fix: generate valid Claude Code hook schema (closes #138)

[sebastianbreguel]

Closes #138

Problem

generate_hooks_config() emits a hooks config that Claude Code rejects with schema errors, so code-review-graph install corrupts ~/.claude/settings.json. Three bugs in the same function:

1. PreCommit is not a valid Claude Code hook event → Invalid key in record.
2. Missing inner hooks array wrapper. Each entry must have hooks: [{type: "command", command, timeout}], but the old output put command/timeout directly on the entry → hooks: Expected array, but received undefined (the exact error in the issue for SessionStart).
3. Timeouts in milliseconds instead of seconds. 5000, 3000, 10000 — the PostToolUse hook effectively had an 83-minute timeout.

Verified against the official schema: https://docs.claude.com/en/docs/claude-code/hooks

Fix

Rewrite generate_hooks_config() to match the documented schema:

"PostToolUse": [
  {
    "matcher": "Edit|Write|Bash",
    "hooks": [
      {"type": "command", "command": "code-review-graph update --quiet --skip-flows", "timeout": 5}
    ]
  }
]

• Remove the PreCommit entry (no equivalent Claude Code event; pre-commit behavior belongs in a git hook).
• Wrap PostToolUse and SessionStart handlers in hooks: [{type: "command", ...}].
• Convert timeouts from ms to seconds (5000 → 5, 3000 → 3).

Testing

• test_has_post_tool_use / test_has_session_start updated for the nested structure
• New test_does_not_emit_precommit — regression guard for this issue
• New test_all_commands_wrapped_in_inner_hooks_array — structural invariant
• Full suite: 611 passed, 5 skipped, 0 failed
• ruff check clean

[sebastianbreguel]

@tirth8205 hey! could you review this one too? it fixes the hook schema generation (issue #138)

[tirth8205]

This is a critical correctness fix — the hook schema rewrite looks solid. 4 regression tests, clean approach.

Please rebase on latest main (PR #152 just merged and touches the same skills.py file). Once rebased and CI passes, this is good to merge.

[sebastianbreguel]

@tirth8205 Rebased on latest main, conflicts resolved, CI is green. Ready to merge when you are!

[sebastianbreguel]

@tirth8205 up

[tirth8205]

Closing in favor of #208 which was just merged.

Your PR is very solid — it correctly fixes all three schema bugs (nested hooks array, removes PreCommit, converts timeouts to seconds), has excellent regression tests (test_does_not_emit_precommit and test_all_commands_wrapped_in_inner_hooks_array), and includes a CHANGELOG entry. The test coverage and the link to the official Claude Code docs in the description were particularly helpful.

The reason #208 was chosen over this PR is one feature: #208 restores the pre-commit behavior that was lost when removing the invalid PreCommit hook event. It does this correctly by adding install_git_hook() which writes a real .git/hooks/pre-commit script (with append-to-existing and idempotency support) rather than trying to use a non-existent Claude Code event.

One minor note: this PR keeps timeout: 5000 and timeout: 3000 for PostToolUse and SessionStart respectively. The Claude Code docs state timeouts are in seconds, so these would mean 83-minute and 50-minute timeouts. PR #208 corrects these to 30s and 10s. If you reopen or update this PR, that should be fixed too.

Thank you for the thorough fix and detailed write-up — it was the clearest description of the three bugs.