fix(typescript/prefer-namespace-keyword): skip nested TSModuleDeclarations

[overlookmotel]

Prevent fix replacing text within the module name or block in the case of nested modules.

Before this PR:

Input:

module X.Y.module {
  x = "module";
}

After fix:

namespace X.Y.namespace {
  x = "namespace";
}

Prevent this by exiting early if the TSModuleDeclaration is nested (i.e. Y or module in above example).

Note: I discovered this bug when I replaced early return with unwrap in #15805. IMO it's better to unwrap when you believe the check cannot fail, as the panic may alert us to bugs which may otherwise lie undiscovered.

Side note: The design we have with nested TSModuleDeclarations representing module X.Y.Z {} is pretty unintutive. I'd like to change it if we can.

[overlookmotel]

• perf(linter/typescript): avoid searching source text unless required #15805
• fix(typescript/prefer-namespace-keyword): skip nested TSModuleDeclarations #15806 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15806 will not alter performance

_{Comparing 11-17-fix_typescript_prefer-namespace-keyword_skip_nested_tsmoduledeclaration_s (29ad42f) with main (c167dfa)}

Summary

✅ 4 untouched
⏩ 33 skipped¹

Footnotes

1. 33 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull Request Overview

This PR fixes a bug in the prefer-namespace-keyword rule where nested TSModuleDeclaration nodes were being processed incorrectly, leading to unintended text replacements within module block content.

Key changes:

• Added a parent check to skip nested TSModuleDeclaration nodes (lines 64-68)
• Added a test case demonstrating the fix for dotted module names containing "module" in their content (lines 143-147)

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[overlookmotel]

It's really hard to imagine all the possible ways these kinds of searches can go wrong just by thinking about it. Maybe it'd be better to reduce the slice of text that gets searched. e.g. in this case, only search source text between the start of the TSModuleDeclaration and the start of its id. That would have caught this.

[camc314]

I got worried that:

declare module X.Y.module { x = 'module'; }
declare module X.Y { declare module module { x = 'module'; } }
``

would have the same ast for a second 🙂 

[camc314]

Merge activity

• Nov 18, 12:03 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 18, 12:03 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Nov 18, 12:10 PM UTC: Merged by the Graphite merge queue.