Commits

SafePush/Patronus rejects malformed commit messages, so a bad subject line costs a CI round trip.

Subject line

IDEA-12345 <subject>              # behavioral change — ticket, no subsystem prefix
<label> <subsystem>: <subject>    # clearly non-behavioral change

• A behavioral change needs a YouTrack ticket. If you are unsure whether it is behavioral, it is.
• Labels: tests, cleanup, refactor, docs, format, style, setup, misc.
• Never begin a subject with WIP, fixup!, squash!, or amend!, and never use Conventional Commits (fix(scope): …).

Body

Write a body for every change except a mechanical one (a typo, an import, a format pass). This includes a non-production change. Say why you made the change and what you decided. The diff already shows what changed. Write the body in ASD-STE100 Simplified Technical English, as the repository guide (AGENTS.md, section Writing) defines it. A requested suffix such as IJ-MR-100 goes in its own trailing paragraph.

Safe message input

On POSIX shells, pass a multiline commit message through stdin with -F - and a quoted heredoc:

git commit -F - <<'EOF'
IDEA-12345 concise subject

Explain why the change was made and what was decided.
EOF

On PowerShell, do not pipe a here-string into git commit -F -. Windows PowerShell may add a Unicode BOM to the first line, producing a malformed subject that SafePush rejects. Pass one paragraph per -m argument instead; the same form is safe with git commit --amend:

git commit `
  -m "IDEA-12345 concise subject" `
  -m "Explain why the change was made and what was decided." `
  -m "IJ-MR-100"

After committing or amending from PowerShell, inspect git cat-file commit HEAD and confirm that the subject begins directly with the ticket or label, without an invisible BOM.

Do not stage commit messages in /tmp, /private/tmp, or another path outside the workspace. That can require an extra filesystem-access approval and leaves a plaintext artifact behind. If a reusable draft is genuinely needed, keep it under the repository's gitignored out/ directory, for example out/commit-message.txt.

Before writing

1. git status --short and git diff --stat for scope. Read the full diff only for changes you did not make yourself in this session, and file by file when it is large.
2. One commit does one thing — no cleanup or refactoring mixed into a behavior change. When unsure, split.

Examples

MRI-3589 harden single-flight recursion checks

Track active single-flight computations in coroutine context so recursive
awaits fail fast in both the owning coroutine and child coroutines.

IJ-MR-100

tests cidr: migrate JUnit 5 coverage

Convert remaining JUnit 4 suites under cidr/coverage to JUnit 5.
Parametrized tests now use @MethodSource instead of the Theories runner.

Uncovered case (isolated-commit algorithm, misc triage): 2_Commits.md. Pushing: use the safe-push skill.