9 files changed, 2219 insertions, 1 deletions

diff --git a/crates/ra_hir_def/Cargo.toml b/crates/ra_hir_def/Cargo.toml
index 746c907e8..15055db64 100644
--- a/crates/ra_hir_def/Cargo.toml
+++ b/crates/ra_hir_def/Cargo.toml
@@ -19,3 +19,7 @@ test_utils = { path = "../test_utils" }
 mbe = { path = "../ra_mbe", package = "ra_mbe" }
 ra_cfg = { path = "../ra_cfg" }
 tt = { path = "../ra_tt", package = "ra_tt" }
+
+[dev-dependencies]
+insta = "0.12.0"
+
diff --git a/crates/ra_hir_def/src/nameres.rs b/crates/ra_hir_def/src/nameres.rs
index db59344aa..b3640da3d 100644
--- a/crates/ra_hir_def/src/nameres.rs
+++ b/crates/ra_hir_def/src/nameres.rs
@@ -6,6 +6,9 @@ pub mod per_ns;
 pub mod collector;
 pub mod mod_resolution;
 
+#[cfg(test)]
+mod tests;
+
 use std::sync::Arc;
 
 use hir_expand::{diagnostics::DiagnosticSink, name::Name, MacroDefId};
diff --git a/crates/ra_hir_def/src/nameres/tests.rs b/crates/ra_hir_def/src/nameres/tests.rs
new file mode 100644
index 000000000..f9a8edd43
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests.rs
@@ -0,0 +1,522 @@
+mod globs;
+mod incremental;
+mod macros;
+mod mod_resolution;
+mod primitives;
+
+use std::sync::Arc;
+
+use insta::assert_snapshot;
+use ra_db::{fixture::WithFixture, SourceDatabase};
+// use test_utils::covers;
+
+use crate::{db::DefDatabase2, nameres::*, test_db::TestDB, CrateModuleId};
+
+fn def_map(fixtute: &str) -> String {
+    let dm = compute_crate_def_map(fixtute);
+    render_crate_def_map(&dm)
+}
+
+fn compute_crate_def_map(fixture: &str) -> Arc<CrateDefMap> {
+    let db = TestDB::with_files(fixture);
+    let krate = db.crate_graph().iter().next().unwrap();
+    db.crate_def_map(krate)
+}
+
+fn render_crate_def_map(map: &CrateDefMap) -> String {
+    let mut buf = String::new();
+    go(&mut buf, map, "\ncrate", map.root());
+    return buf.trim().to_string();
+
+    fn go(buf: &mut String, map: &CrateDefMap, path: &str, module: CrateModuleId) {
+        *buf += path;
+        *buf += "\n";
+
+        let mut entries = map.modules[module]
+            .scope
+            .items
+            .iter()
+            .map(|(name, res)| (name, res.def))
+            .collect::<Vec<_>>();
+        entries.sort_by_key(|(name, _)| *name);
+
+        for (name, res) in entries {
+            *buf += &format!("{}:", name);
+
+            if res.types.is_some() {
+                *buf += " t";
+            }
+            if res.values.is_some() {
+                *buf += " v";
+            }
+            if res.macros.is_some() {
+                *buf += " m";
+            }
+            if res.is_none() {
+                *buf += " _";
+            }
+
+            *buf += "\n";
+        }
+
+        for (name, child) in map.modules[module].children.iter() {
+            let path = path.to_string() + &format!("::{}", name);
+            go(buf, map, &path, *child);
+        }
+    }
+}
+
+#[test]
+fn crate_def_map_smoke_test() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        struct S;
+        use crate::foo::bar::E;
+        use self::E::V;
+
+        //- /foo/mod.rs
+        pub mod bar;
+        fn f() {}
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        enum E { V }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮E: t
+        ⋮S: t v
+        ⋮V: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮f: v
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+        ⋮E: t
+    "###)
+}
+
+#[test]
+fn bogus_paths() {
+    // covers!(bogus_paths);
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        struct S;
+        use self;
+
+        //- /foo/mod.rs
+        use super;
+        use crate;
+
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮S: t v
+   ⋮foo: t
+   ⋮
+   ⋮crate::foo
+    "###
+    )
+}
+
+#[test]
+fn use_as() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+
+        use crate::foo::Baz as Foo;
+
+        //- /foo/mod.rs
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map,
+        @r###"
+   ⋮crate
+   ⋮Foo: t v
+   ⋮foo: t
+   ⋮
+   ⋮crate::foo
+   ⋮Baz: t v
+    "###
+    );
+}
+
+#[test]
+fn use_trees() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+
+        use crate::foo::bar::{Baz, Quux};
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        pub enum Quux {};
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+        ⋮Quux: t
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+        ⋮Quux: t
+    "###);
+}
+
+#[test]
+fn re_exports() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+
+        use self::foo::Baz;
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        pub use self::bar::Baz;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn std_prelude() {
+    // covers!(std_prelude);
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:test_crate
+        use Foo::*;
+
+        //- /lib.rs crate:test_crate
+        mod prelude;
+        #[prelude_import]
+        use prelude::*;
+
+        //- /prelude.rs
+        pub enum Foo { Bar, Baz };
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn can_import_enum_variant() {
+    // covers!(can_import_enum_variant);
+    let map = def_map(
+        "
+        //- /lib.rs
+        enum E { V }
+        use self::E::V;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮E: t
+        ⋮V: t v
+    "###
+    );
+}
+
+#[test]
+fn edition_2015_imports() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:other_crate edition:2015
+        mod foo;
+        mod bar;
+
+        //- /bar.rs
+        struct Bar;
+
+        //- /foo.rs
+        use bar::Bar;
+        use other_crate::FromLib;
+
+        //- /lib.rs crate:other_crate edition:2018
+        struct FromLib;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮bar: t
+        ⋮foo: t
+        ⋮
+        ⋮crate::bar
+        ⋮Bar: t v
+        ⋮
+        ⋮crate::foo
+        ⋮Bar: t v
+        ⋮FromLib: t v
+    "###);
+}
+
+#[test]
+fn item_map_using_self() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        use crate::foo::bar::Baz::{self};
+        //- /foo/mod.rs
+        pub mod bar;
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn item_map_across_crates() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:test_crate
+        use test_crate::Baz;
+
+        //- /lib.rs crate:test_crate
+        pub struct Baz;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn extern_crate_rename() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:alloc
+        extern crate alloc as alloc_crate;
+
+        mod alloc;
+        mod sync;
+
+        //- /sync.rs
+        use alloc_crate::Arc;
+
+        //- /lib.rs crate:alloc
+        struct Arc;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮alloc_crate: t
+   ⋮sync: t
+   ⋮
+   ⋮crate::sync
+   ⋮Arc: t v
+    "###);
+}
+
+#[test]
+fn extern_crate_rename_2015_edition() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:alloc edition:2015
+        extern crate alloc as alloc_crate;
+
+        mod alloc;
+        mod sync;
+
+        //- /sync.rs
+        use alloc_crate::Arc;
+
+        //- /lib.rs crate:alloc
+        struct Arc;
+        ",
+    );
+
+    assert_snapshot!(map,
+        @r###"
+   ⋮crate
+   ⋮alloc_crate: t
+   ⋮sync: t
+   ⋮
+   ⋮crate::sync
+   ⋮Arc: t v
+    "###
+    );
+}
+
+#[test]
+fn import_across_source_roots() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:test_crate
+        use test_crate::a::b::C;
+
+        //- root /test_crate/
+
+        //- /test_crate/lib.rs crate:test_crate
+        pub mod a {
+            pub mod b {
+                pub struct C;
+            }
+        }
+
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮C: t v
+    "###);
+}
+
+#[test]
+fn reexport_across_crates() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:test_crate
+        use test_crate::Baz;
+
+        //- /lib.rs crate:test_crate
+        pub use foo::Baz;
+
+        mod foo;
+
+        //- /foo.rs
+        pub struct Baz;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn values_dont_shadow_extern_crates() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        fn foo() {}
+        use foo::Bar;
+
+        //- /foo/lib.rs crate:foo
+        pub struct Bar;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮foo: v
+    "###);
+}
+
+#[test]
+fn cfg_not_test() {
+    let map = def_map(
+        r#"
+        //- /main.rs crate:main deps:std
+        use {Foo, Bar, Baz};
+
+        //- /lib.rs crate:std
+        #[prelude_import]
+        pub use self::prelude::*;
+        mod prelude {
+            #[cfg(test)]
+            pub struct Foo;
+            #[cfg(not(test))]
+            pub struct Bar;
+            #[cfg(all(not(any()), feature = "foo", feature = "bar", opt = "42"))]
+            pub struct Baz;
+        }
+        "#,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮Baz: _
+        ⋮Foo: _
+    "###);
+}
+
+#[test]
+fn cfg_test() {
+    let map = def_map(
+        r#"
+        //- /main.rs crate:main deps:std
+        use {Foo, Bar, Baz};
+
+        //- /lib.rs crate:std cfg:test,feature=foo,feature=bar,opt=42
+        #[prelude_import]
+        pub use self::prelude::*;
+        mod prelude {
+            #[cfg(test)]
+            pub struct Foo;
+            #[cfg(not(test))]
+            pub struct Bar;
+            #[cfg(all(not(any()), feature = "foo", feature = "bar", opt = "42"))]
+            pub struct Baz;
+        }
+        "#,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: _
+        ⋮Baz: t v
+        ⋮Foo: t v
+    "###);
+}
diff --git a/crates/ra_hir_def/src/nameres/tests/globs.rs b/crates/ra_hir_def/src/nameres/tests/globs.rs
new file mode 100644
index 000000000..cf4a2a851
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests/globs.rs
@@ -0,0 +1,114 @@
+use super::*;
+
+#[test]
+fn glob_1() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        use foo::*;
+
+        //- /foo/mod.rs
+        pub mod bar;
+        pub use self::bar::Baz;
+        pub struct Foo;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Baz: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮foo: t
+   ⋮
+   ⋮crate::foo
+   ⋮Baz: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮
+   ⋮crate::foo::bar
+   ⋮Baz: t v
+    "###
+    );
+}
+
+#[test]
+fn glob_2() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        use foo::*;
+
+        //- /foo/mod.rs
+        pub mod bar;
+        pub use self::bar::*;
+        pub struct Foo;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        pub use super::*;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Baz: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮foo: t
+   ⋮
+   ⋮crate::foo
+   ⋮Baz: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮
+   ⋮crate::foo::bar
+   ⋮Baz: t v
+   ⋮Foo: t v
+   ⋮bar: t
+    "###
+    );
+}
+
+#[test]
+fn glob_across_crates() {
+    // covers!(glob_across_crates);
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:test_crate
+        use test_crate::*;
+
+        //- /lib.rs crate:test_crate
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Baz: t v
+    "###
+    );
+}
+
+#[test]
+fn glob_enum() {
+    // covers!(glob_enum);
+    let map = def_map(
+        "
+        //- /lib.rs
+        enum Foo {
+            Bar, Baz
+        }
+        use self::Foo::*;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Bar: t v
+   ⋮Baz: t v
+   ⋮Foo: t
+    "###
+    );
+}
diff --git a/crates/ra_hir_def/src/nameres/tests/incremental.rs b/crates/ra_hir_def/src/nameres/tests/incremental.rs
new file mode 100644
index 000000000..80dcec62f
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests/incremental.rs
@@ -0,0 +1,133 @@
+use std::sync::Arc;
+
+use ra_db::{SourceDatabase, SourceDatabaseExt};
+
+use super::*;
+
+fn check_def_map_is_not_recomputed(initial: &str, file_change: &str) {
+    let (mut db, pos) = TestDB::with_position(initial);
+    let krate = db.crate_graph().iter().next().unwrap();
+    {
+        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(file_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(
+        "
+        //- /lib.rs
+        mod foo;<|>
+
+        use crate::foo::bar::Baz;
+
+        fn foo() -> i32 {
+            1 + 1
+        }
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+        "
+        mod foo;
+
+        use crate::foo::bar::Baz;
+
+        fn foo() -> i32 { 92 }
+        ",
+    );
+}
+
+#[test]
+fn adding_inner_items_should_not_invalidate_def_map() {
+    check_def_map_is_not_recomputed(
+        "
+        //- /lib.rs
+        struct S { a: i32}
+        enum E { A }
+        trait T {
+            fn a() {}
+        }
+        mod foo;<|>
+        impl S {
+            fn a() {}
+        }
+        use crate::foo::bar::Baz;
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+        "
+        struct S { a: i32, b: () }
+        enum E { A, B }
+        trait T {
+            fn a() {}
+            fn b() {}
+        }
+        mod foo;<|>
+        impl S {
+            fn a() {}
+            fn b() {}
+        }
+        use crate::foo::bar::Baz;
+        ",
+    );
+}
+
+#[test]
+fn typing_inside_a_macro_should_not_invalidate_def_map() {
+    let (mut db, pos) = TestDB::with_position(
+        "
+        //- /lib.rs
+        macro_rules! m {
+            ($ident:ident) => {
+                fn f() {
+                    $ident + $ident;
+                };
+            }
+        }
+        mod foo;
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        <|>
+        m!(X);
+        ",
+    );
+    let krate = db.crate_graph().iter().next().unwrap();
+    {
+        let events = db.log_executed(|| {
+            let crate_def_map = db.crate_def_map(krate);
+            let (_, module_data) = crate_def_map.modules.iter().last().unwrap();
+            assert_eq!(module_data.scope.items.len(), 1);
+        });
+        assert!(format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+    db.set_file_text(pos.file_id, Arc::new("m!(Y);".to_string()));
+
+    {
+        let events = db.log_executed(|| {
+            let crate_def_map = db.crate_def_map(krate);
+            let (_, module_data) = crate_def_map.modules.iter().last().unwrap();
+            assert_eq!(module_data.scope.items.len(), 1);
+        });
+        assert!(!format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
+    }
+}
diff --git a/crates/ra_hir_def/src/nameres/tests/macros.rs b/crates/ra_hir_def/src/nameres/tests/macros.rs
new file mode 100644
index 000000000..9bb3895ad
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests/macros.rs
@@ -0,0 +1,602 @@
+use super::*;
+
+#[test]
+fn macro_rules_are_globally_visible() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        macro_rules! structs {
+            ($($i:ident),*) => {
+                $(struct $i { field: u32 } )*
+            }
+        }
+        structs!(Foo);
+        mod nested;
+
+        //- /nested.rs
+        structs!(Bar, Baz);
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Foo: t v
+   ⋮nested: t
+   ⋮
+   ⋮crate::nested
+   ⋮Bar: t v
+   ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn macro_rules_can_define_modules() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        macro_rules! m {
+            ($name:ident) => { mod $name;  }
+        }
+        m!(n1);
+
+        mod m {
+            m!(n3)
+        }
+
+        //- /n1.rs
+        m!(n2)
+        //- /n1/n2.rs
+        struct X;
+        //- /m/n3.rs
+        struct Y;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+    crate
+    m: t
+    n1: t
+    
+    crate::m
+    n3: t
+    
+    crate::m::n3
+    Y: t v
+    
+    crate::n1
+    n2: t
+    
+    crate::n1::n2
+    X: t v
+    "###);
+}
+
+#[test]
+fn macro_rules_from_other_crates_are_visible() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        foo::structs!(Foo, Bar)
+        mod bar;
+
+        //- /bar.rs
+        use crate::*;
+
+        //- /lib.rs crate:foo
+        #[macro_export]
+        macro_rules! structs {
+            ($($i:ident),*) => {
+                $(struct $i { field: u32 } )*
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮
+   ⋮crate::bar
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮bar: t
+    "###);
+}
+
+#[test]
+fn macro_rules_export_with_local_inner_macros_are_visible() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        foo::structs!(Foo, Bar)
+        mod bar;
+
+        //- /bar.rs
+        use crate::*;
+
+        //- /lib.rs crate:foo
+        #[macro_export(local_inner_macros)]
+        macro_rules! structs {
+            ($($i:ident),*) => {
+                $(struct $i { field: u32 } )*
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮
+   ⋮crate::bar
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮bar: t
+    "###);
+}
+
+#[test]
+fn unexpanded_macro_should_expand_by_fixedpoint_loop() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        macro_rules! baz {
+            () => {
+                use foo::bar;
+            }
+        }
+
+        foo!();
+        bar!();
+        baz!();
+
+        //- /lib.rs crate:foo
+        #[macro_export]
+        macro_rules! foo {
+            () => {
+                struct Foo { field: u32 }
+            }
+        }
+        #[macro_export]
+        macro_rules! bar {
+            () => {
+                use foo::foo;
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Foo: t v
+   ⋮bar: m
+   ⋮foo: m
+    "###);
+}
+
+#[test]
+fn macro_rules_from_other_crates_are_visible_with_macro_use() {
+    // covers!(macro_rules_from_other_crates_are_visible_with_macro_use);
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        structs!(Foo);
+        structs_priv!(Bar);
+        structs_not_exported!(MacroNotResolved1);
+        crate::structs!(MacroNotResolved2);
+
+        mod bar;
+
+        #[macro_use]
+        extern crate foo;
+
+        //- /bar.rs
+        structs!(Baz);
+        crate::structs!(MacroNotResolved3);
+
+        //- /lib.rs crate:foo
+        #[macro_export]
+        macro_rules! structs {
+            ($i:ident) => { struct $i; }
+        }
+
+        macro_rules! structs_not_exported {
+            ($i:ident) => { struct $i; }
+        }
+
+        mod priv_mod {
+            #[macro_export]
+            macro_rules! structs_priv {
+                ($i:ident) => { struct $i; }
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮bar: t
+   ⋮foo: t
+   ⋮
+   ⋮crate::bar
+   ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn prelude_is_macro_use() {
+    // covers!(prelude_is_macro_use);
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        structs!(Foo);
+        structs_priv!(Bar);
+        structs_outside!(Out);
+        crate::structs!(MacroNotResolved2);
+
+        mod bar;
+
+        //- /bar.rs
+        structs!(Baz);
+        crate::structs!(MacroNotResolved3);
+
+        //- /lib.rs crate:foo
+        #[prelude_import]
+        use self::prelude::*;
+
+        mod prelude {
+            #[macro_export]
+            macro_rules! structs {
+                ($i:ident) => { struct $i; }
+            }
+
+            mod priv_mod {
+                #[macro_export]
+                macro_rules! structs_priv {
+                    ($i:ident) => { struct $i; }
+                }
+            }
+        }
+
+        #[macro_export]
+        macro_rules! structs_outside {
+            ($i:ident) => { struct $i; }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Bar: t v
+   ⋮Foo: t v
+   ⋮Out: t v
+   ⋮bar: t
+   ⋮
+   ⋮crate::bar
+   ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn prelude_cycle() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        #[prelude_import]
+        use self::prelude::*;
+
+        declare_mod!();
+
+        mod prelude {
+            macro_rules! declare_mod {
+                () => (mod foo {})
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮prelude: t
+        ⋮
+        ⋮crate::prelude
+    "###);
+}
+
+#[test]
+fn plain_macros_are_legacy_textual_scoped() {
+    let map = def_map(
+        r#"
+        //- /main.rs
+        mod m1;
+        bar!(NotFoundNotMacroUse);
+
+        mod m2 {
+            foo!(NotFoundBeforeInside2);
+        }
+
+        macro_rules! foo {
+            ($x:ident) => { struct $x; }
+        }
+        foo!(Ok);
+
+        mod m3;
+        foo!(OkShadowStop);
+        bar!(NotFoundMacroUseStop);
+
+        #[macro_use]
+        mod m5 {
+            #[macro_use]
+            mod m6 {
+                macro_rules! foo {
+                    ($x:ident) => { fn $x() {} }
+                }
+            }
+        }
+        foo!(ok_double_macro_use_shadow);
+
+        baz!(NotFoundBefore);
+        #[macro_use]
+        mod m7 {
+            macro_rules! baz {
+                ($x:ident) => { struct $x; }
+            }
+        }
+        baz!(OkAfter);
+
+        //- /m1.rs
+        foo!(NotFoundBeforeInside1);
+        macro_rules! bar {
+            ($x:ident) => { struct $x; }
+        }
+
+        //- /m3/mod.rs
+        foo!(OkAfterInside);
+        macro_rules! foo {
+            ($x:ident) => { fn $x() {} }
+        }
+        foo!(ok_shadow);
+
+        #[macro_use]
+        mod m4;
+        bar!(OkMacroUse);
+
+        //- /m3/m4.rs
+        foo!(ok_shadow_deep);
+        macro_rules! bar {
+            ($x:ident) => { struct $x; }
+        }
+        "#,
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮Ok: t v
+   ⋮OkAfter: t v
+   ⋮OkShadowStop: t v
+   ⋮m1: t
+   ⋮m2: t
+   ⋮m3: t
+   ⋮m5: t
+   ⋮m7: t
+   ⋮ok_double_macro_use_shadow: v
+   ⋮
+   ⋮crate::m7
+   ⋮
+   ⋮crate::m1
+   ⋮
+   ⋮crate::m5
+   ⋮m6: t
+   ⋮
+   ⋮crate::m5::m6
+   ⋮
+   ⋮crate::m2
+   ⋮
+   ⋮crate::m3
+   ⋮OkAfterInside: t v
+   ⋮OkMacroUse: t v
+   ⋮m4: t
+   ⋮ok_shadow: v
+   ⋮
+   ⋮crate::m3::m4
+   ⋮ok_shadow_deep: v
+    "###);
+}
+
+#[test]
+fn type_value_macro_live_in_different_scopes() {
+    let map = def_map(
+        "
+        //- /main.rs
+        #[macro_export]
+        macro_rules! foo {
+            ($x:ident) => { type $x = (); }
+        }
+
+        foo!(foo);
+        use foo as bar;
+
+        use self::foo as baz;
+        fn baz() {}
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮bar: t m
+        ⋮baz: t v m
+        ⋮foo: t m
+    "###);
+}
+
+#[test]
+fn macro_use_can_be_aliased() {
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        #[macro_use]
+        extern crate foo;
+
+        foo!(Direct);
+        bar!(Alias);
+
+        //- /lib.rs crate:foo
+        use crate::foo as bar;
+
+        mod m {
+            #[macro_export]
+            macro_rules! foo {
+                ($x:ident) => { struct $x; }
+            }
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Alias: t v
+        ⋮Direct: t v
+        ⋮foo: t
+    "###);
+}
+
+#[test]
+fn path_qualified_macros() {
+    let map = def_map(
+        "
+        //- /main.rs
+        macro_rules! foo {
+            ($x:ident) => { struct $x; }
+        }
+
+        crate::foo!(NotResolved);
+
+        crate::bar!(OkCrate);
+        bar!(OkPlain);
+        alias1!(NotHere);
+        m::alias1!(OkAliasPlain);
+        m::alias2!(OkAliasSuper);
+        m::alias3!(OkAliasCrate);
+        not_found!(NotFound);
+
+        mod m {
+            #[macro_export]
+            macro_rules! bar {
+                ($x:ident) => { struct $x; }
+            }
+
+            pub use bar as alias1;
+            pub use super::bar as alias2;
+            pub use crate::bar as alias3;
+            pub use self::bar as not_found;
+        }
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮OkAliasCrate: t v
+        ⋮OkAliasPlain: t v
+        ⋮OkAliasSuper: t v
+        ⋮OkCrate: t v
+        ⋮OkPlain: t v
+        ⋮bar: m
+        ⋮m: t
+        ⋮
+        ⋮crate::m
+        ⋮alias1: m
+        ⋮alias2: m
+        ⋮alias3: m
+        ⋮not_found: _
+    "###);
+}
+
+#[test]
+fn macro_dollar_crate_is_correct_in_item() {
+    // covers!(macro_dollar_crate_self);
+    // covers!(macro_dollar_crate_other);
+    let map = def_map(
+        "
+        //- /main.rs crate:main deps:foo
+        #[macro_use]
+        extern crate foo;
+
+        #[macro_use]
+        mod m {
+            macro_rules! current {
+                () => {
+                    use $crate::Foo as FooSelf;
+                }
+            }
+        }
+
+        struct Foo;
+
+        current!();
+        not_current1!();
+        foo::not_current2!();
+
+        //- /lib.rs crate:foo
+        mod m {
+            #[macro_export]
+            macro_rules! not_current1 {
+                () => {
+                    use $crate::Bar;
+                }
+            }
+        }
+
+        #[macro_export]
+        macro_rules! not_current2 {
+            () => {
+                use $crate::Baz;
+            }
+        }
+
+        struct Bar;
+        struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮Baz: t v
+        ⋮Foo: t v
+        ⋮FooSelf: t v
+        ⋮foo: t
+        ⋮m: t
+        ⋮
+        ⋮crate::m
+    "###);
+}
+
+#[test]
+fn macro_dollar_crate_is_correct_in_indirect_deps() {
+    // covers!(macro_dollar_crate_other);
+    // From std
+    let map = def_map(
+        r#"
+        //- /main.rs crate:main deps:std
+        foo!();
+
+        //- /std.rs crate:std deps:core
+        #[prelude_import]
+        use self::prelude::*;
+
+        pub use core::foo;
+
+        mod prelude {}
+
+        #[macro_use]
+        mod std_macros;
+
+        //- /core.rs crate:core
+        #[macro_export]
+        macro_rules! foo {
+            () => {
+                use $crate::bar;
+            }
+        }
+
+        pub struct bar;
+        "#,
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮bar: t v
+    "###);
+}
diff --git a/crates/ra_hir_def/src/nameres/tests/mod_resolution.rs b/crates/ra_hir_def/src/nameres/tests/mod_resolution.rs
new file mode 100644
index 000000000..8d804a63e
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests/mod_resolution.rs
@@ -0,0 +1,782 @@
+use super::*;
+
+#[test]
+fn name_res_works_for_broken_modules() {
+    // covers!(name_res_works_for_broken_modules);
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo // no `;`, no body
+
+        use self::foo::Baz;
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        pub use self::bar::Baz;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: _
+    "###);
+}
+
+#[test]
+fn nested_module_resolution() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod n1;
+
+        //- /n1.rs
+        mod n2;
+
+        //- /n1/n2.rs
+        struct X;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮n1: t
+        ⋮
+        ⋮crate::n1
+        ⋮n2: t
+        ⋮
+        ⋮crate::n1::n2
+        ⋮X: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_works_for_non_standard_filenames() {
+    let map = def_map(
+        "
+        //- /my_library.rs crate:my_library
+        mod foo;
+        use self::foo::Bar;
+
+        //- /foo/mod.rs
+        pub struct Bar;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Bar: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_works_for_raw_modules() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod r#async;
+        use self::r#async::Bar;
+
+        //- /async.rs
+        pub struct Bar;
+        ",
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮async: t
+        ⋮
+        ⋮crate::async
+        ⋮Bar: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_path() {
+    let map = def_map(
+        r###"
+        //- /lib.rs
+        #[path = "bar/baz/foo.rs"]
+        mod foo;
+        use self::foo::Bar;
+
+        //- /bar/baz/foo.rs
+        pub struct Bar;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Bar: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Bar: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_module_with_path_in_mod_rs() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo/mod.rs
+        #[path = "baz.rs"]
+        pub mod bar;
+
+        use self::bar::Baz;
+
+        //- /foo/baz.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_module_with_path_non_crate_root() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo.rs
+        #[path = "baz.rs"]
+        pub mod bar;
+
+        use self::bar::Baz;
+
+        //- /baz.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_module_decl_path_super() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "bar/baz/module.rs"]
+        mod foo;
+        pub struct Baz;
+
+        //- /bar/baz/module.rs
+        use super::Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_explicit_path_mod_rs() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "module/mod.rs"]
+        mod foo;
+
+        //- /module/mod.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_relative_path() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo.rs
+        #[path = "./sub.rs"]
+        pub mod foo_bar;
+
+        //- /sub.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮foo_bar: t
+        ⋮
+        ⋮crate::foo::foo_bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_relative_path_2() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo/mod.rs
+        #[path="../sub.rs"]
+        pub mod foo_bar;
+
+        //- /sub.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮foo_bar: t
+        ⋮
+        ⋮crate::foo::foo_bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_explicit_path_mod_rs_2() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "module/bar/mod.rs"]
+        mod foo;
+
+        //- /module/bar/mod.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_explicit_path_mod_rs_with_win_separator() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "module\bar\mod.rs"]
+        mod foo;
+
+        //- /module/bar/mod.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_with_path_attribute() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "models"]
+        mod foo {
+            mod bar;
+        }
+
+        //- /models/bar.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo {
+            mod bar;
+        }
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_2_with_path_attribute() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "models/db"]
+        mod foo {
+            mod bar;
+        }
+
+        //- /models/db/bar.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_3() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "models/db"]
+        mod foo {
+            #[path = "users.rs"]
+            mod bar;
+        }
+
+        //- /models/db/users.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_empty_path() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = ""]
+        mod foo {
+            #[path = "users.rs"]
+            mod bar;
+        }
+
+        //- /users.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_empty_path() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = ""] // Should try to read `/` (a directory)
+        mod foo;
+
+        //- /foo.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_relative_path() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path = "./models"]
+        mod foo {
+            mod bar;
+        }
+
+        //- /models/bar.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_in_crate_root() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo {
+            #[path = "baz.rs"]
+            mod bar;
+        }
+        use self::foo::bar::Baz;
+
+        //- /foo/baz.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮Baz: t v
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_in_mod_rs() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo/mod.rs
+        mod bar {
+            #[path = "qwe.rs"]
+            pub mod baz;
+        }
+        use self::bar::baz::Baz;
+
+        //- /foo/bar/qwe.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮baz: t
+        ⋮
+        ⋮crate::foo::bar::baz
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_in_non_crate_root() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo.rs
+        mod bar {
+            #[path = "qwe.rs"]
+            pub mod baz;
+        }
+        use self::bar::baz::Baz;
+
+        //- /foo/bar/qwe.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮baz: t
+        ⋮
+        ⋮crate::foo::bar::baz
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn module_resolution_decl_inside_inline_module_in_non_crate_root_2() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        mod foo;
+
+        //- /foo.rs
+        #[path = "bar"]
+        mod bar {
+            pub mod baz;
+        }
+        use self::bar::baz::Baz;
+
+        //- /bar/baz.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮foo: t
+        ⋮
+        ⋮crate::foo
+        ⋮Baz: t v
+        ⋮bar: t
+        ⋮
+        ⋮crate::foo::bar
+        ⋮baz: t
+        ⋮
+        ⋮crate::foo::bar::baz
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn unresolved_module_diagnostics() {
+    let db = TestDB::with_files(
+        r"
+        //- /lib.rs
+        mod foo;
+        mod bar;
+        mod baz {}
+        //- /foo.rs
+        ",
+    );
+    let krate = db.crate_graph().iter().next().unwrap();
+
+    let crate_def_map = db.crate_def_map(krate);
+
+    insta::assert_debug_snapshot!(
+        crate_def_map.diagnostics,
+        @r###"
+    [
+        UnresolvedModule {
+            module: CrateModuleId(
+                0,
+            ),
+            declaration: AstId {
+                file_id: HirFileId(
+                    FileId(
+                        FileId(
+                            0,
+                        ),
+                    ),
+                ),
+                file_ast_id: FileAstId {
+                    raw: ErasedFileAstId(
+                        1,
+                    ),
+                    _ty: PhantomData,
+                },
+            },
+            candidate: "bar.rs",
+        },
+    ]
+    "###
+    );
+}
+
+#[test]
+fn module_resolution_decl_inside_module_in_non_crate_root_2() {
+    let map = def_map(
+        r###"
+        //- /main.rs
+        #[path="module/m2.rs"]
+        mod module;
+
+        //- /module/m2.rs
+        pub mod submod;
+
+        //- /module/submod.rs
+        pub struct Baz;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+        ⋮crate
+        ⋮module: t
+        ⋮
+        ⋮crate::module
+        ⋮submod: t
+        ⋮
+        ⋮crate::module::submod
+        ⋮Baz: t v
+    "###);
+}
+
+#[test]
+fn nested_out_of_line_module() {
+    let map = def_map(
+        r###"
+        //- /lib.rs
+        mod a {
+            mod b {
+                mod c;
+            }
+        }
+
+        //- /a/b/c.rs
+        struct X;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+    crate
+    a: t
+    
+    crate::a
+    b: t
+    
+    crate::a::b
+    c: t
+    
+    crate::a::b::c
+    X: t v
+    "###);
+}
+
+#[test]
+fn nested_out_of_line_module_with_path() {
+    let map = def_map(
+        r###"
+        //- /lib.rs
+        mod a {
+            #[path = "d/e"]
+            mod b {
+                mod c;
+            }
+        }
+
+        //- /a/d/e/c.rs
+        struct X;
+        "###,
+    );
+
+    assert_snapshot!(map, @r###"
+    crate
+    a: t
+    
+    crate::a
+    b: t
+    
+    crate::a::b
+    c: t
+    
+    crate::a::b::c
+    X: t v
+    "###);
+}
diff --git a/crates/ra_hir_def/src/nameres/tests/primitives.rs b/crates/ra_hir_def/src/nameres/tests/primitives.rs
new file mode 100644
index 000000000..0e2708658
--- /dev/null
+++ b/crates/ra_hir_def/src/nameres/tests/primitives.rs
@@ -0,0 +1,24 @@
+use super::*;
+
+#[test]
+fn primitive_reexport() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        use foo::int;
+
+        //- /foo.rs
+        pub use i32 as int;
+        ",
+    );
+    assert_snapshot!(map, @r###"
+   ⋮crate
+   ⋮foo: t
+   ⋮int: t
+   ⋮
+   ⋮crate::foo
+   ⋮int: t
+    "###
+    );
+}
diff --git a/crates/ra_hir_def/src/test_db.rs b/crates/ra_hir_def/src/test_db.rs
index 67714c68e..05018f8e4 100644
--- a/crates/ra_hir_def/src/test_db.rs
+++ b/crates/ra_hir_def/src/test_db.rs
@@ -1,4 +1,7 @@
-use std::{panic, sync::Arc};
+use std::{
+    panic,
+    sync::{Arc, Mutex},
+};
 
 use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate};
 use relative_path::RelativePath;
@@ -13,12 +16,20 @@ use relative_path::RelativePath;
 #[derive(Debug, Default)]
 pub struct TestDB {
     runtime: salsa::Runtime<TestDB>,
+    events: Mutex<Option<Vec<salsa::Event<TestDB>>>>,
 }
 
 impl salsa::Database for TestDB {
     fn salsa_runtime(&self) -> &salsa::Runtime<Self> {
         &self.runtime
     }
+
+    fn salsa_event(&self, event: impl Fn() -> salsa::Event<TestDB>) {
+        let mut events = self.events.lock().unwrap();
+        if let Some(events) = &mut *events {
+            events.push(event());
+        }
+    }
 }
 
 impl panic::RefUnwindSafe for TestDB {}
@@ -38,3 +49,26 @@ impl FileLoader for TestDB {
         FileLoaderDelegate(self).relevant_crates(file_id)
     }
 }
+
+impl TestDB {
+    pub fn log(&self, f: impl FnOnce()) -> Vec<salsa::Event<TestDB>> {
+        *self.events.lock().unwrap() = Some(Vec::new());
+        f();
+        self.events.lock().unwrap().take().unwrap()
+    }
+
+    pub fn log_executed(&self, f: impl FnOnce()) -> Vec<String> {
+        let events = self.log(f);
+        events
+            .into_iter()
+            .filter_map(|e| match e.kind {
+                // This pretty horrible, but `Debug` is the only way to inspect
+                // QueryDescriptor at the moment.
+                salsa::EventKind::WillExecute { database_key } => {
+                    Some(format!("{:?}", database_key))
+                }
+                _ => None,
+            })
+            .collect()
+    }
+}