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Getting Started

Mocking library for TypeScript, inspired by Mockito.

Installation​

npm install @typestrong/ts-mockito --save-dev

Basics​

// Creating mock
let mockedFoo: Foo = mock(Foo);

// Getting instance from mock
let foo: Foo = instance(mockedFoo);

// Using instance in source code
foo.getBar(3);
foo.getBar(5);

// Explicit, readable verification
verify(mockedFoo.getBar(3)).called();
verify(mockedFoo.getBar(anything())).called();

Main features​

  • Strongly typed, with IDE autocomplete
  • Mock creation (mock), including abstract classes - see Mocking types
  • Spying on real objects (spy) - see Spying on real objects
  • Changing mock behavior (when) via thenReturn, thenThrow, thenCall, thenResolve and thenReject - see Stubbing method calls
  • Checking if methods were called with given arguments (verify), including call count and call order - see Verification
  • Resetting mocks (reset, resetCalls) and capturing arguments (capture) - see Resetting and capturing
  • Recording multiple behaviors for the same stub - see Recording multiple behaviors
  • Readable error messages, e.g. 'Expected "convertNumberToString(strictEqual(3))" to be called 2 time(s). But has been called 1 time(s).'

See the full API reference for every exported function and its options.