tree-sitter-analyzer: Instructions file for Claude Code

Ruflo — Claude Code Configuration

Rules

• Do what has been asked; nothing more, nothing less
• NEVER create files unless absolutely necessary — prefer editing existing files
• NEVER create documentation files unless explicitly requested
• NEVER save working files or tests to root — use /src, /tests, /docs, /config, /scripts
• ALWAYS read a file before editing it
• NEVER commit secrets, credentials, or .env files
• Keep files under 500 lines
• Validate input at system boundaries

Test Quality Rules — LOCKED (2026-06-28)

These rules exist because the test suite grew to 1,093 files / 21,000 tests with systematic duplication, coverage-chasing files, and weak assertions that let real bugs through (ref: 2026-06-08 TOON incident, §11). All 5 rules are enforced at pre-commit and CI. Violations block merge.

T-1: No new test files for existing plugins (BLOCKER)

🔒 LOCKED: When adding tests for an existing language plugin or MCP tool, ADD to the existing test_{plugin}.py file. Do NOT create new files.

Banned name patterns — pre-commit will reject any new file matching:

• *_comprehensive*.py
• *_edge_cases*.py
• *_coverage_boost*.py
• *_coverage*.py (unless it is a coverage measurement tool, not a test)
• *_extended*.py
• *_optimized*.py

Why: java grew to 38 test files for 498 lines of code. The root cause was "not sure if I covered it → add another file" without a deletion culture.

Legitimate exception: A new file is allowed ONLY when it tests a genuinely new subsystem (a new subpackage, a new MCP tool, a new CLI command) that has no existing test file. The file name must match the module it tests exactly.

Controlled pure-migration exception (user-approved; tracked: #1376): An oversized existing suite may be split into bounded behavior modules only when all of the following conditions hold:

• A tracking issue explicitly authorizes the migration.
• No original test cases are added, removed, duplicated, or weakened; preserve names, parameters, fixture scopes, markers, and helper dependencies.
• Preserve exact before/after collected nodeid mappings, including class methods and parameter IDs, plus AST comparisons and negative mutation probes.
• AST normalization may cover imports, source positions, real docstring translation, and separately declared UTF-8 corrections, never assertion or test-input data. Existing explicit encoding values must not change.
• Every migrated target and new Python module must be at most 500 lines.
• Shared helpers must be non-test modules, without duplicated production logic or star-imported test re-exports. Update live references and verification-family mappings so the old entry file cannot silently become a partial gate.