expect extension to use Jest's toMatchSnapshot in Mocha

The module uses jest-snapshot under the hood and works as an extension to [email protected] to enable snapshot-testing in mocha.

All credit goes to Alexander Beletsky. See his blog post about snapshot-testing in Mocha here.

const expect = require("expect");
const toMatchSnapshot = require("expect-mocha-snapshot");

expect.extend({ toMatchSnapshot });

describe("foo", function() {
  it("matches the snapshot", function() {
    expect({ foo: "bar" }).toMatchSnapshot(this);
  });
});

To create the snapshot or test the code against the created snapshots, just run mocha like you normally would.

mocha

If your tests are failing and you want to update the snapshot, use the environment variable SNAPSHOT_UPDATE.

SNAPSHOT_UPDATE=true mocha

MIT