[danieljbruce]

Description

Replaces global proxyquire shim with local test helper in logging and pubsub.

Impact

Removes --proxyquire-shim from logging, logging-bunyan, logging-winston, and pubsub test scripts.

Changes

• Part 3 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 common, bigquery, datastore, and dns #9639.
• handwritten/logging, handwritten/logging-bunyan, handwritten/logging-winston, handwritten/pubsub: Add local test/proxyquire.ts helper built on Module.prototype.require and require.cache.
• Update unit test imports in those four packages to use ./proxyquire and remove --proxyquire-shim from their package.json test scripts.

Testing

• Executed pnpm test under both Node.js and Bun (JS_RUNTIME=bun) in handwritten/logging, handwritten/logging-bunyan, handwritten/logging-winston, and handwritten/pubsub.
• Verified strict lint and type checks pass via bin/linter.mjs --strict.

Alternatives

• Not merging this pull request was considered, which would keep the Logging and Pub/Sub packages dependent on 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 and replaces the global proxyquire dependency with either a custom local implementation or direct sinon stubbing. In packages/google-cloud-translate/test/index.ts, proxyquire is replaced with a manual Module.prototype.require override. A critical feedback item points out that if the required module was not previously cached, the stubbed version remains in require.cache after the hook finishes, potentially polluting subsequent tests. It is recommended to explicitly delete the module from the cache in this scenario.

[gemini-code-assist]

If cached is undefined (meaning the module was not previously loaded), the stubbed version of ../src/v2 remains in require.cache after the before hook finishes. This will pollute subsequent tests that require ../src/v2 by serving them the stubbed version instead of the real one. To prevent test pollution, explicitly delete the module from require.cache if it was not previously cached.

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