1 files changed, 101 insertions, 0 deletions

diff --git a/crates/hir_def/src/nameres/tests/incremental.rs b/crates/hir_def/src/nameres/tests/incremental.rs
new file mode 100644
index 000000000..cfbc62cc4
--- /dev/null
+++ b/crates/hir_def/src/nameres/tests/incremental.rs
@@ -0,0 +1,101 @@
+use std::sync::Arc;
+
+use base_db::SourceDatabaseExt;
+
+use super::*;
+
+fn check_def_map_is_not_recomputed(ra_fixture_initial: &str, ra_fixture_change: &str) {
+    let (mut db, pos) = TestDB::with_position(ra_fixture_initial);
+    let krate = db.test_crate();
+    {
+        let events = db.log_executed(|| {
+            db.crate_def_map(krate);
+        });
+        assert!(format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+    db.set_file_text(pos.file_id, Arc::new(ra_fixture_change.to_string()));
+
+    {
+        let events = db.log_executed(|| {
+            db.crate_def_map(krate);
+        });
+        assert!(!format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+}
+
+#[test]
+fn typing_inside_a_function_should_not_invalidate_def_map() {
+    check_def_map_is_not_recomputed(
+        r"
+        //- /lib.rs
+        mod foo;<|>
+
+        use crate::foo::bar::Baz;
+
+        enum E { A, B }
+        use E::*;
+
+        fn foo() -> i32 {
+            1 + 1
+        }
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+        r"
+        mod foo;
+
+        use crate::foo::bar::Baz;
+
+        enum E { A, B }
+        use E::*;
+
+        fn foo() -> i32 { 92 }
+        ",
+    );
+}
+
+#[test]
+fn typing_inside_a_macro_should_not_invalidate_def_map() {
+    let (mut db, pos) = TestDB::with_position(
+        r"
+        //- /lib.rs
+        macro_rules! m {
+            ($ident:ident) => {
+                fn f() {
+                    $ident + $ident;
+                };
+            }
+        }
+        mod foo;
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        <|>
+        m!(X);
+        ",
+    );
+    let krate = db.test_crate();
+    {
+        let events = db.log_executed(|| {
+            let crate_def_map = db.crate_def_map(krate);
+            let (_, module_data) = crate_def_map.modules.iter().last().unwrap();
+            assert_eq!(module_data.scope.resolutions().count(), 1);
+        });
+        assert!(format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+    db.set_file_text(pos.file_id, Arc::new("m!(Y);".to_string()));
+
+    {
+        let events = db.log_executed(|| {
+            let crate_def_map = db.crate_def_map(krate);
+            let (_, module_data) = crate_def_map.modules.iter().last().unwrap();
+            assert_eq!(module_data.scope.resolutions().count(), 1);
+        });
+        assert!(!format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+}