ImportsLocator: use ImportMap for non-local crates

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 +841,49 @@ 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() {
+        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 {}
+",
+        );
+    }
 }

crates/ra_ide_db/src/imports_locator.rs

@@ -1,7 +1,7 @@
 //! This module contains an import search funcionality that is provided to the ra_assists module.
 //! Later, this should be moved away to a separate crate that is accessible from the ra_assists module.
 
-use hir::{MacroDef, ModuleDef, Semantics};
+use hir::{Crate, MacroDef, ModuleDef, Semantics};
 use ra_prof::profile;
 use ra_syntax::{ast, AstNode, SyntaxKind::NAME};
 
@@ -11,44 +11,46 @@ use crate::{
     RootDatabase,
 };
 use either::Either;
+use rustc_hash::FxHashSet;
 
 pub struct ImportsLocator<'a> {
     sema: Semantics<'a, RootDatabase>,
+    krate: Crate,
 }
 
 impl<'a> ImportsLocator<'a> {
-    pub fn new(db: &'a RootDatabase) -> Self {
-        Self { sema: Semantics::new(db) }
+    pub fn new(db: &'a RootDatabase, krate: Crate) -> Self {
+        Self { sema: Semantics::new(db), krate }
     }
 
     pub fn find_imports(&mut self, name_to_import: &str) -> Vec<Either<ModuleDef, MacroDef>> {
         let _p = profile("search_for_imports");
         let db = self.sema.db;
 
-        let project_results = {
+        // Query dependencies first.
+        let mut candidates: FxHashSet<_> =
+            self.krate.query_external_importables(db, name_to_import).collect();
+
+        // Query the local crate using the symbol index.
+        let local_results = {
             let mut query = Query::new(name_to_import.to_string());
             query.exact();
             query.limit(40);
-            symbol_index::world_symbols(db, query)
-        };
-        let lib_results = {
-            let mut query = Query::new(name_to_import.to_string());
-            query.libs();
-            query.exact();
-            query.limit(40);
-            symbol_index::world_symbols(db, query)
+            symbol_index::crate_symbols(db, self.krate.into(), query)
         };
 
-        project_results
-            .into_iter()
-            .chain(lib_results.into_iter())
-            .filter_map(|import_candidate| self.get_name_definition(&import_candidate))
-            .filter_map(|name_definition_to_import| match name_definition_to_import {
-                Definition::ModuleDef(module_def) => Some(Either::Left(module_def)),
-                Definition::Macro(macro_def) => Some(Either::Right(macro_def)),
-                _ => None,
-            })
-            .collect()
+        candidates.extend(
+            local_results
+                .into_iter()
+                .filter_map(|import_candidate| self.get_name_definition(&import_candidate))
+                .filter_map(|name_definition_to_import| match name_definition_to_import {
+                    Definition::ModuleDef(module_def) => Some(Either::Left(module_def)),
+                    Definition::Macro(macro_def) => Some(Either::Right(macro_def)),
+                    _ => None,
+                }),
+        );
+
+        candidates.into_iter().collect()
     }
 
     fn get_name_definition(&mut self, import_candidate: &FileSymbol) -> Option<Definition> {