1 files changed, 64 insertions, 0 deletions

diff --git a/crates/ide_db/src/imports_locator.rs b/crates/ide_db/src/imports_locator.rs
new file mode 100644
index 000000000..ed67e3553
--- /dev/null
+++ b/crates/ide_db/src/imports_locator.rs
@@ -0,0 +1,64 @@
+//! This module contains an import search funcionality that is provided to the assists module.
+//! Later, this should be moved away to a separate crate that is accessible from the assists module.
+
+use hir::{Crate, MacroDef, ModuleDef, Semantics};
+use syntax::{ast, AstNode, SyntaxKind::NAME};
+
+use crate::{
+    defs::{classify_name, Definition},
+    symbol_index::{self, FileSymbol, Query},
+    RootDatabase,
+};
+use either::Either;
+use rustc_hash::FxHashSet;
+
+pub fn find_imports<'a>(
+    sema: &Semantics<'a, RootDatabase>,
+    krate: Crate,
+    name_to_import: &str,
+) -> Vec<Either<ModuleDef, MacroDef>> {
+    let _p = profile::span("search_for_imports");
+    let db = sema.db;
+
+    // Query dependencies first.
+    let mut candidates: FxHashSet<_> =
+        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::crate_symbols(db, krate.into(), query)
+    };
+
+    candidates.extend(
+        local_results
+            .into_iter()
+            .filter_map(|import_candidate| get_name_definition(sema, &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<'a>(
+    sema: &Semantics<'a, RootDatabase>,
+    import_candidate: &FileSymbol,
+) -> Option<Definition> {
+    let _p = profile::span("get_name_definition");
+    let file_id = import_candidate.file_id;
+
+    let candidate_node = import_candidate.ptr.to_node(sema.parse(file_id).syntax());
+    let candidate_name_node = if candidate_node.kind() != NAME {
+        candidate_node.children().find(|it| it.kind() == NAME)?
+    } else {
+        candidate_node
+    };
+    let name = ast::Name::cast(candidate_name_node)?;
+    classify_name(sema, &name)?.into_definition(sema.db)
+}