[PATCH 2/2] rebase -i: Preserve whitespace at beginning of commit header in $GIT_EDITOR

[Nazri Ramliy <ayiehere@gmail.com>]

During "git rebase -i", when the commit headers are shown in the editor
for action (pick/squash/etc), the whitespace (if any) at the beginning
of commit headers are stripped out due to the use of "read shortsha1 rest"
for reading the output of "git rev-list".

The missing beginning whitespace do not pose any harm but this could be
annoying when you want to identify these commits to perform actions on,
for example, rewording them to remove the beginning whitespace.

Not having the whitespace makes them hard to spot, and you have to rely
on something like "git log --oneline" to identify them.

This patch:

	1. Ensures that the commit header shown in $GIT_EDITOR is
	   identical to the actual commit header
	2. Add a test for it

Signed-off-by: Nazri Ramliy <ayiehere@gmail.com>
---
This series is based on maint.

Running all test shows no breakage. 

 git-rebase--interactive.sh    |   17 ++++++++++-------
 t/t3404-rebase-interactive.sh |   12 ++++++++++++
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 6b86abc..80991a8 100755
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -683,6 +683,10 @@ parse_onto () {
 	git rev-parse --verify "$1^0"
 }
 
+pick () {
+	git log -1 --abbrev-commit --abbrev=7 --format="pick %h %s" $sha1
+}
+
 while test $# != 0
 do
 	case "$1" in
@@ -887,16 +891,15 @@ first and then run 'git rebase --continue' again."
 			REVISIONS=$ONTO...$HEAD
 			SHORTREVISIONS=$SHORTHEAD
 		fi
-		git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
-			--abbrev=7 --reverse --left-right --topo-order \
-			$REVISIONS | \
-			sed -n "s/^>//p" | while read shortsha1 rest
+
+		git rev-list $MERGES_OPTION --reverse --left-right \
+			--topo-order $REVISIONS | sed -n "s/^>//p" |
+		while read sha1
 		do
 			if test t != "$PRESERVE_MERGES"
 			then
-				echo "pick $shortsha1 $rest" >> "$TODO"
+				pick $sha1 >> "$TODO"
 			else
-				sha1=$(git rev-parse $shortsha1)
 				if test -z "$REBASE_ROOT"
 				then
 					preserve=t
@@ -913,7 +916,7 @@ first and then run 'git rebase --continue' again."
 				if test f = "$preserve"
 				then
 					touch "$REWRITTEN"/$sha1
-					echo "pick $shortsha1 $rest" >> "$TODO"
+					pick $sha1 >> "$TODO"
 				fi
 			fi
 		done
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index ee9a1b2..e346174 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -630,4 +630,16 @@ test_expect_success 'always cherry-pick with --no-ff' '
 	test_cmp empty out
 '
 
+cat >expect_header <<EOF
+  Commit header with beginning whitespace
+EOF
+
+test_expect_success 'preserve whitespace in commit summary' '
+	git checkout -b preserve-whitespace master &&
+	echo a >whitespace_test &&
+	git add whitespace_test &&
+	git commit -m"  Commit header with beginning whitespace" &&
+	EXPECT_HEADER="expect_header" git rebase -i HEAD~1
+'
+
 test_done
-- 
1.7.2.rc2