feat(core): implement generic CacheService and optimize setupUser

[sehoon38]

Summary

Introduces a generic, type-safe CacheService in the core package and refactors setupUser to use it. This provides a consistent way to handle in-memory caching with TTL support and automatic promise cleanup across the project.

Details

• packages/core/src/utils/cache.ts:
  • Implemented CacheService supporting both Map and WeakMap backends.
  • Added TTL (Time To Live) support for automatic entry expiration.
  • Added automatic removal of failed promises from the cache to allow immediate retries.
  • Exported a globalCache singleton for general-purpose string-keyed caching.
• packages/core/src/code_assist/setup.ts:
  • Refactored setupUser to use the new CacheService.
  • Centralized caching logic, making the function implementation cleaner and more robust.
• Tests:
  • Added a comprehensive test suite for the new cache utility in cache.test.ts.
  • Consolidated and updated setup.test.ts to verify the new caching integration.

Related Issues

Related to #21310

How to Validate

1. Run npm test -w @google/gemini-cli-core -- src/utils/cache.test.ts
2. Run npm test -w @google/gemini-cli-core -- src/code_assist/setup.test.ts
3. Verify the build with npm run build.

Pre-Merge Checklist

• Added/updated tests (if needed)
• Validated on required platforms/methods:
  • MacOS
    • npm run

[gemini-cli]

Hi @sehoon38, thank you so much for your contribution to Gemini CLI! We really appreciate the time and effort you've put into this.

We're making some updates to our contribution process to improve how we track and review changes. Please take a moment to review our recent discussion post: Improving Our Contribution Process & Introducing New Guidelines.

Key Update: Starting January 26, 2026, the Gemini CLI project will require all pull requests to be associated with an existing issue. Any pull requests not linked to an issue by that date will be automatically closed.

Thank you for your understanding and for being a part of our community!

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the core library by introducing a generic and robust caching service. This service provides efficient in-memory data storage with features like time-to-live expiration and intelligent handling of asynchronous operations. Its integration into the setupUser function streamlines user data retrieval, leading to improved performance, cleaner code, and better maintainability across the project.

Highlights

• Generic CacheService Implementation: A new, type-safe CacheService has been introduced in the core package, offering flexible in-memory caching with support for both Map and WeakMap backends.
• Time-To-Live (TTL) Support: The CacheService includes configurable Time-To-Live (TTL) functionality, allowing cache entries to automatically expire after a specified duration.
• Automatic Promise Cleanup: The CacheService now automatically removes promises from the cache if they reject, enabling immediate retries for failed asynchronous operations.
• Refactored setupUser Function: The setupUser function has been refactored to utilize the new CacheService, centralizing caching logic and improving its robustness and performance.
• Comprehensive Testing: New and updated test suites have been added for both the CacheService and the setupUser function, ensuring the reliability and correctness of the new caching mechanisms.

Changelog

• packages/core/src/code_assist/setup.test.ts
  • Updated copyright year to 2026.
  • Removed ChangeAuthRequestedError import.
  • Imported resetUserDataCacheForTesting for test isolation.
  • Consolidated describe blocks for setupUser tests into a single block.
  • Added resetUserDataCacheForTesting() call in beforeEach to ensure test isolation.
  • Introduced new test suites specifically for caching behavior, covering scenarios like cache hits, project ID changes, expiration, and failed promises.
  • Refactored existing tests into existing user and new user describe blocks for better organization.
  • Simplified validation and error handling tests to align with the new caching approach.
• packages/core/src/code_assist/setup.ts
  • Imported createCache from ../utils/cache.js.
  • Implemented userDataCache using createCache with WeakMap storage and a 30-second TTL for setupUser results.
  • Exported resetUserDataCacheForTesting to allow tests to clear the cache.
  • Refactored setupUser to act as a caching wrapper, storing and retrieving UserData promises keyed by AuthClient and projectId.
  • Introduced _doSetupUser as an internal function to encapsulate the original setupUser logic, now called by the caching wrapper.
  • Added logic within the caching wrapper to remove failed promises from the cache, enabling immediate retries.
• packages/core/src/index.ts
  • Exported all contents from the new utils/cache.js module.
• packages/core/src/utils/cache.test.ts
  • Added a new test file for the CacheService.
  • Included tests for basic cache operations: get, set, delete, and clear.
  • Tested Time-To-Live (TTL) and expiration behavior for cache entries.
  • Verified the functionality of the getOrCreate method.
  • Tested promise support, specifically the automatic removal of failed promises from the cache.
  • Confirmed WeakMap storage behavior with object keys.
• packages/core/src/utils/cache.ts
  • Added a new file defining CacheEntry, CacheOptions, and the CacheService class.
  • Implemented CacheService to support configurable storage (Map or WeakMap), defaultTtl, and deleteOnPromiseFailure for promises.
  • Provided get, set, getOrCreate, delete, and clear methods for cache management.
  • Ensured the get method correctly handles TTL expiration.
  • Included logic in the set method to remove failed promises from the cache if deleteOnPromiseFailure is true.
  • Made the clear method throw an error if used with WeakMap storage.
  • Provided a createCache factory function for easy cache instantiation.
  • Exported a globalCache singleton with Map storage and a 5-minute TTL for general-purpose use.

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[gemini-code-assist]

Code Review

This pull request introduces a generic CacheService and refactors setupUser to use it for caching, which is a great improvement for performance and consistency. The changes are well-tested. However, I've identified a critical type-safety issue in the new CacheService API that could lead to silent failures, and an opportunity to simplify the setupUser implementation by better leveraging the new caching utility.

[github-actions]

Size Change: +3.07 kB (+0.01%)

Total Size: 26 MB

Filename	Size	Change
./bundle/gemini.js	25.5 MB	+3.07 kB (+0.01%)

ℹ️ View Unchanged

Filename	Size
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B
./bundle/sandbox-macos-permissive-open.sb	890 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB
./bundle/sandbox-macos-strict-open.sb	4.82 kB
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB

_{compressed-size-action}

[sehoon38]

saved ~300ms