4 files changed, 164 insertions, 119 deletions

diff --git a/crates/ide_db/src/helpers/insert_use/tests.rs b/crates/ide_db/src/helpers/insert_use/tests.rs
index 048c213e2..248227d29 100644
--- a/crates/ide_db/src/helpers/insert_use/tests.rs
+++ b/crates/ide_db/src/helpers/insert_use/tests.rs
@@ -44,7 +44,7 @@ fn insert_not_group_empty() {
 
 #[test]
 fn insert_existing() {
-    check_full("std::fs", "use std::fs;", "use std::fs;")
+    check_crate("std::fs", "use std::fs;", "use std::fs;")
 }
 
 #[test]
@@ -249,7 +249,7 @@ use self::fmt;",
 
 #[test]
 fn insert_no_imports() {
-    check_full(
+    check_crate(
         "foo::bar",
         "fn main() {}",
         r"use foo::bar;
@@ -263,7 +263,7 @@ fn insert_empty_file() {
     cov_mark::check!(insert_group_empty_file);
     // empty files will get two trailing newlines
     // this is due to the test case insert_no_imports above
-    check_full(
+    check_crate(
         "foo::bar",
         "",
         r"use foo::bar;
@@ -290,7 +290,7 @@ fn insert_empty_module() {
 #[test]
 fn insert_after_inner_attr() {
     cov_mark::check!(insert_group_empty_inner_attr);
-    check_full(
+    check_crate(
         "foo::bar",
         r"#![allow(unused_imports)]",
         r"#![allow(unused_imports)]
@@ -301,7 +301,7 @@ use foo::bar;",
 
 #[test]
 fn insert_after_inner_attr2() {
-    check_full(
+    check_crate(
         "foo::bar",
         r"#![allow(unused_imports)]
 
@@ -371,12 +371,12 @@ fn main() {}"#,
 
 #[test]
 fn merge_groups() {
-    check_last("std::io", r"use std::fmt;", r"use std::{fmt, io};")
+    check_module("std::io", r"use std::fmt;", r"use std::{fmt, io};")
 }
 
 #[test]
 fn merge_groups_last() {
-    check_last(
+    check_module(
         "std::io",
         r"use std::fmt::{Result, Display};",
         r"use std::fmt::{Result, Display};
@@ -386,12 +386,12 @@ use std::io;",
 
 #[test]
 fn merge_last_into_self() {
-    check_last("foo::bar::baz", r"use foo::bar;", r"use foo::bar::{self, baz};");
+    check_module("foo::bar::baz", r"use foo::bar;", r"use foo::bar::{self, baz};");
 }
 
 #[test]
 fn merge_groups_full() {
-    check_full(
+    check_crate(
         "std::io",
         r"use std::fmt::{Result, Display};",
         r"use std::{fmt::{Result, Display}, io};",
@@ -400,17 +400,21 @@ fn merge_groups_full() {
 
 #[test]
 fn merge_groups_long_full() {
-    check_full("std::foo::bar::Baz", r"use std::foo::bar::Qux;", r"use std::foo::bar::{Baz, Qux};")
+    check_crate("std::foo::bar::Baz", r"use std::foo::bar::Qux;", r"use std::foo::bar::{Baz, Qux};")
 }
 
 #[test]
 fn merge_groups_long_last() {
-    check_last("std::foo::bar::Baz", r"use std::foo::bar::Qux;", r"use std::foo::bar::{Baz, Qux};")
+    check_module(
+        "std::foo::bar::Baz",
+        r"use std::foo::bar::Qux;",
+        r"use std::foo::bar::{Baz, Qux};",
+    )
 }
 
 #[test]
 fn merge_groups_long_full_list() {
-    check_full(
+    check_crate(
         "std::foo::bar::Baz",
         r"use std::foo::bar::{Qux, Quux};",
         r"use std::foo::bar::{Baz, Quux, Qux};",
@@ -419,7 +423,7 @@ fn merge_groups_long_full_list() {
 
 #[test]
 fn merge_groups_long_last_list() {
-    check_last(
+    check_module(
         "std::foo::bar::Baz",
         r"use std::foo::bar::{Qux, Quux};",
         r"use std::foo::bar::{Baz, Quux, Qux};",
@@ -428,7 +432,7 @@ fn merge_groups_long_last_list() {
 
 #[test]
 fn merge_groups_long_full_nested() {
-    check_full(
+    check_crate(
         "std::foo::bar::Baz",
         r"use std::foo::bar::{Qux, quux::{Fez, Fizz}};",
         r"use std::foo::bar::{Baz, Qux, quux::{Fez, Fizz}};",
@@ -437,7 +441,7 @@ fn merge_groups_long_full_nested() {
 
 #[test]
 fn merge_groups_long_last_nested() {
-    check_last(
+    check_module(
         "std::foo::bar::Baz",
         r"use std::foo::bar::{Qux, quux::{Fez, Fizz}};",
         r"use std::foo::bar::Baz;
@@ -447,7 +451,7 @@ use std::foo::bar::{Qux, quux::{Fez, Fizz}};",
 
 #[test]
 fn merge_groups_full_nested_deep() {
-    check_full(
+    check_crate(
         "std::foo::bar::quux::Baz",
         r"use std::foo::bar::{Qux, quux::{Fez, Fizz}};",
         r"use std::foo::bar::{Qux, quux::{Baz, Fez, Fizz}};",
@@ -456,7 +460,7 @@ fn merge_groups_full_nested_deep() {
 
 #[test]
 fn merge_groups_full_nested_long() {
-    check_full(
+    check_crate(
         "std::foo::bar::Baz",
         r"use std::{foo::bar::Qux};",
         r"use std::{foo::bar::{Baz, Qux}};",
@@ -465,7 +469,7 @@ fn merge_groups_full_nested_long() {
 
 #[test]
 fn merge_groups_last_nested_long() {
-    check_full(
+    check_crate(
         "std::foo::bar::Baz",
         r"use std::{foo::bar::Qux};",
         r"use std::{foo::bar::{Baz, Qux}};",
@@ -474,7 +478,7 @@ fn merge_groups_last_nested_long() {
 
 #[test]
 fn merge_groups_skip_pub() {
-    check_full(
+    check_crate(
         "std::io",
         r"pub use std::fmt::{Result, Display};",
         r"pub use std::fmt::{Result, Display};
@@ -484,7 +488,7 @@ use std::io;",
 
 #[test]
 fn merge_groups_skip_pub_crate() {
-    check_full(
+    check_crate(
         "std::io",
         r"pub(crate) use std::fmt::{Result, Display};",
         r"pub(crate) use std::fmt::{Result, Display};
@@ -494,7 +498,7 @@ use std::io;",
 
 #[test]
 fn merge_groups_skip_attributed() {
-    check_full(
+    check_crate(
         "std::io",
         r#"
 #[cfg(feature = "gated")] use std::fmt::{Result, Display};
@@ -509,7 +513,7 @@ use std::io;
 #[test]
 #[ignore] // FIXME: Support this
 fn split_out_merge() {
-    check_last(
+    check_module(
         "std::fmt::Result",
         r"use std::{fmt, io};",
         r"use std::fmt::{self, Result};
@@ -519,29 +523,33 @@ use std::io;",
 
 #[test]
 fn merge_into_module_import() {
-    check_full("std::fmt::Result", r"use std::{fmt, io};", r"use std::{fmt::{self, Result}, io};")
+    check_crate("std::fmt::Result", r"use std::{fmt, io};", r"use std::{fmt::{self, Result}, io};")
 }
 
 #[test]
 fn merge_groups_self() {
-    check_full("std::fmt::Debug", r"use std::fmt;", r"use std::fmt::{self, Debug};")
+    check_crate("std::fmt::Debug", r"use std::fmt;", r"use std::fmt::{self, Debug};")
 }
 
 #[test]
 fn merge_mod_into_glob() {
-    check_full("token::TokenKind", r"use token::TokenKind::*;", r"use token::TokenKind::{*, self};")
+    check_crate(
+        "token::TokenKind",
+        r"use token::TokenKind::*;",
+        r"use token::TokenKind::{*, self};",
+    )
     // FIXME: have it emit `use token::TokenKind::{self, *}`?
 }
 
 #[test]
 fn merge_self_glob() {
-    check_full("self", r"use self::*;", r"use self::{*, self};")
+    check_crate("self", r"use self::*;", r"use self::{*, self};")
     // FIXME: have it emit `use {self, *}`?
 }
 
 #[test]
 fn merge_glob_nested() {
-    check_full(
+    check_crate(
         "foo::bar::quux::Fez",
         r"use foo::bar::{Baz, quux::*};",
         r"use foo::bar::{Baz, quux::{self::*, Fez}};",
@@ -550,7 +558,7 @@ fn merge_glob_nested() {
 
 #[test]
 fn merge_nested_considers_first_segments() {
-    check_full(
+    check_crate(
         "hir_ty::display::write_bounds_like_dyn_trait",
         r"use hir_ty::{autoderef, display::{HirDisplayError, HirFormatter}, method_resolution};",
         r"use hir_ty::{autoderef, display::{HirDisplayError, HirFormatter, write_bounds_like_dyn_trait}, method_resolution};",
@@ -559,7 +567,7 @@ fn merge_nested_considers_first_segments() {
 
 #[test]
 fn skip_merge_last_too_long() {
-    check_last(
+    check_module(
         "foo::bar",
         r"use foo::bar::baz::Qux;",
         r"use foo::bar;
@@ -569,7 +577,7 @@ use foo::bar::baz::Qux;",
 
 #[test]
 fn skip_merge_last_too_long2() {
-    check_last(
+    check_module(
         "foo::bar::baz::Qux",
         r"use foo::bar;",
         r"use foo::bar;
@@ -592,7 +600,7 @@ fn merge_last_fail() {
     check_merge_only_fail(
         r"use foo::bar::{baz::{Qux, Fez}};",
         r"use foo::bar::{baaz::{Quux, Feez}};",
-        MergeBehavior::Last,
+        MergeBehavior::Module,
     );
 }
 
@@ -601,7 +609,7 @@ fn merge_last_fail1() {
     check_merge_only_fail(
         r"use foo::bar::{baz::{Qux, Fez}};",
         r"use foo::bar::baaz::{Quux, Feez};",
-        MergeBehavior::Last,
+        MergeBehavior::Module,
     );
 }
 
@@ -610,7 +618,7 @@ fn merge_last_fail2() {
     check_merge_only_fail(
         r"use foo::bar::baz::{Qux, Fez};",
         r"use foo::bar::{baaz::{Quux, Feez}};",
-        MergeBehavior::Last,
+        MergeBehavior::Module,
     );
 }
 
@@ -619,7 +627,7 @@ fn merge_last_fail3() {
     check_merge_only_fail(
         r"use foo::bar::baz::{Qux, Fez};",
         r"use foo::bar::baaz::{Quux, Feez};",
-        MergeBehavior::Last,
+        MergeBehavior::Module,
     );
 }
 
@@ -648,12 +656,12 @@ fn check(
     assert_eq_text!(ra_fixture_after, &result);
 }
 
-fn check_full(path: &str, ra_fixture_before: &str, ra_fixture_after: &str) {
-    check(path, ra_fixture_before, ra_fixture_after, Some(MergeBehavior::Full), false, true)
+fn check_crate(path: &str, ra_fixture_before: &str, ra_fixture_after: &str) {
+    check(path, ra_fixture_before, ra_fixture_after, Some(MergeBehavior::Crate), false, true)
 }
 
-fn check_last(path: &str, ra_fixture_before: &str, ra_fixture_after: &str) {
-    check(path, ra_fixture_before, ra_fixture_after, Some(MergeBehavior::Last), false, true)
+fn check_module(path: &str, ra_fixture_before: &str, ra_fixture_after: &str) {
+    check(path, ra_fixture_before, ra_fixture_after, Some(MergeBehavior::Module), false, true)
 }
 
 fn check_none(path: &str, ra_fixture_before: &str, ra_fixture_after: &str) {
diff --git a/crates/ide_db/src/helpers/merge_imports.rs b/crates/ide_db/src/helpers/merge_imports.rs
index 3f5bbef7f..af2a51a4d 100644
--- a/crates/ide_db/src/helpers/merge_imports.rs
+++ b/crates/ide_db/src/helpers/merge_imports.rs
@@ -9,19 +9,19 @@ use syntax::ast::{
 /// What type of merges are allowed.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum MergeBehavior {
-    /// Merge everything together creating deeply nested imports.
-    Full,
-    /// Only merge the last import level, doesn't allow import nesting.
-    Last,
+    /// Merge imports from the same crate into a single use statement.
+    Crate,
+    /// Merge imports from the same module into a single use statement.
+    Module,
 }
 
 impl MergeBehavior {
     #[inline]
     fn is_tree_allowed(&self, tree: &ast::UseTree) -> bool {
         match self {
-            MergeBehavior::Full => true,
+            MergeBehavior::Crate => true,
             // only simple single segment paths are allowed
-            MergeBehavior::Last => {
+            MergeBehavior::Module => {
                 tree.use_tree_list().is_none() && tree.path().map(path_len) <= Some(1)
             }
         }
@@ -137,7 +137,7 @@ fn recursive_merge(
                             None,
                             false,
                         );
-                        use_trees.insert(idx, make::glob_use_tree());
+                        use_trees.insert(idx, make::use_tree_glob());
                         continue;
                     }
 
@@ -153,7 +153,7 @@ fn recursive_merge(
                 }
             }
             Err(_)
-                if merge == MergeBehavior::Last
+                if merge == MergeBehavior::Module
                     && use_trees.len() > 0
                     && rhs_t.use_tree_list().is_some() =>
             {
diff --git a/crates/ide_db/src/search.rs b/crates/ide_db/src/search.rs
index 8f899ea56..67840602b 100644
--- a/crates/ide_db/src/search.rs
+++ b/crates/ide_db/src/search.rs
@@ -233,6 +233,13 @@ impl Definition {
             };
         }
 
+        if let Definition::SelfType(impl_) = self {
+            return match impl_.source(db).map(|src| src.value.syntax().text_range()) {
+                Some(range) => SearchScope::file_range(FileRange { file_id, range }),
+                None => SearchScope::single_file(file_id),
+            };
+        }
+
         if let Definition::GenericParam(hir::GenericParam::LifetimeParam(param)) = self {
             let range = match param.parent(db) {
                 hir::GenericDef::Function(it) => {
@@ -297,7 +304,7 @@ impl Definition {
     }
 
     pub fn usages<'a>(&'a self, sema: &'a Semantics<RootDatabase>) -> FindUsages<'a> {
-        FindUsages { def: self, sema, scope: None, include_self_kw_refs: false }
+        FindUsages { def: self, sema, scope: None, include_self_kw_refs: None }
     }
 }
 
@@ -305,12 +312,13 @@ pub struct FindUsages<'a> {
     def: &'a Definition,
     sema: &'a Semantics<'a, RootDatabase>,
     scope: Option<SearchScope>,
-    include_self_kw_refs: bool,
+    include_self_kw_refs: Option<hir::Type>,
 }
 
 impl<'a> FindUsages<'a> {
-    pub fn include_self_kw_refs(mut self, include: bool) -> FindUsages<'a> {
-        self.include_self_kw_refs = include;
+    /// Enable searching for `Self` when the definition is a type.
+    pub fn include_self_refs(mut self) -> FindUsages<'a> {
+        self.include_self_kw_refs = def_to_ty(self.sema, self.def);
         self
     }
 
@@ -354,13 +362,18 @@ impl<'a> FindUsages<'a> {
             }
         };
 
-        let name = match self.def.name(sema.db) {
-            Some(it) => it.to_string(),
+        let name = self.def.name(sema.db).or_else(|| {
+            self.include_self_kw_refs.as_ref().and_then(|ty| {
+                ty.as_adt()
+                    .map(|adt| adt.name(self.sema.db))
+                    .or_else(|| ty.as_builtin().map(|builtin| builtin.name()))
+            })
+        });
+        let name = match name {
+            Some(name) => name.to_string(),
             None => return,
         };
-
-        let pat = name.as_str();
-        let search_for_self = self.include_self_kw_refs;
+        let name = name.as_str();
 
         for (file_id, search_range) in search_scope {
             let text = sema.db.file_text(file_id);
@@ -369,51 +382,63 @@ impl<'a> FindUsages<'a> {
 
             let tree = Lazy::new(|| sema.parse(file_id).syntax().clone());
 
-            let mut handle_match = |idx: usize| -> bool {
+            for (idx, _) in text.match_indices(name) {
                 let offset: TextSize = idx.try_into().unwrap();
                 if !search_range.contains_inclusive(offset) {
-                    return false;
+                    continue;
                 }
 
                 if let Some(name) = sema.find_node_at_offset_with_descend(&tree, offset) {
-                    match name {
-                        ast::NameLike::NameRef(name_ref) => {
-                            if self.found_name_ref(&name_ref, sink) {
-                                return true;
-                            }
-                        }
-                        ast::NameLike::Name(name) => {
-                            if self.found_name(&name, sink) {
-                                return true;
-                            }
-                        }
-                        ast::NameLike::Lifetime(lifetime) => {
-                            if self.found_lifetime(&lifetime, sink) {
-                                return true;
-                            }
-                        }
+                    if match name {
+                        ast::NameLike::NameRef(name_ref) => self.found_name_ref(&name_ref, sink),
+                        ast::NameLike::Name(name) => self.found_name(&name, sink),
+                        ast::NameLike::Lifetime(lifetime) => self.found_lifetime(&lifetime, sink),
+                    } {
+                        return;
                     }
                 }
-
-                return false;
-            };
-
-            for (idx, _) in text.match_indices(pat) {
-                if handle_match(idx) {
-                    return;
-                }
             }
-
-            if search_for_self {
+            if let Some(self_ty) = &self.include_self_kw_refs {
                 for (idx, _) in text.match_indices("Self") {
-                    if handle_match(idx) {
-                        return;
+                    let offset: TextSize = idx.try_into().unwrap();
+                    if !search_range.contains_inclusive(offset) {
+                        continue;
+                    }
+
+                    if let Some(ast::NameLike::NameRef(name_ref)) =
+                        sema.find_node_at_offset_with_descend(&tree, offset)
+                    {
+                        if self.found_self_ty_name_ref(&self_ty, &name_ref, sink) {
+                            return;
+                        }
                     }
                 }
             }
         }
     }
 
+    fn found_self_ty_name_ref(
+        &self,
+        self_ty: &hir::Type,
+        name_ref: &ast::NameRef,
+        sink: &mut dyn FnMut(FileId, FileReference) -> bool,
+    ) -> bool {
+        match NameRefClass::classify(self.sema, &name_ref) {
+            Some(NameRefClass::Definition(Definition::SelfType(impl_)))
+                if impl_.self_ty(self.sema.db) == *self_ty =>
+            {
+                let FileRange { file_id, range } = self.sema.original_range(name_ref.syntax());
+                let reference = FileReference {
+                    range,
+                    name: ast::NameLike::NameRef(name_ref.clone()),
+                    access: None,
+                };
+                sink(file_id, reference)
+            }
+            _ => false,
+        }
+    }
+
     fn found_lifetime(
         &self,
         lifetime: &ast::Lifetime,
@@ -429,7 +454,7 @@ impl<'a> FindUsages<'a> {
                 };
                 sink(file_id, reference)
             }
-            _ => false, // not a usage
+            _ => false,
         }
     }
 
@@ -448,42 +473,35 @@ impl<'a> FindUsages<'a> {
                 };
                 sink(file_id, reference)
             }
-            Some(NameRefClass::Definition(Definition::SelfType(impl_))) => {
-                let ty = impl_.self_ty(self.sema.db);
-
-                if let Some(adt) = ty.as_adt() {
-                    if &Definition::ModuleDef(ModuleDef::Adt(adt)) == self.def {
-                        let FileRange { file_id, range } =
-                            self.sema.original_range(name_ref.syntax());
-                        let reference = FileReference {
-                            range,
-                            name: ast::NameLike::NameRef(name_ref.clone()),
-                            access: None,
-                        };
-                        return sink(file_id, reference);
-                    }
+            Some(NameRefClass::Definition(def)) if self.include_self_kw_refs.is_some() => {
+                if self.include_self_kw_refs == def_to_ty(self.sema, &def) {
+                    let FileRange { file_id, range } = self.sema.original_range(name_ref.syntax());
+                    let reference = FileReference {
+                        range,
+                        name: ast::NameLike::NameRef(name_ref.clone()),
+                        access: reference_access(&def, &name_ref),
+                    };
+                    sink(file_id, reference)
+                } else {
+                    false
                 }
-
-                false
             }
             Some(NameRefClass::FieldShorthand { local_ref: local, field_ref: field }) => {
                 let FileRange { file_id, range } = self.sema.original_range(name_ref.syntax());
-                let reference = match self.def {
-                    Definition::Field(_) if &field == self.def => FileReference {
-                        range,
-                        name: ast::NameLike::NameRef(name_ref.clone()),
-                        access: reference_access(&field, &name_ref),
-                    },
-                    Definition::Local(l) if &local == l => FileReference {
-                        range,
-                        name: ast::NameLike::NameRef(name_ref.clone()),
-                        access: reference_access(&Definition::Local(local), &name_ref),
-                    },
-                    _ => return false, // not a usage
+                let access = match self.def {
+                    Definition::Field(_) if &field == self.def => {
+                        reference_access(&field, &name_ref)
+                    }
+                    Definition::Local(l) if &local == l => {
+                        reference_access(&Definition::Local(local), &name_ref)
+                    }
+                    _ => return false,
                 };
+                let reference =
+                    FileReference { range, name: ast::NameLike::NameRef(name_ref.clone()), access };
                 sink(file_id, reference)
             }
-            _ => false, // not a usage
+            _ => false,
         }
     }
 
@@ -513,11 +531,30 @@ impl<'a> FindUsages<'a> {
                     FileReference { range, name: ast::NameLike::Name(name.clone()), access: None };
                 sink(file_id, reference)
             }
-            _ => false, // not a usage
+            _ => false,
         }
     }
 }
 
+fn def_to_ty(sema: &Semantics<RootDatabase>, def: &Definition) -> Option<hir::Type> {
+    match def {
+        Definition::ModuleDef(def) => match def {
+            ModuleDef::Adt(adt) => Some(adt.ty(sema.db)),
+            ModuleDef::TypeAlias(it) => Some(it.ty(sema.db)),
+            ModuleDef::BuiltinType(it) => {
+                let graph = sema.db.crate_graph();
+                let krate = graph.iter().next()?;
+                let root_file = graph[krate].root_file_id;
+                let module = sema.to_module_def(root_file)?;
+                Some(it.ty(sema.db, module))
+            }
+            _ => None,
+        },
+        Definition::SelfType(it) => Some(it.self_ty(sema.db)),
+        _ => None,
+    }
+}
+
 fn reference_access(def: &Definition, name_ref: &ast::NameRef) -> Option<ReferenceAccess> {
     // Only Locals and Fields have accesses for now.
     if !matches!(def, Definition::Local(_) | Definition::Field(_)) {
diff --git a/crates/ide_db/src/ty_filter.rs b/crates/ide_db/src/ty_filter.rs
index 988ecd060..00678bf3e 100644
--- a/crates/ide_db/src/ty_filter.rs
+++ b/crates/ide_db/src/ty_filter.rs
@@ -43,7 +43,7 @@ impl TryEnum {
     pub fn sad_pattern(self) -> ast::Pat {
         match self {
             TryEnum::Result => make::tuple_struct_pat(
-                make::path_unqualified(make::path_segment(make::name_ref("Err"))),
+                make::ext::ident_path("Err"),
                 iter::once(make::wildcard_pat().into()),
             )
             .into(),
@@ -54,12 +54,12 @@ impl TryEnum {
     pub fn happy_pattern(self) -> ast::Pat {
         match self {
             TryEnum::Result => make::tuple_struct_pat(
-                make::path_unqualified(make::path_segment(make::name_ref("Ok"))),
+                make::ext::ident_path("Ok"),
                 iter::once(make::wildcard_pat().into()),
             )
             .into(),
             TryEnum::Option => make::tuple_struct_pat(
-                make::path_unqualified(make::path_segment(make::name_ref("Some"))),
+                make::ext::ident_path("Some"),
                 iter::once(make::wildcard_pat().into()),
             )
             .into(),