Jasmine - Test suites

Suites: describe Your Tests

A test suite begins with a call to the global Jasmine function describe with two parameters: a string and a function. The string is a name or title for a spec suite - usually what is being tested. The function is a block of code that implements the suite.

Specs

Specs are defined by calling the global Jasmine function it, which, like describe takes a string and a function. The string is the title of the spec and the function is the spec, or test. A spec contains one or more expectations that test the state of the code. An expectation in Jasmine is an assertion that is either true or false. A spec with all true expectations is a passing spec. A spec with one or more false expectations is a failing spec.

Example:

// Angular code
@Injectable({
  providedIn: 'root'
})
export class CalculatorService {
  constructor(private logger: LoggerService) {

  }

  add(n1: number, n2: number) {
    this.logger.log("Addition operation called");
    return n1 + n2;
  }

  subtract(n1: number, n2: number) {
    this.logger.log("Subtraction operation called");
    return n1 - n2;
  }
}

// Spec code
describe('CalculatorService', () => {
    it('should add two numbers', () => {
        pending();
    });

    it('should substract two numbers', () => {
        pending();
    });
});