fix(core): parse raw ASCII buffer strings in Gaxios errors

[sehoon38]

Summary

This PR fixes an issue where raw ASCII buffer strings (comma-separated char codes) were appearing in the Gaxios error response data in development environments. This usually happens when the response is not properly decoded by the library.

Details

The fix involves checking if the error.response.data is a string containing commas. If so, it attempts to parse it as a sequence of character codes and convert it back to a readable string using String.fromCharCode. A safety check using .every((code) => !isNaN(code)) is included to ensure only valid numeric sequences are parsed.

This logic is refactored into a private _parseGaxiosErrorData helper within LoggingContentGenerator.

Related Issues

Closes #20631

How to Validate

Run the tests in packages/core/src/core/loggingContentGenerator.test.ts:

npm test -w @google/gemini-cli-core -- src/core/loggingContentGenerator.test.ts

The "Gaxios error parsing" describe block contains robust tests (using expect(...).rejects) for:

1. Correct parsing of ASCII buffer strings.
2. Leaving non-comma-separated strings alone.
3. Leaving invalid numeric sequences alone.

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:
  • MacOS
    • npm run

[gemini-cli]

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[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.

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[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 resolves an issue where Gaxios error responses in development environments were presenting as raw, comma-separated ASCII character codes instead of human-readable messages. The changes introduce a mechanism to detect and correctly decode these buffer strings, significantly improving the clarity and usability of error messages for developers.

Highlights

• Gaxios Error Parsing: Implemented a fix to correctly parse raw ASCII buffer strings that appear in Gaxios error response data, converting them into readable strings.
• Error Handling Robustness: Added checks to ensure that only valid numeric sequences are parsed, leaving non-comma-separated strings or invalid sequences untouched.
• Test Coverage: Introduced new unit tests to validate the correct parsing of ASCII buffer strings, as well as scenarios where parsing should not occur.

Changelog

• packages/core/src/core/loggingContentGenerator.test.ts
  • Added a new test suite for "Gaxios error parsing".
  • Included a test to verify correct parsing of ASCII buffer strings.
  • Added tests to ensure non-comma-separated strings are not altered.
  • Included a test to confirm that invalid numeric sequences are left as-is.
• packages/core/src/core/loggingContentGenerator.ts
  • Implemented logic within the generateContent method's error handling to detect and parse raw ASCII buffer strings in gError.response.data.
  • Applied the same ASCII buffer string parsing logic to the generateContentStream method's error handling.
  • Added a safety check using .every((code) => !isNaN(code)) to validate character codes before conversion.

Activity

• New tests were added to packages/core/src/core/loggingContentGenerator.test.ts to cover the Gaxios error parsing logic.
• The changes have been validated on MacOS using npm run.

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[gemini-code-assist]

Code Review

This pull request introduces a fix to parse raw ASCII buffer strings from Gaxios errors, which is a good improvement. The implementation correctly handles the conversion and includes relevant tests. My review focuses on improving code maintainability by addressing duplicated logic and enhancing the robustness of the new tests, ensuring they are less fragile.

[github-actions]

Size Change: +763 B (0%)

Total Size: 25.8 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	25.3 MB	+763 B (0%)
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B	0 B
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B
./bundle/sandbox-macos-strict-open.sb	4.82 kB	0 B
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB	0 B

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