feat(core): enhance EditTool with intelligent indentation rebasing

[Thomas-Shephard]

Summary

This PR enhances the EditTool by implementing intelligent indentation rebasing and trailing whitespace handling. These improvements ensure that code replacements integrate seamlessly with the existing file's style, even when the AI-proposed code has different indentation levels.

Details

• Added rebaseIndentation to adjust proposed code blocks to match target indentation.
• Added handleTrailingSpaces to prevent double-trailing spaces when the source file already contains them.
• Integrated these utilities into calculateExactReplacement, calculateFlexibleReplacement, and calculateRegexReplacement.
• Added logic to preserve inline suffixes (like comments) when shifting or replacing code blocks.
• Comprehensive test coverage added in edit.test.ts.

Related Issues

Closes #19177

How to Validate

Run the tests:
bash
npm test -w @google/gemini-cli-core -- src/tools/edit.test.ts

All 52 tests should pass.

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 @Thomas-Shephard, 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 EditTool's ability to apply code modifications gracefully. It introduces intelligent indentation rebasing and trailing whitespace management, ensuring that AI-generated code snippets or replacements seamlessly conform to the existing file's formatting and style, thereby improving the overall quality and consistency of automated code changes.

Highlights

• Intelligent Indentation Rebasing: Implemented a new utility function, rebaseIndentation, to dynamically adjust the indentation of replacement code blocks to match the target file's existing style.
• Trailing Whitespace Handling: Added handleTrailingSpaces to prevent the duplication of trailing spaces when a replacement is applied, ensuring cleaner code integration.
• Enhanced Replacement Calculations: Integrated the new indentation and whitespace handling logic into calculateExactReplacement, calculateFlexibleReplacement, and calculateRegexReplacement functions.
• Suffix Preservation: Improved logic to preserve inline suffixes, such as comments, when code blocks are shifted or replaced, maintaining context and readability.
• Comprehensive Test Coverage: Significantly expanded the test suite with new cases to validate the intelligent indentation rebasing, trailing space handling, and multi-line replacement functionalities.

Changelog

• packages/core/src/tools/edit.test.ts
  • Added numerous test cases to validate intelligent indentation rebasing, trailing whitespace handling, multi-line replacements, and suffix preservation across exact, flexible, and regex matching scenarios.
• packages/core/src/tools/edit.ts
  • Introduced rebaseIndentation function to dynamically adjust the indentation of text blocks based on a target.
  • Implemented handleTrailingSpaces to prevent redundant trailing spaces in replacements.
  • Refactored calculateExactReplacement to apply intelligent indentation rebasing and preserve line suffixes.
  • Updated calculateFlexibleReplacement to use rebaseIndentation for new code blocks.
  • Modified calculateRegexReplacement to correctly capture and utilize trailing whitespace and apply the new indentation and trailing space logic.

Activity

• New test cases were added to edit.test.ts to cover the enhanced functionality.
• The pull request addresses and closes issue Enhance EditTool with robust indentation rebasing #19177.
• The changes have been validated on Windows using npm run.

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[gemini-code-assist]

Code Review

This pull request introduces intelligent indentation rebasing and trailing whitespace handling to the EditTool, which is a great enhancement for ensuring AI-generated code edits match the existing file's style. The changes are extensive, touching all three replacement strategies (exact, flexible, and regex) and are backed by a comprehensive new set of tests. However, I found a critical issue in the new implementation of calculateExactReplacement that could lead to incorrect results when performing multiple replacements. My review includes a detailed explanation and a suggested fix for this issue.

[Thomas-Shephard]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces intelligent indentation rebasing and trailing whitespace handling to the EditTool. While these are valuable enhancements, a critical issue has been identified in the calculateExactReplacement function where the new indentation rebasing logic fails for multiple occurrences of a multi-line search string, potentially leading to inconsistent formatting.

[Thomas-Shephard]

/gemini review

[gemini-code-assist]

Code Review

This pull request significantly enhances the EditTool by introducing intelligent indentation rebasing and improving whitespace handling through new rebaseIndentation and handleTrailingSpaces utilities, making the tool more robust in preserving file styling. While the extensive test suite is excellent, a potential issue was identified in the suffix handling logic within calculateExactReplacement that could lead to incorrect indentation. Overall, this is a great improvement to the tool's capabilities.

[Thomas-Shephard]

/gemini review

[gemini-code-assist]

Code Review

This pull request significantly enhances the EditTool by introducing intelligent indentation rebasing and sophisticated handling of trailing whitespace and inline suffixes. The new rebaseIndentation and handleTrailingSpaces utilities are well-designed and have been thoughtfully integrated into all three replacement strategies (exact, flexible, and regex), making code replacements much more robust and style-aware. The logic for preserving suffixes is a great addition that will prevent data loss in common editing scenarios. The accompanying tests are comprehensive and cover a wide range of edge cases, which gives high confidence in the correctness of these complex changes. Overall, this is an excellent improvement to the tool's capabilities.