fix(js): ingest mjs cjs mts cts module extension variants

[vitali87]

Found dogfooding the flow edges: files with the .mjs, .cjs, .mts, and .cts extensions were not parsed at all. JS_EXTENSIONS stopped at .js/.jsx and TS_EXTENSIONS at .ts, so whole ESM packages, dual-package libraries, and modern config files (eslint.config.mjs and friends) were invisible to the graph: no Module or Function nodes, no CALLS, no IMPORTS, no IO or flow edges. The extensions were already listed in JS_TS_MODULE_EXTENSIONS for tsconfig path stripping, which made the gap easy to miss.

What changed

• JS_EXTENSIONS gains .mjs/.cjs, TS_EXTENSIONS gains .mts/.cts, and JS_TS_ALL_EXTENSIONS covers all eight, so extensionless relative imports (import './util') also probe the new candidates during module resolution.
• JS_TS_MODULE_EXTENSIONS gains .mts/.cts so tsconfig path targets strip them like the rest.

Tests

RED first (46f7c7a): four failing specs covering .mjs and .cjs function/call ingestion, .mts/.cts TypeScript variants, and extensionless import resolution to a .mjs file. GREEN in 8089173. Full suite: 5214 passed.

[gemini-code-assist]

Code Review

This pull request adds support for additional JavaScript and TypeScript file extensions (.mjs, .cjs, .mts, and .cts) across the codebase, updating constants, documentation, and adding corresponding tests. The reviewer suggested adding .d.mts and .d.cts to JS_TS_MODULE_EXTENSIONS to ensure declaration files are correctly resolved and not incorrectly stripped.

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[greptile-apps]

Greptile Summary

This PR adds support for JavaScript and TypeScript module extension variants. The main changes are:

• Adds .mjs and .cjs to JavaScript source discovery.
• Adds .mts and .cts to TypeScript source discovery.
• Extends JS/TS module resolution and tsconfig path stripping for the new variants.
• Adds tests for parsing these files and resolving an extensionless import to .mjs.
• Updates the language support docs and README tables.

Confidence Score: 5/5

Safe to merge with minimal risk.

The change is narrow and centralized around extension constants, docs, and focused tests. No correctness or security issues were identified in the changed paths.

No files require special attention.

T-Rex Logs

What T-Rex did

• The exact pytest invocation for js-module-extension-variants was executed, capturing the working directory and the uv output that revealed a pymgclient build failure with exit code 1.
• A blocker summary was reviewed, showing that the test cannot proceed due to a pymgclient build failure and the absence of a suitable cmake.
• The blocker status was confirmed as blocked based on the summary of the build failure and missing cmake.
• The artifact list was inspected to confirm which artifacts were produced during this validation.

_{Ran code and verified through T-Rex}

Important Files Changed

Filename	Overview
README.md	Updates the supported-language table to document JavaScript and TypeScript module extension variants.
codebase_rag/constants/languages.py	Adds .mjs/.cjs to JavaScript parsing, .mts/.cts to TypeScript parsing, and includes those variants in JS/TS module resolution and tsconfig path stripping.
codebase_rag/tests/test_js_module_extension_variants.py	Adds tests for .mjs, .cjs, .mts, .cts, and extensionless imports resolving to .mjs.
docs/architecture/language-support.md	Updates architecture documentation to list the newly supported JavaScript and TypeScript module extensions.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
A[Source file discovered] --> B{Extension}
B -->|.js .jsx .mjs .cjs| C[JavaScript LanguageSpec]
B -->|.ts .mts .cts| D[TypeScript LanguageSpec]
B -->|.tsx| E[TSX LanguageSpec]
C --> F[Parse functions/imports/calls]
D --> F
E --> F
G[Relative or tsconfig import target] --> H[Strip/probe JS_TS module extensions]
H --> I[Resolve module qualified name]
F --> J[Graph nodes and relationships]

Loading

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flowchart TD
A[Source file discovered] --> B{Extension}
B -->|.js .jsx .mjs .cjs| C[JavaScript LanguageSpec]
B -->|.ts .mts .cts| D[TypeScript LanguageSpec]
B -->|.tsx| E[TSX LanguageSpec]
C --> F[Parse functions/imports/calls]
D --> F
E --> F
G[Relative or tsconfig import target] --> H[Strip/probe JS_TS module extensions]
H --> I[Resolve module qualified name]
F --> J[Graph nodes and relationships]

Loading

_{Reviews (2): Last reviewed commit: "fix(js): strip d.mts and d.cts declarati..." | Re-trigger Greptile}

[vitali87]

@greptile review

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud