How to use the power-assert.fail function in power-assert

form.submit(`http://localhost:${port}${apiPath}`, (err, res) => {
      if (err) {
        assert.fail(err);
      }

      assertStream.expect({
        path: /public/
      });
      res.pipe(assertStream);
      assertStream.on("finish", () => {
        server.close();
      });
    });
  });

it("can handle rep", () => {
        const rep = new Rep(AnyAnnotation);
        const src = `@ChangeControlled @Donkey("24", name = "Eeyore") public void magic() {}`;
        const match = rep.matchPrefix(inputStateFromString(src), {}, {});
        if (isSuccessfulMatch(match)) {
            const mmmm = match.match as any;
            assert(mmmm.$matched.trim() === `@ChangeControlled @Donkey("24", name = "Eeyore")`);

        } else {
            assert.fail("Didn't match");
        }
    });

.then(res => {
          assert.fail(res, '', 'unexpected result')
        }, err => {
          assert(err instanceof Error)

fetch: function () {
        assert.fail('should not have called fetch');
      },
      resourceLocation: 'http://example.com/'

.use('/linked/:to', ({ params, resolve }) => {
        ++called
        assert.fail('should not route due to default prevented')
        resolve()
      })

}, error => {
          assert.fail(error);
        }, () => {
          assert(actual.length == expected.length);

.use('/hash', () => {
        assert.fail('must not match from hash when pathname routing')
      })
      .use(({ path }) => {

.use('/linked/:to', ({ params, resolve }) => {
        ++called
        assert.fail('should not route due to target attribute')
      })

.then(function () {
        assert.fail('expected rejected promise');
      }, function (err) {
        assert(err);

beginTransaction: () => {
        assert.fail();
      }
    };