fix(transformer): Keep a bound-state regardless of declaration keys, since such keys may be cached and reused in parallel

A bound state is an indicator whether a new function instance is emitted,
binding this in the current scope. The scope's constructor can then be
referenced with `this.constructor` enabling a reference to the parent
constructor.

Author: martinjlowm

src/transformer/genericDeclaration/genericDeclaration.ts

@@ -167,8 +167,8 @@ export function GenericDeclaration(scope: Scope): IGenericDeclaration {
           }
         }
 
-        if (!typeParameterDeclaration || scope.currentMockKey !== declarationKey) {
-          genericValueDescriptor = GetDescriptor(genericNode, new Scope(declarationKey));
+        if (!typeParameterDeclaration || !scope.isBound()) {
+          genericValueDescriptor = GetDescriptor(genericNode, (new Scope(declarationKey)).bind());
         }
 
         const genericParameter: GenericParameter = createGenericParameter(

src/transformer/scope/scope.ts

@@ -3,12 +3,32 @@ import * as ts from 'typescript';
 export type InterfaceOrClassDeclaration = ts.InterfaceDeclaration | ts.ClassDeclaration;
 export class Scope {
   constructor(currentMockKey?: string) {
+    this._bound = false;
     this._currentMockKey = currentMockKey;
   }
 
   private readonly _currentMockKey: string | undefined;
+  private _bound: boolean;
+
+  private _appendConstructorMarker(): string {
+    return this._bound ? '_C' : '';
+  }
+
+  public bind(): this {
+    this._bound = true;
+
+    return this;
+  }
+
+  public isBound(): boolean {
+    return this._bound;
+  }
 
   public get currentMockKey(): string | undefined {
-    return this._currentMockKey;
+    if (this._currentMockKey === undefined) {
+      return;
+    }
+
+    return this._currentMockKey + this._appendConstructorMarker();
   }
 }