Merge branch 'ds/branch-checked-out' into ds/rebase-update-ref

* ds/branch-checked-out:
  branch: drop unused worktrees variable
  fetch: stop passing around unused worktrees variable
  branch: fix branch_checked_out() leaks
  branch: use branch_checked_out() when deleting refs
  fetch: use new branch_checked_out() and add tests
  branch: check for bisects and rebases
  branch: add branch_checked_out() helper

t/t2407-worktree-heads.sh

@@ -0,0 +1,129 @@
+#!/bin/sh
+
+test_description='test operations trying to overwrite refs at worktree HEAD'
+
+TEST_PASSES_SANITIZE_LEAK=true
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit init &&
+	git branch -f fake-1 &&
+	git branch -f fake-2 &&
+
+	for i in 1 2 3 4
+	do
+		test_commit $i &&
+		git branch wt-$i &&
+		git worktree add wt-$i wt-$i || return 1
+	done &&
+
+	# Create a server that updates each branch by one commit
+	git init server &&
+	test_commit -C server initial &&
+	git remote add server ./server &&
+	for i in 1 2 3 4
+	do
+		git -C server checkout -b wt-$i &&
+		test_commit -C server A-$i || return 1
+	done &&
+	for i in 1 2
+	do
+		git -C server checkout -b fake-$i &&
+		test_commit -C server f-$i || return 1
+	done
+'
+
+test_expect_success 'refuse to overwrite: checked out in worktree' '
+	for i in 1 2 3 4
+	do
+		test_must_fail git branch -f wt-$i HEAD 2>err
+		grep "cannot force update the branch" err &&
+
+		test_must_fail git branch -D wt-$i 2>err
+		grep "Cannot delete branch" err || return 1
+	done
+'
+
+test_expect_success 'refuse to overwrite: worktree in bisect' '
+	test_when_finished rm -rf .git/worktrees/wt-*/BISECT_* &&
+
+	touch .git/worktrees/wt-4/BISECT_LOG &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-4/BISECT_START &&
+
+	test_must_fail git branch -f fake-2 HEAD 2>err &&
+	grep "cannot force update the branch '\''fake-2'\'' checked out at.*wt-4" err
+'
+
+test_expect_success 'refuse to overwrite: worktree in rebase' '
+	test_when_finished rm -rf .git/worktrees/wt-*/rebase-merge &&
+
+	mkdir -p .git/worktrees/wt-3/rebase-merge &&
+	touch .git/worktrees/wt-3/rebase-merge/interactive &&
+	echo refs/heads/fake-1 >.git/worktrees/wt-3/rebase-merge/head-name &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-3/rebase-merge/onto &&
+
+	test_must_fail git branch -f fake-1 HEAD 2>err &&
+	grep "cannot force update the branch '\''fake-1'\'' checked out at.*wt-3" err
+'
+
+test_expect_success !SANITIZE_LEAK 'refuse to fetch over ref: checked out' '
+	test_must_fail git fetch server +refs/heads/wt-3:refs/heads/wt-3 2>err &&
+	grep "refusing to fetch into branch '\''refs/heads/wt-3'\''" err &&
+
+	# General fetch into refs/heads/ will fail on first ref,
+	# so use a generic error message check.
+	test_must_fail git fetch server +refs/heads/*:refs/heads/* 2>err &&
+	grep "refusing to fetch into branch" err
+'
+
+test_expect_success !SANITIZE_LEAK 'refuse to fetch over ref: worktree in bisect' '
+	test_when_finished rm -rf .git/worktrees/wt-*/BISECT_* &&
+
+	touch .git/worktrees/wt-4/BISECT_LOG &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-4/BISECT_START &&
+
+	test_must_fail git fetch server +refs/heads/fake-2:refs/heads/fake-2 2>err &&
+	grep "refusing to fetch into branch" err
+'
+
+test_expect_success !SANITIZE_LEAK 'refuse to fetch over ref: worktree in rebase' '
+	test_when_finished rm -rf .git/worktrees/wt-*/rebase-merge &&
+
+	mkdir -p .git/worktrees/wt-4/rebase-merge &&
+	touch .git/worktrees/wt-4/rebase-merge/interactive &&
+	echo refs/heads/fake-1 >.git/worktrees/wt-4/rebase-merge/head-name &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-4/rebase-merge/onto &&
+
+	test_must_fail git fetch server +refs/heads/fake-1:refs/heads/fake-1 2>err &&
+	grep "refusing to fetch into branch" err
+'
+
+test_expect_success 'refuse to overwrite when in error states' '
+	test_when_finished rm -rf .git/worktrees/wt-*/rebase-merge &&
+	test_when_finished rm -rf .git/worktrees/wt-*/BISECT_* &&
+
+	# Both branches are currently under rebase.
+	mkdir -p .git/worktrees/wt-3/rebase-merge &&
+	touch .git/worktrees/wt-3/rebase-merge/interactive &&
+	echo refs/heads/fake-1 >.git/worktrees/wt-3/rebase-merge/head-name &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-3/rebase-merge/onto &&
+	mkdir -p .git/worktrees/wt-4/rebase-merge &&
+	touch .git/worktrees/wt-4/rebase-merge/interactive &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-4/rebase-merge/head-name &&
+	echo refs/heads/fake-1 >.git/worktrees/wt-4/rebase-merge/onto &&
+
+	# Both branches are currently under bisect.
+	touch .git/worktrees/wt-4/BISECT_LOG &&
+	echo refs/heads/fake-2 >.git/worktrees/wt-4/BISECT_START &&
+	touch .git/worktrees/wt-1/BISECT_LOG &&
+	echo refs/heads/fake-1 >.git/worktrees/wt-1/BISECT_START &&
+
+	for i in 1 2
+	do
+		test_must_fail git branch -f fake-$i HEAD 2>err &&
+		grep "cannot force update the branch '\''fake-$i'\'' checked out at" err ||
+			return 1
+	done
+'
+
+test_done