rust-lang-rust-pre-push - SKILL.md Agent Skill

name: rust-lang-rust-pre-push description: Pre-push checklist for rust-lang/rust PRs — catches naming, verification, description, and convention issues before they reach reviewers keywords: rust-lang, rust compiler, pre-push, push, before push, submit PR, rust PR, regression test related: rust-lang-rust-tests, pre-pr-review, oss-repo-recon

Pre-Push Checklist for rust-lang/rust

Run this before every git push to rust-lang/rust. Every item here was learned from actual reviewer pushback or CI failures.

1. Local Verification

Run the test with rustc +nightly before committing. Issue reproducers go stale.

# build-pass / check-pass: must exit 0
rustc +nightly [compile-flags] <test-file>.rs 2>&1; echo "Exit: $?"

# Error tests: verify the error matches your .stderr / //~ annotations
rustc +nightly <test-file>.rs 2>&1

If the reproducer doesn't behave as the issue describes, investigate. Don't submit blind.

2. Test File Naming

Scan the test filename. Reject if it matches these patterns:

issue-NNNNN.rs — just an issue number
ice-issue-NNNNN.rs — issue number with generic prefix
Anything where the issue number is the only descriptive content

The name should describe what the test exercises:

# Bad
ice-issue-149035.rs

# Good
generic-const-exprs-mono-collect-ice-149035.rs

3. Test Header

Check the //! header:

First line describes what the test exercises (not "Regression test for...")
Issue link uses full URL in angle brackets: <https://github.com/rust-lang/rust/issues/NNNNN>
No #NNN shorthand issue references (these get flagged by rustbot in commits)

4. Attributes

Check for unnecessary attributes:

No #![allow(incomplete_features)] — compiletest injects -A incomplete_features
No #![allow(dead_code)] or #![allow(unused)] — compiletest injects -A unused for pass tests
#![feature(...)] comes before any remaining #![allow(...)]

5. Directives

Correct test type: build-pass only if ICE was in codegen/linking; check-pass if in analysis
No parenthetical internal reasoning on directives (e.g., //@ check-pass (ICE was in wfcheck, not codegen) — remove the parenthetical)
Directive comments explain why the directive is needed, not why you chose it over alternatives

6. Commit Message

git log --oneline -1

No #NNNNN issue references in the commit message body
No Closes, Fixes, or Resolves keywords — those go in PR body only

7. PR Title

The title should describe what the test exercises, not just reference an issue number:

# Bad
Add regression test for #149035

# Good
Add regression test for mono item collection ICE with generic_const_exprs

8. PR Description

Read it aloud. Check for LLM tells:

No backtick-heavy formatting in prose
No parenthetical explanations after every term
No "this specific scenario", "the test exercises the exact reproducer"
Uses contractions naturally ("didn't", "wasn't", not "was not", "did not")
No bullet-point-heavy structure for simple descriptions
Short — 2-4 sentences max for a regression test PR

9. .stderr Files (if applicable)

Generated from actual rustc +nightly output, not hand-crafted
Line numbers match the final test file (headers shift lines)
$DIR/filename.rs matches the actual filename
LL | replaces line numbers in source display
Warnings suppressed by compiletest (incomplete_features, unused) are NOT in the .stderr