feat(linter/plugins): add SourceCode#getLines method

[overlookmotel]

ESLint has an undocumented SourceCode#getLines method. Implement it.

Discovered the existence of this method from conformance tests.

[overlookmotel]

• feat(linter/plugins): add SourceCode#getLines method #17177 👈 (View in Graphite)
• main

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[overlookmotel]

Merge activity

• Dec 20, 1:48 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 20, 1:52 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Dec 20, 1:58 PM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull request overview

This PR implements the SourceCode#getLines method, an undocumented ESLint API discovered through conformance tests. The method returns the source text split into lines according to the ECMAScript specification's definition of line breaks.

• Adds the getLines() method to the SOURCE_CODE object which lazily initializes and returns the lines array
• Updates test fixture to verify the method works correctly
• Fixes all 11 failing tests for the no-tabs ESLint rule

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
apps/oxlint/src-js/plugins/source_code.ts	Adds the getLines() method implementation with proper documentation and lazy initialization
apps/oxlint/test/fixtures/sourceCode/plugin.ts	Adds test assertion to verify getLines() returns the expected lines array
apps/oxlint/conformance/snapshot.md	Updates conformance test statistics showing 11 new passing tests and removes the no-tabs rule from the failing section

The implementation looks correct and follows the established patterns in the codebase. The getLines() method properly:

• Lazily initializes the lines array by checking if it's empty and calling initLines() if needed
• Returns the shared lines array (matching the pattern used by properties like lineStartIndices)
• Includes clear JSDoc documentation

No issues were identified in this pull request.

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