diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index d26312899d..41e6589313 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -213,6 +213,20 @@ _get_comp_words_by_ref ()
 }
 fi
 
+# Fills the COMPREPLY array with prefiltered words without any additional
+# processing.
+# Callers must take care of providing only words that match the current word
+# to be completed and adding any prefix and/or suffix (trailing space!), if
+# necessary.
+# 1: List of newline-separated matching completion words, complete with
+#    prefix and suffix.
+__gitcomp_direct ()
+{
+	local IFS=$'\n'
+
+	COMPREPLY=($1)
+}
+
 __gitcompappend ()
 {
 	local x i=${#COMPREPLY[@]}
@@ -354,18 +368,21 @@ __git_tags ()
 #    Can be the name of a configured remote, a path, or a URL.
 # 2: In addition to local refs, list unique branches from refs/remotes/ for
 #    'git checkout's tracking DWIMery (optional; ignored, if set but empty).
-# 3: Currently ignored.
+# 3: A prefix to be added to each listed ref (optional).
 # 4: List only refs matching this word (optional; list all refs if unset or
 #    empty).
+# 5: A suffix to be appended to each listed ref (optional; ignored, if set
+#    but empty).
 #
 # Use __git_complete_refs() instead.
 __git_refs ()
 {
 	local i hash dir track="${2-}"
 	local list_refs_from=path remote="${1-}"
-	local format refs pfx
-	local cur_="${4-$cur}"
+	local format refs
+	local pfx="${3-}" cur_="${4-$cur}" sfx="${5-}"
 	local match="${4-}"
+	local fer_pfx="${pfx//\%/%%}" # "escape" for-each-ref format specifiers
 
 	__git_find_repo_path
 	dir="$__git_repo_path"
@@ -390,7 +407,8 @@ __git_refs ()
 
 	if [ "$list_refs_from" = path ]; then
 		if [[ "$cur_" == ^* ]]; then
-			pfx="^"
+			pfx="$pfx^"
+			fer_pfx="$fer_pfx^"
 			cur_=${cur_#^}
 			match=${match#^}
 		fi
@@ -405,7 +423,7 @@ __git_refs ()
 				case "$i" in
 				$match*)
 					if [ -e "$dir/$i" ]; then
-						echo $pfx$i
+						echo "$pfx$i$sfx"
 					fi
 					;;
 				esac
@@ -416,13 +434,13 @@ __git_refs ()
 				"refs/remotes/$match*" "refs/remotes/$match*/**")
 			;;
 		esac
-		__git_dir="$dir" __git for-each-ref --format="$pfx%($format)" \
+		__git_dir="$dir" __git for-each-ref --format="$fer_pfx%($format)$sfx" \
 			"${refs[@]}"
 		if [ -n "$track" ]; then
 			# employ the heuristic used by git checkout
 			# Try to find a remote branch that matches the completion word
 			# but only output if the branch name is unique
-			__git for-each-ref --format="%(refname:strip=3)" \
+			__git for-each-ref --format="$fer_pfx%(refname:strip=3)$sfx" \
 				--sort="refname:strip=3" \
 				"refs/remotes/*/$match*" "refs/remotes/*/$match*/**" | \
 			uniq -u
@@ -435,16 +453,16 @@ __git_refs ()
 		while read -r hash i; do
 			case "$i" in
 			*^{}) ;;
-			*) echo "$i" ;;
+			*) echo "$pfx$i$sfx" ;;
 			esac
 		done
 		;;
 	*)
 		if [ "$list_refs_from" = remote ]; then
 			case "HEAD" in
-			$match*)	echo "HEAD" ;;
+			$match*)	echo "${pfx}HEAD$sfx" ;;
 			esac
-			__git for-each-ref --format="%(refname:strip=3)" \
+			__git for-each-ref --format="$fer_pfx%(refname:strip=3)$sfx" \
 				"refs/remotes/$remote/$match*" \
 				"refs/remotes/$remote/$match*/**"
 		else
@@ -458,8 +476,8 @@ __git_refs ()
 			while read -r hash i; do
 				case "$i" in
 				*^{})	;;
-				refs/*)	echo "${i#refs/*/}" ;;
-				*)	echo "$i" ;;  # symbolic refs
+				refs/*)	echo "$pfx${i#refs/*/}$sfx" ;;
+				*)	echo "$pfx$i$sfx" ;;  # symbolic refs
 				esac
 			done
 		fi
@@ -494,8 +512,7 @@ __git_complete_refs ()
 		shift
 	done
 
-	__gitcomp_nl "$(__git_refs "$remote" "$track" "" "$cur_")" \
-		"$pfx" "$cur_" "$sfx"
+	__gitcomp_direct "$(__git_refs "$remote" "$track" "$pfx" "$cur_" "$sfx")"
 }
 
 # __git_refs2 requires 1 argument (to pass to __git_refs)
@@ -2997,6 +3014,15 @@ if [[ -n ${ZSH_VERSION-} ]]; then
 		esac
 	}
 
+	__gitcomp_direct ()
+	{
+		emulate -L zsh
+
+		local IFS=$'\n'
+		compset -P '*[=:]'
+		compadd -Q -- ${=1} && _ret=0
+	}
+
 	__gitcomp_nl ()
 	{
 		emulate -L zsh
diff --git a/contrib/completion/git-completion.zsh b/contrib/completion/git-completion.zsh
index e25541308a..c3521fbfc4 100644
--- a/contrib/completion/git-completion.zsh
+++ b/contrib/completion/git-completion.zsh
@@ -67,6 +67,15 @@ __gitcomp ()
 	esac
 }
 
+__gitcomp_direct ()
+{
+	emulate -L zsh
+
+	local IFS=$'\n'
+	compset -P '*[=:]'
+	compadd -Q -- ${=1} && _ret=0
+}
+
 __gitcomp_nl ()
 {
 	emulate -L zsh
diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh
index cc9e741f92..5ed28135be 100755
--- a/t/t9902-completion.sh
+++ b/t/t9902-completion.sh
@@ -400,6 +400,22 @@ test_expect_success '__gitdir - remote as argument' '
 	test_cmp expected "$actual"
 '
 
+test_expect_success '__gitcomp_direct - puts everything into COMPREPLY as-is' '
+	sed -e "s/Z$//g" >expected <<-EOF &&
+	with-trailing-space Z
+	without-trailing-spaceZ
+	--option Z
+	--option=Z
+	$invalid_variable_name Z
+	EOF
+	(
+		cur=should_be_ignored &&
+		__gitcomp_direct "$(cat expected)" &&
+		print_comp
+	) &&
+	test_cmp expected out
+'
+
 test_expect_success '__gitcomp - trailing space - options' '
 	test_gitcomp "--re" "--dry-run --reuse-message= --reedit-message=
 		--reset-author" <<-EOF
@@ -961,6 +977,17 @@ test_expect_success 'teardown after filtering matching refs' '
 	git -C otherrepo branch -D matching/branch-in-other
 '
 
+test_expect_success '__git_refs - for-each-ref format specifiers in prefix' '
+	cat >expected <<-EOF &&
+	evil-%%-%42-%(refname)..master
+	EOF
+	(
+		cur="evil-%%-%42-%(refname)..mas" &&
+		__git_refs "" "" "evil-%%-%42-%(refname).." mas >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
 test_expect_success '__git_complete_refs - simple' '
 	sed -e "s/Z$//" >expected <<-EOF &&
 	HEAD Z