Merge branch 'sg/bash-prompt'

* sg/bash-prompt:
  bash prompt: mention that PROMPT_COMMAND mode is faster
  bash prompt: avoid command substitution when finalizing gitstring
  bash prompt: avoid command substitution when checking for untracked files
  bash prompt: use bash builtins to check stash state
  bash prompt: use bash builtins to check for unborn branch for dirty state
  bash prompt: combine 'git rev-parse' for detached head
  bash prompt: combine 'git rev-parse' executions in the main code path
  bash prompt: use bash builtins to find out current branch
  bash prompt: use bash builtins to find out rebase state
  bash prompt: run 'git rev-parse --git-dir' directly instead of __gitdir()
  bash prompt: return early from __git_ps1() when not in a git repository
  bash prompt: print unique detached HEAD abbreviated object name
  bash prompt: add a test for symbolic link symbolic refs
  completion, bash prompt: move __gitdir() tests to completion test suite
  bash prompt: use 'write_script' helper in interactive rebase test
  bash prompt: fix redirection coding style in tests

1 files changed, 134 insertions, 0 deletions

diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh
index 81a1657efb..5469dee8d1 100755
--- a/t/t9902-completion.sh
+++ b/t/t9902-completion.sh
@@ -122,6 +122,140 @@ test_gitcomp_nl ()
 
 invalid_variable_name='${foo.bar}'
 
+actual="$TRASH_DIRECTORY/actual"
+
+test_expect_success 'setup for __gitdir tests' '
+	mkdir -p subdir/subsubdir &&
+	git init otherrepo
+'
+
+test_expect_success '__gitdir - from command line (through $__git_dir)' '
+	echo "$TRASH_DIRECTORY/otherrepo/.git" >expected &&
+	(
+		__git_dir="$TRASH_DIRECTORY/otherrepo/.git" &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - repo as argument' '
+	echo "otherrepo/.git" >expected &&
+	__gitdir "otherrepo" >"$actual" &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - remote as argument' '
+	echo "remote" >expected &&
+	__gitdir "remote" >"$actual" &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - .git directory in cwd' '
+	echo ".git" >expected &&
+	__gitdir >"$actual" &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - .git directory in parent' '
+	echo "$(pwd -P)/.git" >expected &&
+	(
+		cd subdir/subsubdir &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - cwd is a .git directory' '
+	echo "." >expected &&
+	(
+		cd .git &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - parent is a .git directory' '
+	echo "$(pwd -P)/.git" >expected &&
+	(
+		cd .git/refs/heads &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - $GIT_DIR set while .git directory in cwd' '
+	echo "$TRASH_DIRECTORY/otherrepo/.git" >expected &&
+	(
+		GIT_DIR="$TRASH_DIRECTORY/otherrepo/.git" &&
+		export GIT_DIR &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - $GIT_DIR set while .git directory in parent' '
+	echo "$TRASH_DIRECTORY/otherrepo/.git" >expected &&
+	(
+		GIT_DIR="$TRASH_DIRECTORY/otherrepo/.git" &&
+		export GIT_DIR &&
+		cd subdir &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - non-existing $GIT_DIR' '
+	(
+		GIT_DIR="$TRASH_DIRECTORY/non-existing" &&
+		export GIT_DIR &&
+		test_must_fail __gitdir
+	)
+'
+
+test_expect_success '__gitdir - gitfile in cwd' '
+	echo "$(pwd -P)/otherrepo/.git" >expected &&
+	echo "gitdir: $TRASH_DIRECTORY/otherrepo/.git" >subdir/.git &&
+	test_when_finished "rm -f subdir/.git" &&
+	(
+		cd subdir &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - gitfile in parent' '
+	echo "$(pwd -P)/otherrepo/.git" >expected &&
+	echo "gitdir: $TRASH_DIRECTORY/otherrepo/.git" >subdir/.git &&
+	test_when_finished "rm -f subdir/.git" &&
+	(
+		cd subdir/subsubdir &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success SYMLINKS '__gitdir - resulting path avoids symlinks' '
+	echo "$(pwd -P)/otherrepo/.git" >expected &&
+	mkdir otherrepo/dir &&
+	test_when_finished "rm -rf otherrepo/dir" &&
+	ln -s otherrepo/dir link &&
+	test_when_finished "rm -f link" &&
+	(
+		cd link &&
+		__gitdir >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success '__gitdir - not a git repository' '
+	(
+		cd subdir/subsubdir &&
+		GIT_CEILING_DIRECTORIES="$TRASH_DIRECTORY" &&
+		export GIT_CEILING_DIRECTORIES &&
+		test_must_fail __gitdir
+	)
+'
+
 test_expect_success '__gitcomp - trailing space - options' '
 	test_gitcomp "--re" "--dry-run --reuse-message= --reedit-message=
 		--reset-author" <<-EOF