Keep one failure from aborting a batch install

[MikeMcQuaid]

• A bottle that fails to extract aborted the whole brew upgrade (or multi-formula brew install) run, so every remaining formula and cask was skipped: report the failure and carry on with the rest instead, still exiting nonzero.
• Bottle#downloaded_and_valid? trusts an immutable GitHub Packages blob without rehashing it, so a corrupt cached bottle failed to extract on every run. Verify it after a failed extraction, then discard it and retry the extraction with a fresh download.
• brew install and brew reinstall exited as soon as anything had failed, before installing anything at all: install what did download instead, skipping only the packages whose downloads failed.
• Isolate each cask in brew install and each formula in brew reinstall, and widen the errors tolerated per package, so one failure no longer skips everything after it.
• Track which downloads failed in DownloadQueue so a failed bottle only distrusts the shared formula prefetch, rather than also making every already downloaded cask be fetched and verified again.

Fixes #23519.

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Claude Opus 5 high with local review and testing.

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[Copilot]

Pull request overview

This PR improves Homebrew’s batch install/upgrade/reinstall resilience by ensuring that individual package failures (e.g., bottle extraction or download issues) are reported but do not abort the remainder of the run, while still exiting non-zero when any failures occurred.

Changes:

• Continue batch brew upgrade, multi-formula brew install, and brew reinstall after per-formula/cask failures instead of aborting the entire run.
• Add retry behavior for bottles that fail to extract due to a corrupt cached download (rehash after failure, discard if mismatched, redownload once).
• Replace DownloadQueue#fetch_failed with failed_downloads tracking to scope “distrust prefetch” behavior to only the package type that actually failed.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Library/Homebrew/upgrade.rb	Ensures a single formula upgrade failure doesn’t abort subsequent upgrades.
Library/Homebrew/install.rb	Skips installing only formulae whose downloads failed; continues other installs; tolerates per-formula install failures.
Library/Homebrew/bottle.rb	Adds post-extraction-failure checksum verification and a single redownload retry for corrupt cached bottles.
Library/Homebrew/formula_installer.rb	Uses Bottle#stage (with corrupt-cache retry) when pouring bottles outside the download-queue extraction path.
Library/Homebrew/download_queue.rb	Tracks failed_downloads instead of a single boolean, enabling finer-grained retry/skip decisions.
Library/Homebrew/cmd/upgrade.rb	Re-does unprefetched fetch only for the package type that actually failed in shared prefetch.
Library/Homebrew/cmd/reinstall.rb	Continues reinstalling remaining formulae after failures; skips only those whose downloads failed.
Library/Homebrew/cmd/install.rb	Continues installing remaining formulae/casks after individual failures; skips only formulae whose downloads failed.
Library/Homebrew/cask/reinstall.rb	Avoids aborting cask reinstall due to earlier failures in the same run.
Library/Homebrew/test/upgrade_spec.rb	Adds coverage that upgrade reports failure without aborting the batch.
Library/Homebrew/test/install_spec.rb	Adds coverage for skipping only failed-download formulae and continuing installs after an install failure.
Library/Homebrew/test/formula_installer_bottle_spec.rb	Adds coverage for corrupt cached bottle handling during install.
Library/Homebrew/test/download_queue_spec.rb	Updates expectations to validate failed_downloads behavior.
Library/Homebrew/test/cmd/upgrade_spec.rb	Updates queue doubles and adds coverage for scoped distrust of shared prefetch failures.
Library/Homebrew/test/cmd/reinstall_spec.rb	Adds coverage for continuing reinstall after one formula fails.
Library/Homebrew/test/cmd/install_spec.rb	Adds coverage ensuring installs proceed after earlier failures and updates queue doubles.
Library/Homebrew/test/cask/reinstall_spec.rb	Adds coverage that cask reinstall continues after earlier failures in the run.
Library/Homebrew/test/bottle_spec.rb	Adds unit coverage for corrupt cached bottle redownload retry vs. checksum-matching failures.

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[p-linnane]

Nice!

[joshka]

Thanks Mike

[MikeMcQuaid]

@joshka you're welcome, thanks for the good bug report.