Remove const

- Add test for @ matching
- Address comments

crates/ra_ide/src/completion/complete_pattern.rs

@@ -97,6 +97,13 @@ mod tests {
                 insert: "Z",
                 kind: Const,
             },
+            CompletionItem {
+                label: "Z",
+                source_range: [246; 246),
+                delete: [246; 246),
+                insert: "Z",
+                kind: Const,
+            },
             CompletionItem {
                 label: "m",
                 source_range: [246; 246),
@@ -138,6 +145,21 @@ mod tests {
                 insert: "E",
                 kind: Enum,
             },
+            CompletionItem {
+                label: "E",
+                source_range: [151; 151),
+                delete: [151; 151),
+                insert: "E",
+                kind: Enum,
+            },
+            CompletionItem {
+                label: "m!",
+                source_range: [151; 151),
+                delete: [151; 151),
+                insert: "m!($0)",
+                kind: Macro,
+                detail: "macro_rules! m",
+            },
         ]
         "###);
     }

crates/ra_ide/src/completion/complete_scope.rs

@@ -11,7 +11,6 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) {
     ctx.scope().process_all_names(&mut |name, res| match (ctx.is_pat_binding_and_path, &res) {
         (true, ScopeDef::ModuleDef(ModuleDef::Function(..))) => (),
         (true, ScopeDef::ModuleDef(ModuleDef::Static(..))) => (),
-        (true, ScopeDef::ModuleDef(ModuleDef::Const(..))) => (),
         (true, ScopeDef::Local(..)) => (),
         _ => acc.add_resolution(ctx, name.to_string(), &res),
     });
@@ -27,6 +26,27 @@ mod tests {
         do_completion(ra_fixture, CompletionKind::Reference)
     }
 
+    #[test]
+    fn bind_pat_and_path_ignore_at() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                r"
+                enum Enum {
+                    A,
+                    B,
+                }
+                fn quux(x: Option<Enum>) {
+                    match x {
+                        None => (),
+                        Some(en<|> @ Enum::A) => (),
+                    }
+                }
+                "
+            ),
+            @r###"[]"###
+        );
+    }
+
     #[test]
     fn bind_pat_and_path_ignore_ref() {
         assert_debug_snapshot!(

crates/ra_ide/src/completion/completion_context.rs

@@ -197,11 +197,11 @@ impl<'a> CompletionContext<'a> {
                     self.is_pat_binding = true;
                 }
 
-                if parent.and_then(ast::RecordFieldPatList::cast).is_none() {
-                    let bind_pat_string = bind_pat.syntax().to_string();
-                    if !bind_pat_string.contains("ref ") && !bind_pat_string.contains(" @ ") {
-                        self.is_pat_binding_and_path = true;
-                    }
+                if parent.and_then(ast::RecordFieldPatList::cast).is_none()
+                    && bind_pat.pat().is_none()
+                    && !bind_pat.is_ref()
+                {
+                    self.is_pat_binding_and_path = true;
                 }
             }
             if is_node::<ast::Param>(name.syntax()) {