Merging upstream version 1:2.45.1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 374 insertions, 84 deletions

diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 13a39eb..75193de 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -122,6 +122,40 @@ __git ()
 		${__git_dir:+--git-dir="$__git_dir"} "$@" 2>/dev/null
 }
 
+# Helper function to read the first line of a file into a variable.
+# __git_eread requires 2 arguments, the file path and the name of the
+# variable, in that order.
+#
+# This is taken from git-prompt.sh.
+__git_eread ()
+{
+	test -r "$1" && IFS=$'\r\n' read -r "$2" <"$1"
+}
+
+# Runs git in $__git_repo_path to determine whether a pseudoref exists.
+# 1: The pseudo-ref to search
+__git_pseudoref_exists ()
+{
+	local ref=$1
+	local head
+
+	__git_find_repo_path
+
+	# If the reftable is in use, we have to shell out to 'git rev-parse'
+	# to determine whether the ref exists instead of looking directly in
+	# the filesystem to determine whether the ref exists. Otherwise, use
+	# Bash builtins since executing Git commands are expensive on some
+	# platforms.
+	if __git_eread "$__git_repo_path/HEAD" head; then
+		if [ "$head" == "ref: refs/heads/.invalid" ]; then
+			__git show-ref --exists "$ref"
+			return $?
+		fi
+	fi
+
+	[ -f "$__git_repo_path/$ref" ]
+}
+
 # Removes backslash escaping, single quotes and double quotes from a word,
 # stores the result in the variable $dequoted_word.
 # 1: The word to dequote.
@@ -420,16 +454,18 @@ fi
 
 # This function is equivalent to
 #
-#    __gitcomp "$(git xxx --git-completion-helper) ..."
+#    ___git_resolved_builtins=$(git xxx --git-completion-helper)
 #
-# except that the output is cached. Accept 1-3 arguments:
+# except that the result of the execution is cached.
+#
+# Accept 1-3 arguments:
 # 1: the git command to execute, this is also the cache key
+#    (use "_" when the command contains spaces, e.g. "remote add"
+#    becomes "remote_add")
 # 2: extra options to be added on top (e.g. negative forms)
 # 3: options to be excluded
-__gitcomp_builtin ()
+__git_resolve_builtins ()
 {
-	# spaces must be replaced with underscore for multi-word
-	# commands, e.g. "git remote add" becomes remote_add.
 	local cmd="$1"
 	local incl="${2-}"
 	local excl="${3-}"
@@ -455,7 +491,24 @@ __gitcomp_builtin ()
 		eval "$var=\"$options\""
 	fi
 
-	__gitcomp "$options"
+	___git_resolved_builtins="$options"
+}
+
+# This function is equivalent to
+#
+#    __gitcomp "$(git xxx --git-completion-helper) ..."
+#
+# except that the output is cached. Accept 1-3 arguments:
+# 1: the git command to execute, this is also the cache key
+#    (use "_" when the command contains spaces, e.g. "remote add"
+#    becomes "remote_add")
+# 2: extra options to be added on top (e.g. negative forms)
+# 3: options to be excluded
+__gitcomp_builtin ()
+{
+	__git_resolve_builtins "$1" "$2" "$3"
+
+	__gitcomp "$___git_resolved_builtins"
 }
 
 # Variation of __gitcomp_nl () that appends to the existing list of
@@ -522,6 +575,26 @@ __gitcomp_file ()
 	true
 }
 
+# Find the current subcommand for commands that follow the syntax:
+#
+#    git <command> <subcommand>
+#
+# 1: List of possible subcommands.
+# 2: Optional subcommand to return when none is found.
+__git_find_subcommand ()
+{
+	local subcommand subcommands="$1" default_subcommand="$2"
+
+	for subcommand in $subcommands; do
+		if [ "$subcommand" = "${words[__git_cmd_idx+1]}" ]; then
+			echo $subcommand
+			return
+		fi
+	done
+
+	echo $default_subcommand
+}
+
 # Execute 'git ls-files', unless the --committable option is specified, in
 # which case it runs 'git diff-index' to find out the files that can be
 # committed.  It return paths relative to the directory specified in the first
@@ -1449,12 +1522,32 @@ _git_bisect ()
 {
 	__git_has_doubledash && return
 
-	local subcommands="start bad good skip reset visualize replay log run"
-	local subcommand="$(__git_find_on_cmdline "$subcommands")"
+	__git_find_repo_path
+
+	# If a bisection is in progress get the terms being used.
+	local term_bad term_good
+	if [ -f "$__git_repo_path"/BISECT_TERMS ]; then
+		term_bad=$(__git bisect terms --term-bad)
+		term_good=$(__git bisect terms --term-good)
+	fi
+
+	# We will complete any custom terms, but still always complete the
+	# more usual bad/new/good/old because git bisect gives a good error
+	# message if these are given when not in use, and that's better than
+	# silent refusal to complete if the user is confused.
+	#
+	# We want to recognize 'view' but not complete it, because it overlaps
+	# with 'visualize' too much and is just an alias for it.
+	#
+	local completable_subcommands="start bad new $term_bad good old $term_good terms skip reset visualize replay log run help"
+	local all_subcommands="$completable_subcommands view"
+
+	local subcommand="$(__git_find_on_cmdline "$all_subcommands")"
+
 	if [ -z "$subcommand" ]; then
 		__git_find_repo_path
 		if [ -f "$__git_repo_path"/BISECT_START ]; then
-			__gitcomp "$subcommands"
+			__gitcomp "$completable_subcommands"
 		else
 			__gitcomp "replay start"
 		fi
@@ -1462,7 +1555,26 @@ _git_bisect ()
 	fi
 
 	case "$subcommand" in
-	bad|good|reset|skip|start)
+	start)
+		case "$cur" in
+		--*)
+			__gitcomp "--first-parent --no-checkout --term-new --term-bad --term-old --term-good"
+			return
+			;;
+		*)
+			__git_complete_refs
+			;;
+		esac
+		;;
+	terms)
+		__gitcomp "--term-good --term-old --term-bad --term-new"
+		return
+		;;
+	visualize|view)
+		__git_complete_log_opts
+		return
+		;;
+	bad|new|"$term_bad"|good|old|"$term_good"|reset|skip)
 		__git_complete_refs
 		;;
 	*)
@@ -1624,8 +1736,7 @@ __git_cherry_pick_inprogress_options=$__git_sequencer_inprogress_options
 
 _git_cherry_pick ()
 {
-	__git_find_repo_path
-	if [ -f "$__git_repo_path"/CHERRY_PICK_HEAD ]; then
+	if __git_pseudoref_exists CHERRY_PICK_HEAD; then
 		__gitcomp "$__git_cherry_pick_inprogress_options"
 		return
 	fi
@@ -1775,7 +1886,7 @@ __git_diff_common_options="--stat --numstat --shortstat --summary
 			--output= --output-indicator-context=
 			--output-indicator-new= --output-indicator-old=
 			--ws-error-highlight=
-			--pickaxe-all --pickaxe-regex
+			--pickaxe-all --pickaxe-regex --patch-with-raw
 "
 
 # Options for diff/difftool
@@ -2039,6 +2150,16 @@ __git_log_common_options="
 	--min-age= --until= --before=
 	--min-parents= --max-parents=
 	--no-min-parents --no-max-parents
+	--alternate-refs --ancestry-path
+	--author-date-order --basic-regexp
+	--bisect --boundary --exclude-first-parent-only
+	--exclude-hidden --extended-regexp
+	--fixed-strings --grep-reflog
+	--ignore-missing --left-only --perl-regexp
+	--reflog --regexp-ignore-case --remove-empty
+	--right-only --show-linear-break
+	--show-notes-by-default --show-pulls
+	--since-as-filter --single-worktree
 "
 # Options that go well for log and gitk (not shortlog)
 __git_log_gitk_options="
@@ -2054,6 +2175,7 @@ __git_log_shortlog_options="
 # Options accepted by log and show
 __git_log_show_options="
 	--diff-merges --diff-merges= --no-diff-merges --dd --remerge-diff
+	--encoding=
 "
 
 __git_diff_merges_opts="off none on first-parent 1 separate m combined c dense-combined cc remerge r"
@@ -2061,13 +2183,15 @@ __git_diff_merges_opts="off none on first-parent 1 separate m combined c dense-c
 __git_log_pretty_formats="oneline short medium full fuller reference email raw format: tformat: mboxrd"
 __git_log_date_formats="relative iso8601 iso8601-strict rfc2822 short local default human raw unix auto: format:"
 
-_git_log ()
+# Complete porcelain (i.e. not git-rev-list) options and at least some
+# option arguments accepted by git-log.  Note that this same set of options
+# are also accepted by some other git commands besides git-log.
+__git_complete_log_opts ()
 {
-	__git_has_doubledash && return
-	__git_find_repo_path
+	COMPREPLY=()
 
 	local merge=""
-	if [ -f "$__git_repo_path/MERGE_HEAD" ]; then
+	if __git_pseudoref_exists MERGE_HEAD; then
 		merge="--merge"
 	fi
 	case "$prev,$cur" in
@@ -2137,6 +2261,8 @@ _git_log ()
 			--no-walk --no-walk= --do-walk
 			--parents --children
 			--expand-tabs --expand-tabs= --no-expand-tabs
+			--clear-decorations --decorate-refs=
+			--decorate-refs-exclude=
 			$merge
 			$__git_diff_common_options
 			"
@@ -2158,6 +2284,16 @@ _git_log ()
 		return
 		;;
 	esac
+}
+
+_git_log ()
+{
+	__git_has_doubledash && return
+	__git_find_repo_path
+
+	__git_complete_log_opts
+        [ ${#COMPREPLY[@]} -eq 0 ] || return
+
 	__git_complete_revlist
 }
 
@@ -2374,13 +2510,30 @@ _git_rebase ()
 
 _git_reflog ()
 {
-	local subcommands="show delete expire"
-	local subcommand="$(__git_find_on_cmdline "$subcommands")"
+	local subcommands subcommand
 
-	if [ -z "$subcommand" ]; then
-		__gitcomp "$subcommands"
-	else
-		__git_complete_refs
+	__git_resolve_builtins "reflog"
+
+	subcommands="$___git_resolved_builtins"
+	subcommand="$(__git_find_subcommand "$subcommands" "show")"
+
+	case "$subcommand,$cur" in
+	show,--*)
+		__gitcomp "
+			$__git_log_common_options
+			"
+		return
+		;;
+	$subcommand,--*)
+		__gitcomp_builtin "reflog_$subcommand"
+		return
+		;;
+	esac
+
+	__git_complete_refs
+
+	if [ $((cword - __git_cmd_idx)) -eq 1 ]; then
+		__gitcompappend "$subcommands" "" "$cur" " "
 	fi
 }
 
@@ -2563,6 +2716,33 @@ __git_compute_config_vars ()
 	__git_config_vars="$(git help --config-for-completion)"
 }
 
+__git_config_vars_all=
+__git_compute_config_vars_all ()
+{
+	test -n "$__git_config_vars_all" ||
+	__git_config_vars_all="$(git --no-pager help --config)"
+}
+
+__git_compute_first_level_config_vars_for_section ()
+{
+	local section="$1"
+	__git_compute_config_vars
+	local this_section="__git_first_level_config_vars_for_section_${section}"
+	test -n "${!this_section}" ||
+	printf -v "__git_first_level_config_vars_for_section_${section}" %s \
+		"$(echo "$__git_config_vars" | awk -F. "/^${section}\.[a-z]/ { print \$2 }")"
+}
+
+__git_compute_second_level_config_vars_for_section ()
+{
+	local section="$1"
+	__git_compute_config_vars_all
+	local this_section="__git_second_level_config_vars_for_section_${section}"
+	test -n "${!this_section}" ||
+	printf -v "__git_second_level_config_vars_for_section_${section}" %s \
+		"$(echo "$__git_config_vars_all" | awk -F. "/^${section}\.</ { print \$3 }")"
+}
+
 __git_config_sections=
 __git_compute_config_sections ()
 {
@@ -2707,73 +2887,50 @@ __git_complete_config_variable_name ()
 	done
 
 	case "$cur_" in
-	branch.*.*)
+	branch.*.*|guitool.*.*|difftool.*.*|man.*.*|mergetool.*.*|remote.*.*|submodule.*.*|url.*.*)
 		local pfx="${cur_%.*}."
 		cur_="${cur_##*.}"
-		__gitcomp "remote pushRemote merge mergeOptions rebase" "$pfx" "$cur_" "$sfx"
+		local section="${pfx%.*.}"
+		__git_compute_second_level_config_vars_for_section "${section}"
+		local this_section="__git_second_level_config_vars_for_section_${section}"
+		__gitcomp "${!this_section}" "$pfx" "$cur_" "$sfx"
 		return
 		;;
 	branch.*)
 		local pfx="${cur_%.*}."
 		cur_="${cur_#*.}"
+		local section="${pfx%.}"
 		__gitcomp_direct "$(__git_heads "$pfx" "$cur_" ".")"
-		__gitcomp_nl_append $'autoSetupMerge\nautoSetupRebase\n' "$pfx" "$cur_" "${sfx- }"
-		return
-		;;
-	guitool.*.*)
-		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "
-			argPrompt cmd confirm needsFile noConsole noRescan
-			prompt revPrompt revUnmerged title
-			" "$pfx" "$cur_" "$sfx"
-		return
-		;;
-	difftool.*.*)
-		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "cmd path" "$pfx" "$cur_" "$sfx"
-		return
-		;;
-	man.*.*)
-		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "cmd path" "$pfx" "$cur_" "$sfx"
-		return
-		;;
-	mergetool.*.*)
-		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "cmd path trustExitCode" "$pfx" "$cur_" "$sfx"
+		__git_compute_first_level_config_vars_for_section "${section}"
+		local this_section="__git_first_level_config_vars_for_section_${section}"
+		__gitcomp_nl_append "${!this_section}" "$pfx" "$cur_" "${sfx:- }"
 		return
 		;;
 	pager.*)
 		local pfx="${cur_%.*}."
 		cur_="${cur_#*.}"
 		__git_compute_all_commands
-		__gitcomp_nl "$__git_all_commands" "$pfx" "$cur_" "${sfx- }"
-		return
-		;;
-	remote.*.*)
-		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "
-			url proxy fetch push mirror skipDefaultUpdate
-			receivepack uploadpack tagOpt pushurl
-			" "$pfx" "$cur_" "$sfx"
+		__gitcomp_nl "$__git_all_commands" "$pfx" "$cur_" "${sfx:- }"
 		return
 		;;
 	remote.*)
 		local pfx="${cur_%.*}."
 		cur_="${cur_#*.}"
+		local section="${pfx%.}"
 		__gitcomp_nl "$(__git_remotes)" "$pfx" "$cur_" "."
-		__gitcomp_nl_append "pushDefault" "$pfx" "$cur_" "${sfx- }"
+		__git_compute_first_level_config_vars_for_section "${section}"
+		local this_section="__git_first_level_config_vars_for_section_${section}"
+		__gitcomp_nl_append "${!this_section}" "$pfx" "$cur_" "${sfx:- }"
 		return
 		;;
-	url.*.*)
+	submodule.*)
 		local pfx="${cur_%.*}."
-		cur_="${cur_##*.}"
-		__gitcomp "insteadOf pushInsteadOf" "$pfx" "$cur_" "$sfx"
+		cur_="${cur_#*.}"
+		local section="${pfx%.}"
+		__gitcomp_nl "$(__git config -f "$(__git rev-parse --show-toplevel)/.gitmodules" --get-regexp 'submodule.*.path' | awk -F. '{print $2}')" "$pfx" "$cur_" "."
+		__git_compute_first_level_config_vars_for_section "${section}"
+		local this_section="__git_first_level_config_vars_for_section_${section}"
+		__gitcomp_nl_append "${!this_section}" "$pfx" "$cur_" "${sfx:- }"
 		return
 		;;
 	*.*)
@@ -2952,7 +3109,7 @@ _git_restore ()
 		__gitcomp_builtin restore
 		;;
 	*)
-		if __git rev-parse --verify --quiet HEAD >/dev/null; then
+		if __git_pseudoref_exists HEAD; then
 			__git_complete_index_file "--modified"
 		fi
 	esac
@@ -2962,8 +3119,7 @@ __git_revert_inprogress_options=$__git_sequencer_inprogress_options
 
 _git_revert ()
 {
-	__git_find_repo_path
-	if [ -f "$__git_repo_path"/REVERT_HEAD ]; then
+	if __git_pseudoref_exists REVERT_HEAD; then
 		__gitcomp "$__git_revert_inprogress_options"
 		return
 	fi
@@ -3084,12 +3240,119 @@ __gitcomp_directories ()
 			COMPREPLY+=("$c/")
 			_found=1
 		fi
-	done < <(git ls-tree -z -d --name-only HEAD $_tmp_dir)
+	done < <(__git ls-tree -z -d --name-only HEAD $_tmp_dir)
 
 	if [[ $_found == 0 ]] && [[ "$cur" =~ /$ ]]; then
 		# No possible further completions any deeper, so assume we're at
 		# a leaf directory and just consider it complete
 		__gitcomp_direct_append "$cur "
+	elif [[ $_found == 0 ]]; then
+		# No possible completions found.  Avoid falling back to
+		# bash's default file and directory completion, because all
+		# valid completions have already been searched and the
+		# fallbacks can do nothing but mislead.  In fact, they can
+		# mislead in three different ways:
+		#    1) Fallback file completion makes no sense when asking
+		#       for directory completions, as this function does.
+		#    2) Fallback directory completion is bad because
+		#       e.g. "/pro" is invalid and should NOT complete to
+		#       "/proc".
+		#    3) Fallback file/directory completion only completes
+		#       on paths that exist in the current working tree,
+		#       i.e. which are *already* part of their
+		#       sparse-checkout.  Thus, normal file and directory
+		#       completion is always useless for "git
+		#       sparse-checkout add" and is also probelmatic for
+		#       "git sparse-checkout set" unless using it to
+		#       strictly narrow the checkout.
+		COMPREPLY=( "" )
+	fi
+}
+
+# In non-cone mode, the arguments to {set,add} are supposed to be
+# patterns, relative to the toplevel directory.  These can be any kind
+# of general pattern, like 'subdir/*.c' and we can't complete on all
+# of those.  However, if the user presses Tab to get tab completion, we
+# presume that they are trying to provide a pattern that names a specific
+# path.
+__gitcomp_slash_leading_paths ()
+{
+	local dequoted_word pfx="" cur_ toplevel
+
+	# Since we are dealing with a sparse-checkout, subdirectories may not
+	# exist in the local working copy.  Therefore, we want to run all
+	# ls-files commands relative to the repository toplevel.
+	toplevel="$(git rev-parse --show-toplevel)/"
+
+	__git_dequote "$cur"
+
+	# If the paths provided by the user already start with '/', then
+	# they are considered relative to the toplevel of the repository
+	# already.  If they do not start with /, then we need to adjust
+	# them to start with the appropriate prefix.
+	case "$cur" in
+	/*)
+		cur="${cur:1}"
+		;;
+	*)
+		pfx="$(__git rev-parse --show-prefix)"
+	esac
+
+	# Since sparse-index is limited to cone-mode, in non-cone-mode the
+	# list of valid paths is precisely the cached files in the index.
+	#
+	# NEEDSWORK:
+	#   1) We probably need to take care of cases where ls-files
+	#      responds with special quoting.
+	#   2) We probably need to take care of cases where ${cur} has
+	#      some kind of special quoting.
+	#   3) On top of any quoting from 1 & 2, we have to provide an extra
+	#      level of quoting for any paths that contain a '*', '?', '\',
+	#      '[', ']', or leading '#' or '!' since those will be
+	#      interpreted by sparse-checkout as something other than a
+	#      literal path character.
+	# Since there are two types of quoting here, this might get really
+	# complex.  For now, just punt on all of this...
+	completions="$(__git -C "${toplevel}" -c core.quotePath=false \
+			 ls-files --cached -- "${pfx}${cur}*" \
+			 | sed -e s%^%/% -e 's%$% %')"
+	# Note, above, though that we needed all of the completions to be
+	# prefixed with a '/', and we want to add a space so that bash
+	# completion will actually complete an entry and let us move on to
+	# the next one.
+
+	# Return what we've found.
+	if test -n "$completions"; then
+		# We found some completions; return them
+		local IFS=$'\n'
+		COMPREPLY=($completions)
+	else
+		# Do NOT fall back to bash-style all-local-files-and-dirs
+		# when we find no match.  Such options are worse than
+		# useless:
+		#     1. "git sparse-checkout add" needs paths that are NOT
+		#        currently in the working copy.  "git
+		#        sparse-checkout set" does as well, except in the
+		#        special cases when users are only trying to narrow
+		#        their sparse checkout to a subset of what they
+		#        already have.
+		#
+		#     2. A path like '.config' is ambiguous as to whether
+		#        the user wants all '.config' files throughout the
+		#        tree, or just the one under the current directory.
+		#        It would result in a warning from the
+		#        sparse-checkout command due to this.  As such, all
+		#        completions of paths should be prefixed with a
+		#        '/'.
+		#
+		#     3. We don't want paths prefixed with a '/' to
+		#        complete files in the system root directory, we
+		#        want it to complete on files relative to the
+		#        repository root.
+		#
+		# As such, make sure that NO completions are offered rather
+		# than falling back to bash's default completions.
+		COMPREPLY=( "" )
 	fi
 }
 
@@ -3097,6 +3360,7 @@ _git_sparse_checkout ()
 {
 	local subcommands="list init set disable add reapply"
 	local subcommand="$(__git_find_on_cmdline "$subcommands")"
+	local using_cone=true
 	if [ -z "$subcommand" ]; then
 		__gitcomp "$subcommands"
 		return
@@ -3107,9 +3371,18 @@ _git_sparse_checkout ()
 		__gitcomp_builtin sparse-checkout_$subcommand "" "--"
 		;;
 	set,*|add,*)
-		if [ "$(__git config core.sparseCheckoutCone)" == "true" ] ||
-		[ -n "$(__git_find_on_cmdline --cone)" ]; then
+		if [[ "$(__git config core.sparseCheckout)" == "true" &&
+		      "$(__git config core.sparseCheckoutCone)" == "false" &&
+		      -z "$(__git_find_on_cmdline --cone)" ]]; then
+			using_cone=false
+		fi
+		if [[ -n "$(__git_find_on_cmdline --no-cone)" ]]; then
+			using_cone=false
+		fi
+		if [[ "$using_cone" == "true" ]]; then
 			__gitcomp_directories
+		else
+			 __gitcomp_slash_leading_paths
 		fi
 	esac
 }
@@ -3356,7 +3629,7 @@ __git_complete_worktree_paths ()
 	# Generate completion reply from worktree list skipping the first
 	# entry: it's the path of the main worktree, which can't be moved,
 	# removed, locked, etc.
-	__gitcomp_nl "$(git worktree list --porcelain |
+	__gitcomp_nl "$(__git worktree list --porcelain |
 		sed -n -e '2,$ s/^worktree //p')"
 }
 
@@ -3592,7 +3865,7 @@ __gitk_main ()
 	__git_find_repo_path
 
 	local merge=""
-	if [ -f "$__git_repo_path/MERGE_HEAD" ]; then
+	if __git_pseudoref_exists MERGE_HEAD; then
 		merge="--merge"
 	fi
 	case "$cur" in
diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index 2c03005..5330e76 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -141,7 +141,7 @@ __git_ps1_show_upstream ()
 
 	# parse configuration values
 	local option
-	for option in ${GIT_PS1_SHOWUPSTREAM}; do
+	for option in ${GIT_PS1_SHOWUPSTREAM-}; do
 		case "$option" in
 		git|svn) upstream_type="$option" ;;
 		verbose) verbose=1 ;;
@@ -408,7 +408,7 @@ __git_ps1 ()
 
 	local repo_info rev_parse_exit_code
 	repo_info="$(git rev-parse --git-dir --is-inside-git-dir \
-		--is-bare-repository --is-inside-work-tree \
+		--is-bare-repository --is-inside-work-tree --show-ref-format \
 		--short HEAD 2>/dev/null)"
 	rev_parse_exit_code="$?"
 
@@ -421,6 +421,8 @@ __git_ps1 ()
 		short_sha="${repo_info##*$'\n'}"
 		repo_info="${repo_info%$'\n'*}"
 	fi
+	local ref_format="${repo_info##*$'\n'}"
+	repo_info="${repo_info%$'\n'*}"
 	local inside_worktree="${repo_info##*$'\n'}"
 	repo_info="${repo_info%$'\n'*}"
 	local bare_repo="${repo_info##*$'\n'}"
@@ -479,12 +481,25 @@ __git_ps1 ()
 			b="$(git symbolic-ref HEAD 2>/dev/null)"
 		else
 			local head=""
-			if ! __git_eread "$g/HEAD" head; then
-				return $exit
-			fi
-			# is it a symbolic ref?
-			b="${head#ref: }"
-			if [ "$head" = "$b" ]; then
+
+			case "$ref_format" in
+			files)
+				if ! __git_eread "$g/HEAD" head; then
+					return $exit
+				fi
+
+				if [[ $head == "ref: "* ]]; then
+					head="${head#ref: }"
+				else
+					head=""
+				fi
+				;;
+			*)
+				head="$(git symbolic-ref HEAD 2>/dev/null)"
+				;;
+			esac
+
+			if test -z "$head"; then
 				detached=yes
 				b="$(
 				case "${GIT_PS1_DESCRIBE_STYLE-}" in
@@ -502,6 +517,8 @@ __git_ps1 ()
 
 				b="$short_sha..."
 				b="($b)"
+			else
+				b="$head"
 			fi
 		fi
 	fi
@@ -511,7 +528,7 @@ __git_ps1 ()
 	fi
 
 	local conflict="" # state indicator for unresolved conflicts
-	if [[ "${GIT_PS1_SHOWCONFLICTSTATE}" == "yes" ]] &&
+	if [[ "${GIT_PS1_SHOWCONFLICTSTATE-}" == "yes" ]] &&
 	   [[ $(git ls-files --unmerged 2>/dev/null) ]]; then
 		conflict="|CONFLICT"
 	fi