2 files changed, 190 insertions, 7 deletions

diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index a58fdc036..9ac9768af 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -50,23 +50,46 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
                 hir::ModuleDef::TypeAlias(a) => a.ty(ctx.db),
                 _ => unreachable!(),
             };
+            ctx.analyzer.iterate_path_candidates(ctx.db, ty.clone(), None, |_ty, item| {
+                match item {
+                    hir::AssocItem::Function(func) => {
+                        let data = func.data(ctx.db);
+                        if !data.has_self_param() {
+                            acc.add_function(ctx, func);
+                        }
+                    }
+                    hir::AssocItem::Const(ct) => acc.add_const(ctx, ct),
+                    hir::AssocItem::TypeAlias(ty) => acc.add_type_alias(ctx, ty),
+                }
+                None::<()>
+            });
+            // Iterate assoc types separately
+            // FIXME: complete T::AssocType
             let krate = ctx.module.map(|m| m.krate());
             if let Some(krate) = krate {
                 ty.iterate_impl_items(ctx.db, krate, |item| {
                     match item {
-                        hir::AssocItem::Function(func) => {
-                            let data = func.data(ctx.db);
-                            if !data.has_self_param() {
-                                acc.add_function(ctx, func);
-                            }
-                        }
-                        hir::AssocItem::Const(ct) => acc.add_const(ctx, ct),
+                        hir::AssocItem::Function(_) | hir::AssocItem::Const(_) => {}
                         hir::AssocItem::TypeAlias(ty) => acc.add_type_alias(ctx, ty),
                     }
                     None::<()>
                 });
             }
         }
+        hir::ModuleDef::Trait(t) => {
+            for item in t.items(ctx.db) {
+                match item {
+                    hir::AssocItem::Function(func) => {
+                        let data = func.data(ctx.db);
+                        if !data.has_self_param() {
+                            acc.add_function(ctx, func);
+                        }
+                    }
+                    hir::AssocItem::Const(ct) => acc.add_const(ctx, ct),
+                    hir::AssocItem::TypeAlias(ty) => acc.add_type_alias(ctx, ty),
+                }
+            }
+        }
         _ => {}
     };
 }
@@ -559,6 +582,111 @@ mod tests {
     }
 
     #[test]
+    fn completes_trait_associated_method_1() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                "
+                //- /lib.rs
+                trait Trait {
+                  /// A trait method
+                  fn m();
+                }
+
+                fn foo() { let _ = Trait::<|> }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "m()",
+                source_range: [73; 73),
+                delete: [73; 73),
+                insert: "m()$0",
+                kind: Function,
+                lookup: "m",
+                detail: "fn m()",
+                documentation: Documentation(
+                    "A trait method",
+                ),
+            },
+        ]
+        "###
+        );
+    }
+
+    #[test]
+    fn completes_trait_associated_method_2() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                "
+                //- /lib.rs
+                trait Trait {
+                  /// A trait method
+                  fn m();
+                }
+
+                struct S;
+                impl Trait for S {}
+
+                fn foo() { let _ = S::<|> }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "m()",
+                source_range: [99; 99),
+                delete: [99; 99),
+                insert: "m()$0",
+                kind: Function,
+                lookup: "m",
+                detail: "fn m()",
+                documentation: Documentation(
+                    "A trait method",
+                ),
+            },
+        ]
+        "###
+        );
+    }
+
+    #[test]
+    fn completes_trait_associated_method_3() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                "
+                //- /lib.rs
+                trait Trait {
+                  /// A trait method
+                  fn m();
+                }
+
+                struct S;
+                impl Trait for S {}
+
+                fn foo() { let _ = <S as Trait>::<|> }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "m()",
+                source_range: [110; 110),
+                delete: [110; 110),
+                insert: "m()$0",
+                kind: Function,
+                lookup: "m",
+                detail: "fn m()",
+                documentation: Documentation(
+                    "A trait method",
+                ),
+            },
+        ]
+        "###
+        );
+    }
+
+    #[test]
     fn completes_type_alias() {
         assert_debug_snapshot!(
             do_reference_completion(
diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 323faab33..c1ce54bea 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -390,6 +390,61 @@ mod tests {
             "spam RECORD_FIELD_DEF FileId(1) [17; 26) [17; 21)",
         );
     }
+
+    #[test]
+    fn goto_definition_works_for_ufcs_inherent_methods() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo;
+            impl Foo {
+                fn frobnicate() {  }
+            }
+
+            fn bar(foo: &Foo) {
+                Foo::frobnicate<|>();
+            }
+            ",
+            "frobnicate FN_DEF FileId(1) [27; 47) [30; 40)",
+        );
+    }
+
+    #[test]
+    fn goto_definition_works_for_ufcs_trait_methods_through_traits() {
+        check_goto(
+            "
+            //- /lib.rs
+            trait Foo {
+                fn frobnicate();
+            }
+
+            fn bar() {
+                Foo::frobnicate<|>();
+            }
+            ",
+            "frobnicate FN_DEF FileId(1) [16; 32) [19; 29)",
+        );
+    }
+
+    #[test]
+    fn goto_definition_works_for_ufcs_trait_methods_through_self() {
+        check_goto(
+            "
+            //- /lib.rs
+            struct Foo;
+            trait Trait {
+                fn frobnicate();
+            }
+            impl Trait for Foo {}
+
+            fn bar() {
+                Foo::frobnicate<|>();
+            }
+            ",
+            "frobnicate FN_DEF FileId(1) [30; 46) [33; 43)",
+        );
+    }
+
     #[test]
     fn goto_definition_on_self() {
         check_goto(