Protected constructors accessible in subclass static methods

src/compiler/checker.ts

@@ -11544,8 +11544,20 @@ namespace ts {
             const declaringClassDeclaration = <ClassLikeDeclaration>getClassLikeDeclarationOfSymbol(declaration.parent.symbol);
             const declaringClass = <InterfaceType>getDeclaredTypeOfSymbol(declaration.parent.symbol);
 
-            // A private or protected constructor can only be instantiated within it's own class
+            // A private or protected constructor can only be instantiated within its own class (or a subclass, for protected)
             if (!isNodeWithinClass(node, declaringClassDeclaration)) {
+                const containingClass = getContainingClass(node);
+                if (containingClass) {
+                    const containingType = getTypeOfNode(containingClass);
+                    const baseTypes = getBaseTypes(<InterfaceType>containingType);
+                    if (baseTypes.length) {
+                        const baseType = baseTypes[0];
+                        if (flags & NodeFlags.Protected &&
+                            baseType.symbol === declaration.parent.symbol) {
+                            return true;
+                        }
+                    }
+                }
                 if (flags & NodeFlags.Private) {
                     error(node, Diagnostics.Constructor_of_class_0_is_private_and_only_accessible_within_the_class_declaration, typeToString(declaringClass));
                 }

tests/baselines/reference/classConstructorAccessibility2.errors.txt

@@ -1,8 +1,8 @@
-tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(26,28): error TS2674: Constructor of class 'BaseB' is protected and only accessible within the class declaration.
-tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(29,24): error TS2675: Cannot extend a class 'BaseC'. Class constructor is marked as private.
-tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(32,28): error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
-tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(36,10): error TS2674: Constructor of class 'BaseB' is protected and only accessible within the class declaration.
-tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(37,10): error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(32,24): error TS2675: Cannot extend a class 'BaseC'. Class constructor is marked as private.
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(35,28): error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(36,35): error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(40,10): error TS2674: Constructor of class 'BaseB' is protected and only accessible within the class declaration.
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts(41,10): error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
 
 
 ==== tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts (5 errors) ====
@@ -14,35 +14,39 @@ tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessib
 
     class BaseB {
         protected constructor(public x: number) { }
-        createInstance() { new BaseB(1); }
+        createInstance() { new BaseB(2); }
     }
 
     class BaseC {
-         private constructor(public x: number) { }
-         createInstance() { new BaseC(1); }
+        private constructor(public x: number) { }
+        createInstance() { new BaseC(3); }
+        static staticInstance() { new BaseC(4); }
     }
 
     class DerivedA extends BaseA {
         constructor(public x: number) { super(x); }
-        createInstance() { new DerivedA(1); }
-        createBaseInstance() { new BaseA(1); }
+        createInstance() { new DerivedA(5); }
+        createBaseInstance() { new BaseA(6); }
+        static staticBaseInstance() { new BaseA(7); }
     }
 
     class DerivedB extends BaseB {
         constructor(public x: number) { super(x); }
-        createInstance() { new DerivedB(1); }
-        createBaseInstance() { new BaseB(1); } // error
-                               ~~~~~~~~~~~~
-!!! error TS2674: Constructor of class 'BaseB' is protected and only accessible within the class declaration.
+        createInstance() { new DerivedB(7); }
+        createBaseInstance() { new BaseB(8); } // ok
+        static staticBaseInstance() { new BaseB(9); } // ok
     }
 
     class DerivedC extends BaseC { // error
                            ~~~~~
 !!! error TS2675: Cannot extend a class 'BaseC'. Class constructor is marked as private.
         constructor(public x: number) { super(x); }
-        createInstance() { new DerivedC(1); }
-        createBaseInstance() { new BaseC(1); } // error
-                               ~~~~~~~~~~~~
+        createInstance() { new DerivedC(9); }
+        createBaseInstance() { new BaseC(10); } // error
+                               ~~~~~~~~~~~~~
+!!! error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
+        static staticBaseInstance() { new BaseC(11); } // error
+                                      ~~~~~~~~~~~~~
 !!! error TS2673: Constructor of class 'BaseC' is private and only accessible within the class declaration.
     }
 
@@ -56,4 +60,5 @@ tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessib
 
     var da = new DerivedA(1);
     var db = new DerivedB(1);
-    var dc = new DerivedC(1);
+    var dc = new DerivedC(1);
+

tests/baselines/reference/classConstructorAccessibility2.js

@@ -7,30 +7,34 @@ class BaseA {
 
 class BaseB {
     protected constructor(public x: number) { }
-    createInstance() { new BaseB(1); }
+    createInstance() { new BaseB(2); }
 }
 
 class BaseC {
-     private constructor(public x: number) { }
-     createInstance() { new BaseC(1); }
+    private constructor(public x: number) { }
+    createInstance() { new BaseC(3); }
+    static staticInstance() { new BaseC(4); }
 }
 
 class DerivedA extends BaseA {
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedA(1); }
-    createBaseInstance() { new BaseA(1); }
+    createInstance() { new DerivedA(5); }
+    createBaseInstance() { new BaseA(6); }
+    static staticBaseInstance() { new BaseA(7); }
 }
 
 class DerivedB extends BaseB {
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedB(1); }
-    createBaseInstance() { new BaseB(1); } // error
+    createInstance() { new DerivedB(7); }
+    createBaseInstance() { new BaseB(8); } // ok
+    static staticBaseInstance() { new BaseB(9); } // ok
 }
 
 class DerivedC extends BaseC { // error
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedC(1); }
-    createBaseInstance() { new BaseC(1); } // error
+    createInstance() { new DerivedC(9); }
+    createBaseInstance() { new BaseC(10); } // error
+    static staticBaseInstance() { new BaseC(11); } // error
 }
 
 var ba = new BaseA(1);
@@ -39,7 +43,8 @@ var bc = new BaseC(1); // error
 
 var da = new DerivedA(1);
 var db = new DerivedB(1);
-var dc = new DerivedC(1);
+var dc = new DerivedC(1);
+
 
 //// [classConstructorAccessibility2.js]
 var __extends = (this && this.__extends) || function (d, b) {
@@ -58,14 +63,15 @@ var BaseB = (function () {
     function BaseB(x) {
         this.x = x;
     }
-    BaseB.prototype.createInstance = function () { new BaseB(1); };
+    BaseB.prototype.createInstance = function () { new BaseB(2); };
     return BaseB;
 }());
 var BaseC = (function () {
     function BaseC(x) {
         this.x = x;
     }
-    BaseC.prototype.createInstance = function () { new BaseC(1); };
+    BaseC.prototype.createInstance = function () { new BaseC(3); };
+    BaseC.staticInstance = function () { new BaseC(4); };
     return BaseC;
 }());
 var DerivedA = (function (_super) {
@@ -74,8 +80,9 @@ var DerivedA = (function (_super) {
         _super.call(this, x);
         this.x = x;
     }
-    DerivedA.prototype.createInstance = function () { new DerivedA(1); };
-    DerivedA.prototype.createBaseInstance = function () { new BaseA(1); };
+    DerivedA.prototype.createInstance = function () { new DerivedA(5); };
+    DerivedA.prototype.createBaseInstance = function () { new BaseA(6); };
+    DerivedA.staticBaseInstance = function () { new BaseA(7); };
     return DerivedA;
 }(BaseA));
 var DerivedB = (function (_super) {
@@ -84,8 +91,9 @@ var DerivedB = (function (_super) {
         _super.call(this, x);
         this.x = x;
     }
-    DerivedB.prototype.createInstance = function () { new DerivedB(1); };
-    DerivedB.prototype.createBaseInstance = function () { new BaseB(1); }; // error
+    DerivedB.prototype.createInstance = function () { new DerivedB(7); };
+    DerivedB.prototype.createBaseInstance = function () { new BaseB(8); }; // ok
+    DerivedB.staticBaseInstance = function () { new BaseB(9); }; // ok
     return DerivedB;
 }(BaseB));
 var DerivedC = (function (_super) {
@@ -94,8 +102,9 @@ var DerivedC = (function (_super) {
         _super.call(this, x);
         this.x = x;
     }
-    DerivedC.prototype.createInstance = function () { new DerivedC(1); };
-    DerivedC.prototype.createBaseInstance = function () { new BaseC(1); }; // error
+    DerivedC.prototype.createInstance = function () { new DerivedC(9); };
+    DerivedC.prototype.createBaseInstance = function () { new BaseC(10); }; // error
+    DerivedC.staticBaseInstance = function () { new BaseC(11); }; // error
     return DerivedC;
 }(BaseC));
 var ba = new BaseA(1);
@@ -121,24 +130,28 @@ declare class BaseC {
     x: number;
     private constructor(x);
     createInstance(): void;
+    static staticInstance(): void;
 }
 declare class DerivedA extends BaseA {
     x: number;
     constructor(x: number);
     createInstance(): void;
     createBaseInstance(): void;
+    static staticBaseInstance(): void;
 }
 declare class DerivedB extends BaseB {
     x: number;
     constructor(x: number);
     createInstance(): void;
     createBaseInstance(): void;
+    static staticBaseInstance(): void;
 }
 declare class DerivedC extends BaseC {
     x: number;
     constructor(x: number);
     createInstance(): void;
     createBaseInstance(): void;
+    static staticBaseInstance(): void;
 }
 declare var ba: BaseA;
 declare var bb: any;

tests/baselines/reference/classConstructorAccessibility5.errors.txt

@@ -0,0 +1,17 @@
+tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility5.ts(9,21): error TS2674: Constructor of class 'Base' is protected and only accessible within the class declaration.
+
+
+==== tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility5.ts (1 errors) ====
+    class Base {
+        protected constructor() { }
+    }
+    class Derived extends Base {
+        static make() { new Base() } // ok
+    }
+
+    class Unrelated {
+        static fake() { new Base() } // error
+                        ~~~~~~~~~~
+!!! error TS2674: Constructor of class 'Base' is protected and only accessible within the class declaration.
+    }
+

tests/baselines/reference/classConstructorAccessibility5.js

@@ -0,0 +1,38 @@
+//// [classConstructorAccessibility5.ts]
+class Base {
+    protected constructor() { }
+}
+class Derived extends Base {
+    static make() { new Base() } // ok
+}
+
+class Unrelated {
+    static fake() { new Base() } // error
+}
+
+
+//// [classConstructorAccessibility5.js]
+var __extends = (this && this.__extends) || function (d, b) {
+    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+    function __() { this.constructor = d; }
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+};
+var Base = (function () {
+    function Base() {
+    }
+    return Base;
+}());
+var Derived = (function (_super) {
+    __extends(Derived, _super);
+    function Derived() {
+        _super.apply(this, arguments);
+    }
+    Derived.make = function () { new Base(); }; // ok
+    return Derived;
+}(Base));
+var Unrelated = (function () {
+    function Unrelated() {
+    }
+    Unrelated.fake = function () { new Base(); }; // error
+    return Unrelated;
+}());

tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility2.ts

@@ -7,30 +7,34 @@ class BaseA {
 
 class BaseB {
     protected constructor(public x: number) { }
-    createInstance() { new BaseB(1); }
+    createInstance() { new BaseB(2); }
 }
 
 class BaseC {
-     private constructor(public x: number) { }
-     createInstance() { new BaseC(1); }
+    private constructor(public x: number) { }
+    createInstance() { new BaseC(3); }
+    static staticInstance() { new BaseC(4); }
 }
 
 class DerivedA extends BaseA {
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedA(1); }
-    createBaseInstance() { new BaseA(1); }
+    createInstance() { new DerivedA(5); }
+    createBaseInstance() { new BaseA(6); }
+    static staticBaseInstance() { new BaseA(7); }
 }
 
 class DerivedB extends BaseB {
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedB(1); }
-    createBaseInstance() { new BaseB(1); } // error
+    createInstance() { new DerivedB(7); }
+    createBaseInstance() { new BaseB(8); } // ok
+    static staticBaseInstance() { new BaseB(9); } // ok
 }
 
 class DerivedC extends BaseC { // error
     constructor(public x: number) { super(x); }
-    createInstance() { new DerivedC(1); }
-    createBaseInstance() { new BaseC(1); } // error
+    createInstance() { new DerivedC(9); }
+    createBaseInstance() { new BaseC(10); } // error
+    static staticBaseInstance() { new BaseC(11); } // error
 }
 
 var ba = new BaseA(1);
@@ -39,4 +43,4 @@ var bc = new BaseC(1); // error
 
 var da = new DerivedA(1);
 var db = new DerivedB(1);
-var dc = new DerivedC(1);
+var dc = new DerivedC(1);

tests/cases/conformance/classes/constructorDeclarations/classConstructorAccessibility5.ts

@@ -0,0 +1,10 @@
+class Base {
+    protected constructor() { }
+}
+class Derived extends Base {
+    static make() { new Base() } // ok
+}
+
+class Unrelated {
+    static fake() { new Base() } // error
+}