metamask-extension/app/scripts/controllers/network/test/fake-block-tracker.ts

import { PollingBlockTracker } from 'eth-block-tracker';

/**
 * Acts like a PollingBlockTracker, but doesn't start the polling loop or
 * make any requests.
 */
export class FakeBlockTracker extends PollingBlockTracker {
  async _start() {
    // do nothing
  }
}
Use fake provider for NetworkController unit tests (#18628) * Use fake provider for NetworkController unit tests In the unit tests for NetworkController, it's important to prevent network requests from occurring. Currently we do that by using Nock. However, the `core` version of NetworkController uses a fake provider object. This is arguably a better approach for unit tests because it prevents us from having to think about the behavior that a specific middleware may have. For instance, the Infura middleware intercepts `eth_chainId` to return a static result, and the block cache middleware replaces the `latest` block tag with the latest block number, making an extra call to `eth_blockNumber` in doing so. We have to account for these kinds of behaviors when using Nock, but we do not need to do this when using a fake provider. This should make it easier to compare the difference between the unit tests in this repo vs. in the `core` repo, which should ultimately help us merge the two controllers together. * Rename fake-provider-engine to fake-provider * Rearrange imports * Move fake-provider and fake-block-tracker into a directory and exclude it from coverage * Make FakeBlockTracker inert, and fix JSDocs * Remove generics from FakeProvider * Call beforeCompleting (and beforeResolving) using async/await * Fix signature of sendAsync; align other signatures within FakeProvider * No need to check whether error is not a string * Don't exclude the provider-api-tests directory from coverage * Make sure to mock both net_version and eth_getBlockByNumber when testing network status * Fix FakeProvider so that none of the methods have optional callbacks 2023-04-20 19:51:41 +02:00			`import { PollingBlockTracker } from 'eth-block-tracker';`

			`/**`
			`* Acts like a PollingBlockTracker, but doesn't start the polling loop or`
			`* make any requests.`
			`*/`
			`export class FakeBlockTracker extends PollingBlockTracker {`
			`async _start() {`
			`// do nothing`
			`}`
			`}`