[RFC] enhancement(extension,repository): Add hidden __ident property to mocks and functions to differentiate them in conditional branching

src/extension/method/provider/provider.ts

@@ -1,3 +1,4 @@
+import { applyIdentityProperty } from '../../../utils/applyIdentityProperty';
 import { functionMethod } from './functionMethod';
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 type Method = (name: string, value: any) => () => any;
@@ -45,6 +46,10 @@ export class Provider {
       return this._method(name, value());
     }
 
-    return this._method(name, value);
+    // FIXME: Do this smarter, it's a bit counter intuitive to return a new
+    // proxy every single time this function is called. It should probably mock
+    // based on name if that ends up being a string representing the type
+    // signature.
+    return applyIdentityProperty(this._method, name)(name, value);
   }
 }

src/repository/repository.ts

@@ -1,4 +1,7 @@
-type Factory = Function;
+import { applyIdentityProperty } from '../utils/applyIdentityProperty';
+
+// eslint-disable-next-line
+type Factory = (...args: any[]) => any;
 
 export class Repository {
   private readonly _repository: { [key: string]: Factory };
@@ -15,7 +18,7 @@ export class Repository {
   }
 
   public registerFactory(key: string, factory: Factory): void {
-    this._repository[key] = factory;
+    this._repository[key] = applyIdentityProperty(factory, key);
   }
 
   public getFactory(key: string): Factory {

src/utils/applyIdentityProperty.ts

@@ -0,0 +1,34 @@
+// eslint-disable-next-line
+type Function<K> = (...args: any[]) => K;
+type IdentityFlavored<K> = K & { __ident?: string };
+
+export function applyIdentityProperty<K extends object, T extends Function<K>>(target: T, identity: string): T {
+  return new Proxy(
+    target,
+    {
+      apply(func: T, _this: unknown, args: Parameters<T>): IdentityFlavored<K> | undefined {
+        const t: IdentityFlavored<K> = func(...args);
+
+        if (typeof t === 'undefined') {
+          return;
+        }
+
+        if (!(t instanceof Object)) {
+          return t;
+        }
+
+        if (typeof t.__ident !== 'undefined') {
+          return t;
+        }
+
+        Object.defineProperty(t, '__ident', {
+          enumerable: false,
+          writable: false,
+          value: identity,
+        });
+
+        return t;
+      },
+    },
+  );
+}