fix typeof completions broken

Author: Kingwl

src/compiler/checker.ts

@@ -19263,8 +19263,8 @@ namespace ts {
             }
         }
 
-        function isValidPropertyAccessForCompletions(node: PropertyAccessExpression | ImportTypeNode, type: Type, property: Symbol): boolean {
-            return isValidPropertyAccessWithType(node, node.kind !== SyntaxKind.ImportType && node.expression.kind === SyntaxKind.SuperKeyword, property.escapedName, type)
+        function isValidPropertyAccessForCompletions(node: PropertyAccessExpression | ImportTypeNode | QualifiedName, type: Type, property: Symbol): boolean {
+            return isValidPropertyAccessWithType(node, node.kind === SyntaxKind.PropertyAccessExpression && node.expression.kind === SyntaxKind.SuperKeyword, property.escapedName, type)
                 && (!(property.flags & SymbolFlags.Method) || isValidMethodAccess(property, type));
         }
         function isValidMethodAccess(method: Symbol, actualThisType: Type): boolean {

src/compiler/types.ts

@@ -3108,7 +3108,7 @@ namespace ts {
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): string | number | undefined;
         isValidPropertyAccess(node: PropertyAccessExpression | QualifiedName | ImportTypeNode, propertyName: string): boolean;
         /** Exclude accesses to private properties or methods with a `this` parameter that `type` doesn't satisfy. */
-        /* @internal */ isValidPropertyAccessForCompletions(node: PropertyAccessExpression | ImportTypeNode, type: Type, property: Symbol): boolean;
+        /* @internal */ isValidPropertyAccessForCompletions(node: PropertyAccessExpression | ImportTypeNode | QualifiedName, type: Type, property: Symbol): boolean;
         /** Follow all aliases to get the original symbol. */
         getAliasedSymbol(symbol: Symbol): Symbol;
         /** Follow a *single* alias to get the immediately aliased symbol. */

src/services/completions.ts

@@ -913,7 +913,7 @@ namespace ts.Completions {
             }
             else {
                 for (const symbol of type.getApparentProperties()) {
-                    if (typeChecker.isValidPropertyAccessForCompletions(node.kind === SyntaxKind.ImportType ? <ImportTypeNode>node : <PropertyAccessExpression>node.parent, type, symbol)) {
+                    if (typeChecker.isValidPropertyAccessForCompletions(node.kind === SyntaxKind.ImportType ? <ImportTypeNode>node : <PropertyAccessExpression | QualifiedName>node.parent, type, symbol)) {
                         addPropertySymbol(symbol);
                     }
                 }

tests/cases/fourslash/completionTypeofExpressions.ts

@@ -0,0 +1,15 @@
+/// <reference path="fourslash.ts" />
+
+//// const x = "str";
+//// function test(arg: typeof x./*1*/) {}
+//// function test1(arg: typeof (x./*2*/)) {}
+
+verify.completions({
+    marker: "1",
+    includes: ['length']
+});
+
+verify.completions({
+    marker: "2",
+    includes: ['length']
+});