branch: delete-merged

Delete branches that have already been merged on upstream.

Changes in v25:

* Wrap long lines in tests.

Changes in v24:

* Map branches through the configured push and fetch refspecs before deciding whether pushing would update their upstream.
* Protect only the direct upstream of surviving work, delete deeper merged bases and clear stale upstream configuration.
* Clarify that --delete-merged takes upstream patterns in docs.

Changes in v23:

* Use a loop-local size_t iterator for --forked patterns.
* Simplify upstream-prefix stripping into an explicit fallback.

Changes in v22:

* Loop variable int when appropriate to avoid typecast.

Changes in v21:

* Change loop variables to prevent CI timeout.

Changes in v20:

* Protect branches transitively required by a surviving local upstream stack. Traverse upstream chains once and defer delete-set mutation until traversal completes.
* Make stacked-branch handling independent of ref iteration order and update the documentation accordingly.
* Clarify variable names with regards to branch names (short) to reduce confusion.

Changes in v19:

* Fix bug where dry-run would still remove config, added test coverage.
* Redesigned --delete-merged as a repeatable upstream selector with optional positional patterns limiting deletion scope.
* Protect same-name upstream branches independently of push-default configuration.
* Simplified flags handling where local caching became complicated when mutating values.
* Clarified assertions in tests.

Changes in v18:

* Instead of keeping the whole chain of upstream branches, keep only the ones an unmerged branch still needs. When a kept (merged) branch in turn tracks a branch that is being deleted, clear its now-stale upstream config.
* Rework spare_stacked_bases() to record the kept bases and, in a second pass, clear the upstream of any whose own base is going away. Build the to-delete list with strset_for_each_entry() instead of re-walking the candidate array.

Changes in v17:

* Keep a merged branch when another surviving branch still tracks it as its upstream, so --delete-merged no longer deletes a branch out from under one stacked on top of it.
* Move the --dry-run and branch.<name>.deleteMerged opt-out fully into their own commits.

Changes in v16:

* Convert delete_merged_branches() to take an unsigned int flags argument instead of separate quiet/dry_run booleans, matching delete_branches()
* Reuse the strbuf across the skip-config loop (strbuf_reset per iteration, single strbuf_release after) instead of allocating and freeing it each time
* Rewrite the --delete-merged tests as integration tests: branches that land commits upstream, with deletion and the checked-out, upstream-gone, and push-equals-upstream safety cases exercised together in one run and output asserted via test_cmp
* Collapse the many per-aspect test repos into a single reused repo set up by a setup_repo_for_delete_merged helper, and rename helpers off the old pm_/prune naming
* Nest single-repo setup sequences in ( cd ... ) subshells instead of prefixing every command with -C

Changes in v15:

* Renamed --prune-merged to --delete-merged throughout. Not necessarily final, but something to advance the discussion.
* --delete-merged now silently skips not-yet-merged branches instead of warning.
* Initialized the delete_branches() flag locals where declared. Only force stays deferred.
* delete_branches()/check_branch_commit() doc and code cleanups: redundant branch NULL checks dropped, ref_array candidates = { 0 }, a BUG() for the unreachable non-branch ref, and reworked --delete-merged doc wording.
* Broadened the --forked tests (local commits for realism, remote add -f, --forked coverage), renamed the misleading trunk fixture, and replaced the misnamed detached branch with git checkout --detach.

Changes in v14:

* Fixed a git branch -d -r regression (broke t5404/t5505/t5514): the remotes path set a local force but not the DELETE_BRANCH_FORCE bit that check_branch_commit() reads, so it wrongly ran the merge check.
* Made flags the single source of truth in delete_branches() so the bit and the derived locals can't disagree.
* Works locally, but GitHub CI has problems that are there for other branches too, hopefully not related
(https://github.com/git/git/pull/2285).

Changes in v13:

* Reworked --forked into a real ref-filter applied in apply_ref_filter() instead of a post-pass, so non-matching branches are never allocated.
* Match exact --forked patterns on full refnames (only globs use the abbreviated upstream), and dropped the old helper machinery, forward declaration, and string_list in favor of a strvec.
* Replaced the boolean parameters of delete_branches()/check_branch_commit() with a single unsigned int flags.
* --prune-merged now collects candidates via filter_refs() rather than its own branch walk.
* --prune-merged now takes its patterns as positional arguments (e.g. git branch --prune-merged origin/main 'feature*') instead of repeating the option.

Changes in v12:

* Reworked --forked from a standalone action into a --list-mode filter.
* Switched --forked and --prune-merged to repeatable OPT_STRING_LIST options.
* Dropped the bare-remote-name resolution for --forked, the argument is now a ref or a glob.

Changes in v11:

* The flags now take a branch, not a remote. --forked and --prune-merged accept a literal upstream short name like origin/main or a wildmatch pattern like origin/. The old --all-remotes flag is gone, since origin/ covers that case.
* The prune guard now compares @{push} against @{upstream}. A branch is spared when these are equal. That is the trunk like case, such as local main tracking and pushing to origin/main, where "fully merged to upstream" cannot be told apart from "just pulled". Only branches that push somewhere other than their upstream, typically fork based topics, are candidates. The earlier /HEAD by name guard that the reviewer rejected is gone.
* New --dry-run for --prune-merged.

Changes in v10:

* --forked / --prune-merged now take a branch glob instead of a remote name — origin, origin/*, origin/release-- all work. This replaces the remote-only form and subsumes the old --all-remotes flag, which has been dropped.
* New --dry-run for --prune-merged.

Changes in v9:

* --force no longer has special meaning with --prune-merged; reachability is always enforced. Use git branch -D to delete an unmerged branch. Matches how git branch's other read/safe actions treat --force.
* Synopsis drops [-f]; "not fully merged" hint points at git branch -D.
* Dropped the --prune-merged --force tests.

Changes in v8:

* Delete only when the branch's work is actually reachable from its upstream
* Skip branches whose upstream is gone (even with --force)
* Simplified the internal safety flag to live in one place

Changes in v7:

* --prune-merged now checks if a branch is merged into its own upstream first. If the upstream is gone, it checks against the remote's default branch instead. If neither exists, the branch is refused (use --force to delete anyway).

Changes in v6:

* --prune-merged now measures merged-ness against the remote's default branch instead of the candidate's upstream — so the decision no longer depends on which branch happens to be checked out locally.
* delete_branches() / check_branch_commit() gained a per-candidate override that lets a caller substitute a different "what counts as merged" reference (or skip the check). branch -d callers pass NULL and keep their existing semantics.
* prune_merged_branches() resolves each candidate's push-remote HEAD and threads it through, so --prune-merged --all-remotes measures each candidate against its own remote rather than a single global reference.

Changes in v5:

* Drop commit 'fetch: add --prune-merged'

Changes in v4:

* Resolve each remote's HEAD and collect the targets into a protected_default_refs set in collect_forked_set.
* In prune_merged_branches, skip a candidate when its upstream is a protected default ref and the local branch name matches the default branch's leaf name (so a local main tracking origin/main is spared, but a renamed trunk tracking origin/main is not).
* Also skip when the candidate's push ref points at a protected default ref, so a topic branch configured to push to origin/main is never pruned.
* Tests: spare the local default branch; only protect by matching leaf name (not by upstream alone); spare a branch whose push ref is the remote default.

Changes in v3:

* s/remote-tracking refs/remote-tracking branches/g

Changes in v2:

* The whole feature moved out of git fetch and into git branch. git fetch --prune-merged now just calls git branch --prune-merged after fetching.
* The fetch.pruneLocalBranches and remote..pruneLocalBranches config options are gone, replaced by per-branch opt-out via branch..pruneMerged.
* New git branch --forked lists local branches whose upstream lives on the given remote (read-only building block).
* New git branch --prune-merged deletes those branches, but only if their tip is reachable from the upstream tracking ref; --force skips that safety check.
* New git branch --all-remotes lets --forked/--prune-merged operate across every configured remote at once.
* The currently checked-out branch in any worktree is always preserved.
* branch..pruneMerged=false lets you exempt a branch (e.g. a long-running topic branch) even with --force; doesn't affect explicit git branch -d.
* delete_branches() got a warn_only mode so bulk deletion prints a one-line warning per skipped branch instead of the noisy four-line hint that git branch -d shows.
* New section in git-branch docs; git-fetch docs trimmed to just mention --prune-merged.
* New tests in t3200-branch.sh for the new branch flags; t5510-fetch.sh shrunk since most logic moved.

Harald Nordgren (7):
branch: add --forked filter for --list mode
branch: convert delete_branches() to a flags argument
branch: let delete_branches skip unmerged branches on bulk refusal
branch: prepare delete_branches for a bulk caller
branch: add --delete-merged <pattern>
branch: add branch.<name>.deleteMerged opt-out
branch: add --dry-run for --delete-merged

 Documentation/config/branch.adoc |   7 +
 Documentation/git-branch.adoc    |  52 +++-
 builtin/branch.c                 | 312 ++++++++++++++++++++---
 ref-filter.c                     |  70 +++++
 ref-filter.h                     |  10 +
 t/t3200-branch.sh                | 421 +++++++++++++++++++++++++++++++
 6 files changed, 841 insertions(+), 31 deletions(-)

base-commit: 5b2471720c93ee30e5764a19f3d3b3ae9ec9712a
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2285%2FHaraldNordgren%2Ffetch-prune-local-branches-v25
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2285/HaraldNordgren/fetch-prune-local-branches-v25
Pull-Request: https://github.com/git/git/pull/2285

Range-diff vs v24:

1: 59157142b3 ! 1: 2f8953b339 branch: add --forked filter for --list mode

     @@ t/t3200-branch.sh: test_expect_success 'errors if given a bad branch name' '
      +'
      +
      +test_expect_success '--forked <upstream-tracking-branch> filters by upstream' '
     -+	git -C forked branch --forked origin/one --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked origin/one \
     ++		--format="%(refname:short)" >actual &&
      +	echo local-one >expect &&
      +	test_cmp expect actual
      +'
      +
      +test_expect_success '--forked <glob> filters by wildmatch' '
     -+	git -C forked branch --forked "origin/*" --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked "origin/*" \
     ++		--format="%(refname:short)" >actual &&
      +	cat >expect <<-\EOF &&
      +	local-one
      +	local-two
     @@ t/t3200-branch.sh: test_expect_success 'errors if given a bad branch name' '
      +'
      +
      +test_expect_success '--forked <local-branch> matches branches with local upstream' '
     -+	git -C forked branch --forked local-base --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked local-base \
     ++		--format="%(refname:short)" >actual &&
      +	echo local-onbase >expect &&
      +	test_cmp expect actual
      +'
      +
      +test_expect_success '--forked can be repeated to widen the filter' '
     -+	git -C forked branch --forked origin/one --forked other/foreign --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked origin/one \
     ++		--forked other/foreign \
     ++		--format="%(refname:short)" >actual &&
      +	cat >expect <<-\EOF &&
      +	local-foreign
      +	local-one
     @@ t/t3200-branch.sh: test_expect_success 'errors if given a bad branch name' '
      +'
      +
      +test_expect_success '--forked combines literal and glob arguments' '
     -+	git -C forked branch --forked local-base --forked "other/*" --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked local-base \
     ++		--forked "other/*" \
     ++		--format="%(refname:short)" >actual &&
      +	cat >expect <<-\EOF &&
      +	local-foreign
      +	local-onbase
     @@ t/t3200-branch.sh: test_expect_success 'errors if given a bad branch name' '
      +'
      +
      +test_expect_success '--forked "*/*" covers every remote-tracking upstream' '
     -+	git -C forked branch --forked "*/*" --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked "*/*" \
     ++		--format="%(refname:short)" >actual &&
      +	cat >expect <<-\EOF &&
      +	local-foreign
      +	local-one
     @@ t/t3200-branch.sh: test_expect_success 'errors if given a bad branch name' '
      +'
      +
      +test_expect_success '--forked composes with --no-merged' '
     -+	git -C forked branch --forked "origin/*" --no-merged origin/one --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked "origin/*" \
     ++		--no-merged origin/one \
     ++		--format="%(refname:short)" >actual &&
      +	echo local-one >expect &&
      +	test_cmp expect actual
      +'
      +
      +test_expect_success '--forked <remote> uses the branch <remote>/HEAD points at' '
     -+	git -C forked branch --forked origin --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked origin \
     ++		--format="%(refname:short)" >actual &&
      +	echo main >expect &&
      +	test_cmp expect actual
      +'
      +
      +test_expect_success '--forked narrows a <pattern> argument' '
     -+	git -C forked branch --forked "origin/*" "local-*" --format="%(refname:short)" >actual &&
     ++	git -C forked branch --forked "origin/*" "local-*" \
     ++		--format="%(refname:short)" >actual &&
      +	cat >expect <<-\EOF &&
      +	local-one
      +	local-two
 2:  5d310da9aa = 2:  2e80fc3791 branch: convert delete_branches() to a flags argument
 3:  263e90f6ed = 3:  4ab81f0b0a branch: let delete_branches skip unmerged branches on bulk refusal
 4:  22e31fd35c = 4:  83cc3fd6a5 branch: prepare delete_branches for a bulk caller
 5:  d9f93e66c9 ! 5:  a5ef60a394 branch: add --delete-merged <pattern>
     @@ t/t3200-branch.sh: test_expect_success '--forked requires a value' '
      +	(
      +		cd repo &&
      +		git checkout -b topic &&
     -+		git config remote.origin.push "refs/heads/topic:refs/heads/published" &&
     ++		git config remote.origin.push \
     ++			"refs/heads/topic:refs/heads/published" &&
      +		git push origin &&
      +		git branch --set-upstream-to=origin/published topic &&
      +		git checkout -b other-topic --track origin/published &&
     @@ t/t3200-branch.sh: test_expect_success '--forked requires a value' '
      +		topic
      +		EOF
      +
     -+		git config --local --get-regexp "branch\\.(feature|topic)\\.(merge|remote)" >actual &&
     ++		pattern="branch\\.(feature|topic)\\.(merge|remote)" &&
     ++		git config --local --get-regexp "$pattern" >actual &&
      +		cat >expect <<-\EOF &&
      +		branch.feature.remote origin
      +		branch.feature.merge refs/heads/next
     @@ t/t3200-branch.sh: test_expect_success '--forked requires a value' '
      +		git commit --allow-empty -m "tip work" &&
      +		sha=$(git rev-parse --short lower) &&
      +
     -+		git branch --delete-merged origin/next --delete-merged lower >actual 2>&1 &&
     ++		git branch --delete-merged origin/next \
     ++			--delete-merged lower >actual 2>&1 &&
      +		echo "Deleted branch lower (was $sha)." >expect &&
      +		test_cmp expect actual &&
      +
     @@ t/t3200-branch.sh: test_expect_success '--forked requires a value' '
      +		tip
      +		EOF
      +
     -+		git config --local --get-regexp "branch\\.(mid|tip)\\.(merge|remote)" >actual &&
     ++		pattern="branch\\.(mid|tip)\\.(merge|remote)" &&
     ++		git config --local --get-regexp "$pattern" >actual &&
      +		cat >expect <<-\EOF &&
      +		branch.tip.remote .
      +		branch.tip.merge refs/heads/mid
     @@ t/t3200-branch.sh: test_expect_success '--forked requires a value' '
      +		main
      +		EOF
      +
     -+		git branch --delete-merged origin/next --delete-merged "c-*" >actual 2>&1 &&
     ++		git branch --delete-merged origin/next \
     ++			--delete-merged "c-*" >actual 2>&1 &&
      +		test_must_be_empty actual &&
      +
      +		check_branches <<-\EOF
 6:  aa845096d8 = 6:  c2d1fdebe8 branch: add branch.<name>.deleteMerged opt-out
 7:  96ebfd6ec6 ! 7:  5a936bcb93 branch: add --dry-run for --delete-merged
     @@ t/t3200-branch.sh: test_expect_success '--delete-merged deletes only selected me
       		git checkout -b tracks-other --track other/main &&
       		sha=$(git rev-parse --short merged) &&
       
     -+		git branch --dry-run --delete-merged origin/next merged >actual 2>&1 &&
     ++		git branch --dry-run --delete-merged origin/next merged \
     ++			>actual 2>&1 &&
      +		echo "Would delete branch merged (was $sha)." >expect &&
      +		test_cmp expect actual &&
      +		git rev-parse --verify refs/heads/merged &&
     @@ t/t3200-branch.sh: test_expect_success '--delete-merged clears the deleted upstr
       		git commit --allow-empty -m "tip work" &&
       		sha=$(git rev-parse --short lower) &&
       
     -+		git branch --dry-run --delete-merged origin/next --delete-merged lower >actual 2>&1 &&
     ++		git branch --dry-run --delete-merged origin/next \
     ++			--delete-merged lower >actual 2>&1 &&
      +		echo "Would delete branch lower (was $sha)." >expect &&
      +		test_cmp expect actual &&
      +
     -+		git config --local --get-regexp "branch\\.(lower|mid|tip)\\.(merge|remote)" >actual &&
     ++		pattern="branch\\.(lower|mid|tip)\\.(merge|remote)" &&
     ++		git config --local --get-regexp "$pattern" >actual &&
      +		cat >expect <<-\EOF &&
      +		branch.lower.remote origin
      +		branch.lower.merge refs/heads/next
     @@ t/t3200-branch.sh: test_expect_success '--delete-merged clears the deleted upstr
      +		EOF
      +		test_cmp expect actual &&
      +
     - 		git branch --delete-merged origin/next --delete-merged lower >actual 2>&1 &&
     + 		git branch --delete-merged origin/next \
     + 			--delete-merged lower >actual 2>&1 &&
       		echo "Deleted branch lower (was $sha)." >expect &&
     - 		test_cmp expect actual &&
      @@ t/t3200-branch.sh: test_expect_success "branch -d still deletes a deleteMerged=false branch" '
       	)
       '

gitgitgadget