fix(stack): Rebase branch in dry-run mode for accurate plan output

[remyduthu]

The dry-run plan was showing stale pre-rebase commit hashes, making its
output inconsistent with actual push. Rebase is now always performed
unless --skip-rebase is explicitly passed.

Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com

[mergify]

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Pull request overview

This PR fixes an issue where the dry-run mode in mergify stack push was showing stale pre-rebase commit hashes, making the plan output inconsistent with what would actually be pushed. The fix ensures that rebase is always performed unless --skip-rebase is explicitly passed, even in dry-run mode.

Changes:

• Modified stack_push() to perform rebase regardless of dry_run flag (only respects skip_rebase flag)
• Added two new test cases to verify rebase behavior in dry-run mode with and without --skip-rebase

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
mergify_cli/stack/push.py	Removed the if not dry_run condition wrapping the rebase logic, so rebase now runs in dry-run mode unless --skip-rebase is set
mergify_cli/tests/stack/test_push.py	Added test_stack_dry_run_rebases() and test_stack_dry_run_skip_rebase() to verify the new behavior

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[sileht]

It's weird to have a dry-run command that changes the git tree.

Instead, we should detect if a rebase is needed or not, or something like this, no?

[jd]

It's not a dry run if you do the rebase.

Pull request has been modified.

[mergify]

Merge Queue Status

Rule: default

---

• ✅ Entered queue — 2026-02-26 09:41 UTC
• ✅ Checks passed · in-place
• ✅ Merged — 2026-02-26 09:41 UTC · at b5eeb6473ed5c4c3cd7a098ff88ebbe7fbd67e27

This pull request spent 5 seconds in the queue, with no time running CI.

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