[danieljbruce]

Description

Removes bin/proxyquire-bun-shim.cjs and all remaining Mocha and runner shim configuration.

Impact

Eliminates the global Bun proxyquire preload shim from the test runner.

Changes

• Part 5 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: remove --proxyquire-shim from bigtable, spanner, and storage #9641.
• Delete bin/proxyquire-bun-shim.cjs.
• Remove --proxyquire-shim, BUN_ENABLE_PROXYQUIRE_SHIM, and proxyquire-bun-shim.cjs preloading from bin/run-test.cjs.
• Remove proxyquire-bun-shim.cjs from .mocharc.cjs and all 11 core/packages/*/.mocharc.js configuration files.

Testing

• Verified unit tests across all migrated packages pass under both Node.js and Bun (JS_RUNTIME=bun) without bin/proxyquire-bun-shim.cjs.
• Verified strict lint and type checks pass via bin/linter.mjs --strict.

Alternatives

• Not merging this pull request was considered, which would leave dead shim code and unused --proxyquire-shim runner flags in the repository.

[gemini-code-assist]

Code Review

This pull request removes the global Bun proxyquire shim and replaces it with package-local proxyquire implementations or direct sinon stubbing across multiple packages. However, critical issues were found in the nodejs-googleapis-common package: instantiating this.GoogleAuth instead of GoogleAuth in authplus.ts will cause a runtime TypeError, and the corresponding unit tests attempt to stub an undefined prototype. The reviewer recommends instantiating GoogleAuth directly and stubbing GoogleAuth.prototype by importing it from google-auth-library.

[gemini-code-assist]

Using this.GoogleAuth will result in a runtime TypeError: this.GoogleAuth is not a constructor because GoogleAuth is not defined as a property on the AuthPlus class or its prototype. It should be instantiated directly using the imported GoogleAuth class.

Suggested change

	this._cachedAuth = new this.GoogleAuth(options);
	this._cachedAuth = new GoogleAuth(options);

References

1. When instantiating a specific client class where the class name is a local constant (and not a dynamic parameter), instantiate the class directly (e.g., new v1.InstanceAdminClient(...)) to ensure type safety and avoid unnecessary dynamic lookups or any casts.

[gemini-code-assist]

Import GoogleAuth from google-auth-library so that its prototype can be stubbed directly in the unit tests.

Suggested change

	import * as assert from 'assert';
	import {describe, it} from 'mocha';
	import * as proxyquire from 'proxyquire';
	import * as AuthPlus from '../src/authplus';
	import {afterEach, describe, it} from 'mocha';
	import * as sinon from 'sinon';
	import {AuthPlus} from '../src/authplus';
	import * as assert from 'assert';
	import {afterEach, describe, it} from 'mocha';
	import * as sinon from 'sinon';
	import {GoogleAuth} from 'google-auth-library';
	import {AuthPlus} from '../src/authplus';

[gemini-code-assist]

Stub GoogleAuth.prototype directly instead of trying to access it via auth.GoogleAuth.prototype, which is undefined and will cause a runtime error.

Suggested change

	sinon
	.stub(auth.GoogleAuth.prototype, 'getClient')
	// eslint-disable-next-line @typescript-eslint/no-explicit-any
	.resolves({} as any);
	sinon
	.stub(GoogleAuth.prototype, 'getClient')
	// eslint-disable-next-line @typescript-eslint/no-explicit-any
	.resolves({} as any);

[danieljbruce]

/gemini review

[gemini-code-assist]

Code Review

This pull request removes the global proxyquire-bun-shim.cjs and the --proxyquire-shim flag from the test runner. Instead, it introduces a local, TypeScript-compatible proxyquire implementation across various package test directories and updates the tests to import it relatively. Additionally, several tests are refactored to use sinon stubbing directly instead of proxyquire, and Spanner observability tests are updated with improved lifecycle hooks for context manager cleanup. I have no feedback to provide as there are no review comments.