ impl AutoImportAssets {
     fn search_for_imports(&self, db: &RootDatabase) -> BTreeSet<ModPath> {
         let _p = profile("auto_import::search_for_imports");
         let current_crate = self.module_with_name_to_import.krate();
-        ImportsLocator::new(db)
+        ImportsLocator::new(db, current_crate)
             .find_imports(&self.get_search_query())
             .into_iter()
             .filter_map(|candidate| match &self.import_candidate {
@@ -841,4 +841,105 @@ fn main() {
             ",
         )
     }
+
+    #[test]
+    fn dep_import() {
+        check_assist(
+            auto_import,
+            r"
+                    //- /lib.rs crate:dep
+                    pub struct Struct;
+
+                    //- /main.rs crate:main deps:dep
+                    fn main() {
+                        Struct<|>
+                    }",
+            r"use dep::Struct;
+
+fn main() {
+    Struct
+}
+",
+        );
+    }
+
+    #[test]
+    fn whole_segment() {
+        // Tests that only imports whose last segment matches the identifier get suggested.
+        check_assist(
+            auto_import,
+            r"
+                    //- /lib.rs crate:dep
+                    pub mod fmt {
+                        pub trait Display {}
+                    }
+
+                    pub fn panic_fmt() {}
+
+                    //- /main.rs crate:main deps:dep
+                    struct S;
+
+                    impl f<|>mt::Display for S {}",
+            r"use dep::fmt;
+
+struct S;
+impl fmt::Display for S {}
+",
+        );
+    }
+
+    #[test]
+    fn macro_generated() {
+        // Tests that macro-generated items are suggested from external crates.
+        check_assist(
+            auto_import,
+            r"
+                    //- /lib.rs crate:dep
+
+                    macro_rules! mac {
+                        () => {
+                            pub struct Cheese;
+                        };
+                    }
+
+                    mac!();
+
+                    //- /main.rs crate:main deps:dep
+
+                    fn main() {
+                        Cheese<|>;
+                    }",
+            r"use dep::Cheese;
+
+fn main() {
+    Cheese;
+}
+",
+        );
+    }
+
+    #[test]
+    fn casing() {
+        // Tests that differently cased names don't interfere and we only suggest the matching one.
+        check_assist(
+            auto_import,
+            r"
+                    //- /lib.rs crate:dep
+
+                    pub struct FMT;
+                    pub struct fmt;
+
+                    //- /main.rs crate:main deps:dep
+
+                    fn main() {
+                        FMT<|>;
+                    }",
+            r"use dep::FMT;
+
+fn main() {
+    FMT;
+}
+",
+        );
+    }
 }