Add testing support for 2nd gen firestore triggers

[blidd-google]

2nd gen firestore triggers support is coming soon! This PR will add support for mocking 2nd gen firestore triggers.

Example:

// index.ts
import { onDocumentCreated } from "firebase-functions/v2/firestore";

export const fn = onDocumentCreated("foo/{bar}", (event) => {...});

// index.test.ts
import * as test from "firebase-functions-test";
import { fn } from './index';

const {wrap} = test();
const wrappedFn = wrap(fn);
wrappedFn({
  data: {
    a: 'b',
    c: 'd',
  },
  params: {
    bar: 123,
  },
});

[TheIronDev]

Please fix

[blidd-google]

woah that was the fastest PR review of all time!! will do

[colerogers]

you should be good to grab v 4.3.0 now

[TheIronDev]

nit: remove the "should resolve" ("document path")

[TheIronDev]

is this necessary? (if so can you document why we are checking its an object)

[blidd-google]

I reused the logic from getOrCreateDataSnapshotChange, but actually the data instanceof Object conditional is probably not necessary.

[TheIronDev]

is this || suppose to be a && ? Does getOrCreateDocumentSnapship still work?

[blidd-google]

I used || instead of && because I thought it may be surprising for users who specify an object like

const partial = {
  data: {
    before: {
      foo: 'bar',
    },
}

and expect the generated mock event data to include event.data.before, but if we use &&, they will be required to specify both the before and after objects, and if they don't, the data they provide will be overwritten and they will see the example data in the cloud event instead.

[colerogers]

Looks good - just update the package.json & get tyler's signoff

[colerogers]

same here - 4.3.0