From 840e23db03bb43148c83f079690aa48eeb33eb81 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 16 Dec 2013 09:43:12 -0600
Subject: [PATCH] shears.sh: support fixup! and squash!

One of the most powerful feature added to the already powerful
interactive rebase was to allow workflows where you *add* commits with
the intention to amend ("fix up") other commits in the topic branch at
a later stage, through "git rebase -i --autosquash". Such commits are
added by crafting special-format commit messages, or by using the
convenient --fixup or --squash options of "git commit".

However, with the garden shears, we side-step the original interactive
rebase, therefore we have to re-implement that very convenient
fixup/squash handling.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 share/msysGit/shears.sh | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/share/msysGit/shears.sh b/share/msysGit/shears.sh
index 6e1ea6d3..a8e6bb97 100755
--- a/share/msysGit/shears.sh
+++ b/share/msysGit/shears.sh
@@ -152,6 +152,11 @@ case " $extra_commands " in
 	;;
 esac
 
+string2regex () {
+	echo "$*" |
+	sed 's/[][\\\/*?]/\\&/g'
+}
+
 ensure_labeled () {
 	for n in "$@"
 	do
@@ -293,6 +298,40 @@ exec git update-ref refs/rewritten/$commit HEAD\\
 ")"
 	done
 
+	lastline=9999
+	while true
+	do
+		fixup="$(echo "$todo" |
+			sed "$lastline,\$d" |
+			grep -n -e '^pick [^ ]* \(fixup\|squash\)!' |
+			tail -n 1)"
+		test -n "$fixup" || break
+
+		linenumber=${fixup%%:*}
+		oneline="${fixup#* }"
+		shortsha1="${oneline%% *}"
+		oneline="${oneline#* }"
+		command=${oneline%%!*}
+		oneline="${oneline#*! }"
+		oneline_regex="^pick [^ ]* $(string2regex "$oneline")\$"
+		targetline="$(echo "$todo" |
+			sed "$linenumber,\$d" |
+			grep -n "$oneline_regex" |
+			tail -n 1)"
+		targetline=${targetline%%:*}
+		if test -n "$targetline"
+		then
+			todo="$(echo "$todo" |
+				sed -e "${linenumber}d" \
+					-e "${targetline}a\\
+$command $shortsha1 $oneline")"
+			lastline=$(($linenumber+1))
+		else
+			echo "UNHANDLED: $oneline" >&2
+			lastline=$(($linenumber))
+		fi
+	done
+
 	todo="$(printf '%s\n\n%s' "$todo" "cleanup $needslabel")"
 	echo "$todo" | uniq
 }
-- 
2.11.4.GIT