[danieljbruce]

Description

Replaces global proxyquire shim with local test helper in four packages.

Impact

Removes --proxyquire-shim from common, bigquery, datastore, and google-cloud-dns test scripts.

Changes

• Part 2 of 5 in stacked PR series: test: replace proxyquire with sinon in gax, common, error-reporting, translate #9638 -> test: remove --proxyquire-shim from common, bigquery, datastore, and dns #9639 -> test: remove --proxyquire-shim from logging and pubsub packages #9640 -> test: remove --proxyquire-shim from bigtable, spanner, and storage #9641 -> chore: remove proxyquire-bun-shim.cjs and runner flags #9633 (b/570680750).
• Stacked on test: replace proxyquire with sinon in gax, common, error-reporting, translate #9638.
• core/common, handwritten/bigquery, handwritten/datastore, handwritten/google-cloud-dns: Add a runtime-agnostic test/proxyquire.ts helper built on Module.prototype.require and require.cache that works identically in Node.js and Bun.
• Update test imports in those four packages from 'proxyquire' to './proxyquire' (or relative path) and remove --proxyquire-shim from their package.json test scripts.

Testing

• Executed pnpm test under both Node.js and Bun (JS_RUNTIME=bun) in core/common, handwritten/bigquery, handwritten/datastore, and handwritten/google-cloud-dns.
• Verified strict lint and type checks pass via bin/linter.mjs --strict.

Alternatives

• Not merging this pull request was considered, which would keep these four packages coupled to the global bin/proxyquire-bun-shim.cjs preload shim.

[gemini-code-assist]

Code Review

This pull request removes the --proxyquire-shim test flag across multiple packages, replacing the external proxyquire dependency with a custom local implementation or refactoring tests to use sinon stubs and manual module mocking. The review feedback highlights a few key improvements: first, the custom proxyquire helper hasOwn should be updated to support function stubs; second, the manual module mocking in google-cloud-translate should properly clean up require.cache when the module was not previously cached to avoid test pollution; and finally, the stubbed makeAuthenticatedRequestFactory in error-reporting should return a function rather than a plain object to prevent potential runtime errors.

[gemini-code-assist]

The hasOwn helper currently checks typeof o === 'object'. This will return false if the stub is a function (e.g., a constructor or a stubbed class), preventing properties like @global or @noCallThru from being detected on function stubs. Updating the check to include typeof o === 'function' resolves this issue.

Suggested change

	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && typeof o === 'object' && hasOwnProperty.call(o, k));
	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && (typeof o === 'object' || typeof o === 'function') && hasOwnProperty.call(o, k));

[gemini-code-assist]

The hasOwn helper currently checks typeof o === 'object'. This will return false if the stub is a function (e.g., a constructor or a stubbed class), preventing properties like @global or @noCallThru from being detected on function stubs. Updating the check to include typeof o === 'function' resolves this issue.

Suggested change

	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && typeof o === 'object' && hasOwnProperty.call(o, k));
	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && (typeof o === 'object' || typeof o === 'function') && hasOwnProperty.call(o, k));

[gemini-code-assist]

The hasOwn helper currently checks typeof o === 'object'. This will return false if the stub is a function (e.g., a constructor or a stubbed class), preventing properties like @global or @noCallThru from being detected on function stubs. Updating the check to include typeof o === 'function' resolves this issue.

Suggested change

	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && typeof o === 'object' && hasOwnProperty.call(o, k));
	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && (typeof o === 'object' || typeof o === 'function') && hasOwnProperty.call(o, k));

[gemini-code-assist]

The hasOwn helper currently checks typeof o === 'object'. This will return false if the stub is a function (e.g., a constructor or a stubbed class), preventing properties like @global or @noCallThru from being detected on function stubs. Updating the check to include typeof o === 'function' resolves this issue.

Suggested change

	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && typeof o === 'object' && hasOwnProperty.call(o, k));
	const hasOwn = (o: unknown, k: string) =>
	Boolean(o && (typeof o === 'object' || typeof o === 'function') && hasOwnProperty.call(o, k));

[gemini-code-assist]

If cached is undefined (meaning the module was not previously loaded), the stubbed module remains in require.cache after the test setup. This causes test pollution, as subsequent tests requiring ../src/v2 will receive the stubbed version. Deleting the cache entry when cached is undefined prevents this.

Suggested change

	} finally {
	mod.prototype.require = origRequire;
	if (cached) require.cache[v2Path] = cached;
	}
	} finally {
	mod.prototype.require = origRequire;
	if (cached) {
	require.cache[v2Path] = cached;
	} else {
	delete require.cache[v2Path];
	}
	}

[gemini-code-assist]

The stubbed util.makeAuthenticatedRequestFactory returns a plain object instead of a function. If the constructor or any other code attempts to invoke this.request as a function, it will throw a TypeError. Returning a function with the stubbed properties attached is safer and matches the expected signature.

Suggested change

	util.makeAuthenticatedRequestFactory = (() => ({
	authClient: {
	async getAccessToken() {
	if (errToReturn) {
	throw errToReturn;
	}
	return 'some-token';
	},
	},
	getCredentials: {},
	})) as unknown as typeof util.makeAuthenticatedRequestFactory;
	const fakeRequest = (() => {}) as any;
	fakeRequest.authClient = {
	async getAccessToken() {
	if (errToReturn) {
	throw errToReturn;
	}
	return 'some-token';
	},
	};
	fakeRequest.getCredentials = {};
	util.makeAuthenticatedRequestFactory = (() => fakeRequest) as unknown as typeof util.makeAuthenticatedRequestFactory;