Add unit tests for internal/focus package

[greynewell]

Summary

The focus package had zero test coverage despite being used by both the focus CLI command and the MCP get_graph-adjacent functionality. These tests were added alongside the bug fixes in #68 (relationship type case normalization).

• pathMatches() — exact, suffix, and ./-prefix variants
• extract() — file lookup, imports BFS traversal, function/callee population, CalledBy population, self-call exclusion
• Regression guard: verifies uppercase rel types (DEFINES_FUNCTION, CALLS) produce no results — documents and locks in the fix(focus,find): fix relationship type case, empty CalledBy/Imports, stale API #68 fix
• render() — JSON and markdown output modes

Test plan

• go test ./internal/focus/... — 19 tests, all pass
• go build ./... passes

🤖 Generated with Claude Code

Summary by CodeRabbit

• Tests
  • Expanded test coverage for focus handler functionality to improve code quality and reliability.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 828944ba-3394-48c2-9447-d43c5ba05b00

📥 Commits

Reviewing files that changed from the base of the PR and between 4dad082 and 18b7823.

📒 Files selected for processing (1)

• internal/focus/handler_test.go

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Walkthrough

A new test file was added to comprehensively test the focus handler's internal functions: pathMatches (path matching logic), extract (analyzing code and extracting relationships), and render (outputting JSON and Markdown). The tests cover normal cases, edge cases, and various configurations.

Changes

Cohort / File(s)	Summary
Focus Handler Tests internal/focus/handler_test.go	New 304-line test suite covering pathMatches behavior with various path formats, extract function logic for imports and call relationships (including self-call exclusion), and render output for both JSON and Markdown formats.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• fix(focus,find): fix relationship type case, empty CalledBy/Imports, stale API #68: Directly modified the internal functions (pathMatches, extract, render) that these new tests exercise, so reviewing the tests alongside that PR context would be helpful.

Suggested reviewers

• jonathanpopham

Poem

🔍 A test file arrives with focus so keen,
Pathmatches, extracts, renders so clean,
From JSON to Markdown, no stone left unturned,
Edge cases and callers now fully confirmed! ✨

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch test/focus-handler

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