fix: Make mocks pretty-format-able

This covers the case of mocks returning other mocks where, if there is
an error message to be printed, the returned mock will go through
pretty-format.

Author: NiGhTTraX

src/base-repository.ts

@@ -76,7 +76,16 @@ export abstract class BaseRepository implements ExpectationRepository {
         return () => 'mock';
       case '@@toStringTag':
       case Symbol.toStringTag:
+      case 'name':
         return 'mock';
+
+      // pretty-format
+      case '$$typeof':
+      case 'constructor':
+      case '@@__IMMUTABLE_ITERABLE__@@':
+      case '@@__IMMUTABLE_RECORD__@@':
+        return null;
+
       case ApplyProp:
         return (...args: any[]) => {
           this.recordUnexpected(property, args);

tests/instance.spec.ts

@@ -1,8 +1,10 @@
+import { printExpected } from 'jest-matcher-utils';
 import { expect } from 'tdd-buffet/expect/jest';
 import { describe, it } from 'tdd-buffet/suite/node';
 import { instance } from '../src';
 import { ApplyProp } from '../src/expectation';
 import { mock } from '../src/mock';
+import { expectAnsilessEqual } from './ansiless';
 import { SpyRepository } from './expectation-repository';
 
 describe('instance', () => {
@@ -29,4 +31,11 @@ describe('instance', () => {
     expect(instance(foo).bar).toEqual(42);
     expect(repo.getCalledWith).toEqual(['bar']);
   });
+
+  it('should pretty print', () => {
+    expectAnsilessEqual(
+      printExpected(instance(mock<any>())),
+      '[Function mock]'
+    );
+  });
 });

tests/repo-contract.ts

@@ -265,9 +265,9 @@ export const repoContractTests: ExpectationRepositoryContract = {
     {
       name: 'should return values for toString and friends',
       test: (repo) => () => {
-        expect(repo.get('toString')()).not.toHaveLength(0);
-        expect(repo.get('@@toStringTag')).not.toHaveLength(0);
-        expect(repo.get(Symbol.toStringTag)).not.toHaveLength(0);
+        expect(repo.get('toString')()).toBeTruthy();
+        expect(repo.get('@@toStringTag')).toBeTruthy();
+        expect(repo.get(Symbol.toStringTag)).toBeTruthy();
       },
     },
     {