Better error messages when failing call verification

src/MethodStubVerificator.ts

@@ -7,6 +7,11 @@ const localSetTimeout = setTimeout;
 export class MethodStubVerificator<T> {
  private methodCallToStringConverter: MethodCallToStringConverter = new MethodCallToStringConverter();
 
+ private actualCalls() {
+ const calls = this.methodToVerify.mocker.getActionsByName(this.methodToVerify.methodName);
+ return 'Actual calls:\n ' + this.methodCallToStringConverter.convertActualCalls(calls).join('\n ');
+ }
+
  constructor(private methodToVerify: MethodToStub) {
  methodToVerify.watcher.invoked();
  }
@@ -34,24 +39,27 @@ export class MethodStubVerificator<T> {
  public times(value: number): void {
  const allMatchingActions = this.methodToVerify.mocker.getAllMatchingActions(this.methodToVerify.methodName, this.methodToVerify.matchers);
  if (value !== allMatchingActions.length) {
- const methodToVerifyAsString = this.methodCallToStringConverter.convert(this.methodToVerify);
- throw new Error(`Expected "${methodToVerifyAsString}to be called ${value} time(s). But has been called ${allMatchingActions.length} time(s).`);
+ const methodToVerifyAsString = this.methodCallToStringConverter.convert(this.methodToVerify); 
+ const msg = `Expected "${methodToVerifyAsString}to be called ${value} time(s). But has been called ${allMatchingActions.length} time(s).`;
+ throw new Error(msg + '\n' + this.actualCalls());
  }
  }
 
  public atLeast(value: number): void {
  const allMatchingActions = this.methodToVerify.mocker.getAllMatchingActions(this.methodToVerify.methodName, this.methodToVerify.matchers);
  if (value > allMatchingActions.length) {
  const methodToVerifyAsString = this.methodCallToStringConverter.convert(this.methodToVerify);
- throw new Error(`Expected "${methodToVerifyAsString}to be called at least ${value} time(s). But has been called ${allMatchingActions.length} time(s).`);
+ const msg = `Expected "${methodToVerifyAsString}to be called at least ${value} time(s). But has been called ${allMatchingActions.length} time(s).`;
+ throw new Error(msg + '\n' + this.actualCalls());
  }
  }
 
  public atMost(value: number): void {
  const allMatchingActions = this.methodToVerify.mocker.getAllMatchingActions(this.methodToVerify.methodName, this.methodToVerify.matchers);
  if (value < allMatchingActions.length) {
  const methodToVerifyAsString = this.methodCallToStringConverter.convert(this.methodToVerify);
- throw new Error(`Expected "${methodToVerifyAsString}to be called at least ${value} time(s). But has been called ${allMatchingActions.length} time(s).`);
+ const msg = `Expected "${methodToVerifyAsString}to be called at most ${value} time(s). But has been called ${allMatchingActions.length} time(s).`;
+ throw new Error(msg + '\n' + this.actualCalls());
  }
  }
 

src/utils/MethodCallToStringConverter.ts

@@ -1,5 +1,6 @@
 import {Matcher} from "../matcher/type/Matcher";
 import {MethodToStub} from "../MethodToStub";
+import { MethodAction } from "../MethodAction";
 
 export class MethodCallToStringConverter {
  public convert(method: MethodToStub): string {
@@ -8,4 +9,8 @@ export class MethodCallToStringConverter {
  const stringifiedMatchers = method.matchers.map((matcher: Matcher) => matcher.toString()).join(", ");
  return `${method.methodName}(${stringifiedMatchers})" `;
  }
+
+ public convertActualCalls(calls: MethodAction[]): string[] {
+ return calls.map(call => call.methodName + '(' + call.args.map(arg => arg.toString()).join(', ') + ')');
+ }
 }

test/verification.spec.ts

@@ -827,6 +827,24 @@ describe("verifying mocked object", () => {
  verify(mockedFoo.getBar()).once();
  });
  });
+
+ describe("matcher error messages", () => {
+ it("should describe expected method call", () => {
+ //given
+ instance(mockedFoo).getStringById(2);
+
+ try {
+ // when
+ verify(mockedFoo.getStringById(1)).once();
+
+ expect(true).toBe(false); // Above call should throw an exception
+ } catch (e) {
+ // then
+ expect(e.message).toMatch(/getStringById\(strictEqual\(1\)\)/);
+ expect(e.message).toMatch(/getStringById\(2\)/);
+ }
+ });
+ });
 });
 
 function verifyCallCountErrorMessage(error, expectedCallCount, receivedCallCount): void {