test(sdk): add unit tests for GeminiCliSession

[AdamyaSingh7]

Added 16 unit tests covering constructor validation, id getter, initialize() idempotency, and sendStream() behavior for GeminiCliSession in the SDK package.

No prior unit tests existed for this class despite it being the core session abstraction in the public SDK.

Summary

packages/sdk/src/session.ts is the core session class in the public SDK (272 lines) but had zero unit tests. Only integration tests existed in the package. This PR adds a dedicated session.test.ts with 16 unit tests using a mocked Config from @google/gemini-cli-core to avoid heavy filesystem/auth/telemetry setup.

Details

Tests cover 4 areas:

• Constructor validation — accepts string instructions, accepts function instructions, throws with correct message for object/number/array inputs
• id getter — returns correct sessionId, different sessions have different ids
• initialize() — basic init, idempotency (calling twice is safe), works with empty tools/skills arrays, custom model, custom cwd
• sendStream() — auto-initializes if not yet initialized, completes cleanly with no tool calls, accepts an AbortSignal

Mocking pattern follows the existing approach in packages/a2a-server/src/config/config.test.ts.

Related Issues

Fixes #21895

How to Validate

cd packages/sdk
npx vitest run src/session.test.ts

Expected: 16 tests pass, 0 failures.

Pre-Merge Checklist

• Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• Noted breaking changes (if any)
• Validated on required platforms/methods:
  • Windows
    • npm run

[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 robustness of the SDK by introducing comprehensive unit tests for the GeminiCliSession class. Previously lacking dedicated tests, this core session abstraction now has 16 new unit tests covering critical behaviors like constructor validation, session ID retrieval, initialization logic, and stream handling, thereby improving code reliability and maintainability.

Highlights

• Constructor validation: Added tests to ensure GeminiCliSession constructor correctly validates instructions input, accepting strings or functions and throwing errors for invalid types (objects, numbers, arrays).
• id getter: Implemented tests to verify the id getter returns the correct session ID passed during construction and that different sessions have unique IDs.
• initialize() method: Developed tests for the initialize() method, covering successful initialization with string instructions, idempotency (calling multiple times is safe), and proper handling of empty tools/skills arrays, custom models, and custom working directories.
• sendStream() method: Included tests for sendStream(), confirming it auto-initializes if not already initialized, completes cleanly when no tool calls are returned by the model, and correctly accepts an AbortSignal.

Changelog

• packages/sdk/src/session.test.ts
  • Added a new test file containing 16 unit tests for the GeminiCliSession class.

Activity

• AdamyaSingh7 opened this pull request to add unit tests for GeminiCliSession.
• No specific review comments or further activity have been recorded yet.

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[gemini-code-assist]

Code Review

This pull request introduces valuable unit tests for the GeminiCliSession class. The added tests for the constructor, ID getter, and initialize method are well-structured. However, the test suite for the sendStream method is incomplete. I've identified two missing test scenarios for core functionalities—the tool-calling loop and dynamic instructions—that should be added to ensure the robustness of this class.

[gemini-cli]

Hi there! Thank you for your interest in contributing to Gemini CLI.

To ensure we maintain high code quality and focus on our prioritized roadmap, we have updated our contribution policy (see Discussion #17383).

We only guarantee review and consideration of pull requests for issues that are explicitly labeled as 'help wanted'. All other community pull requests are subject to closure after 14 days if they do not align with our current focus areas. For this reason, we strongly recommend that contributors only submit pull requests against issues explicitly labeled as 'help-wanted'.

This pull request is being closed as it has been open for 14 days without a 'help wanted' designation. We encourage you to find and contribute to existing 'help wanted' issues in our backlog! Thank you for your understanding and for being part of our community!

[yunaseoul]

Thanks for contribution. LGTM!