Prettyprint octopus merge message.

Including the current branch in the list of heads being merged
was not a good idea, so drop it.  And shorten the message by
grouping branches and tags together to form a single line.

Signed-off-by: Junio C Hamano <junkio@cox.net>

4 files changed, 99 insertions, 24 deletions

diff --git a/Makefile b/Makefile
index f9ecbef6cb..8a1a06f36a 100644
--- a/Makefile
+++ b/Makefile
@@ -87,7 +87,7 @@ SCRIPT_SH = \
 
 SCRIPT_PERL = \
 	git-archimport.perl git-cvsimport.perl git-relink.perl \
-	git-rename.perl git-shortlog.perl
+	git-rename.perl git-shortlog.perl git-fmt-merge-msg.perl
 
 SCRIPT_PYTHON = \
 	git-merge-recursive.py
diff --git a/git-fmt-merge-msg.perl b/git-fmt-merge-msg.perl
new file mode 100755
index 0000000000..f0f3100eb1
--- /dev/null
+++ b/git-fmt-merge-msg.perl
@@ -0,0 +1,93 @@
+#!/usr/bin/perl -w
+#
+# Copyright (c) 2005 Junio C Hamano
+#
+# Read .git/FETCH_HEAD and make a human readable merge message
+# by grouping branches and tags together to form a single line.
+
+use strict;
+
+my @src;
+my %src;
+sub andjoin {
+	my ($label, $labels, $stuff) = @_;
+	my $l = scalar @$stuff;
+	my $m = '';
+	if ($l == 0) {
+		return ();
+	}
+	if ($l == 1) {
+		$m = "$label$stuff->[0]";
+	}
+	else {
+		$m = ("$labels" .
+		      join (', ', @{$stuff}[0..$l-2]) .
+		      " and $stuff->[-1]");
+	}
+	return ($m);
+}
+
+while (<>) {
+	my ($bname, $tname, $gname, $src);
+	chomp;
+	s/^[0-9a-f]*	//;
+	if (s/ of (.*)$//) {
+		$src = $1;
+	} else {
+		# Pulling HEAD
+		$src = $_;
+		$_ = 'HEAD';
+	}
+	if (! exists $src{$src}) {
+		push @src, $src;
+		$src{$src} = {
+			BRANCH => [],
+			TAG => [],
+			GENERIC => [],
+			# &1 == has HEAD.
+			# &2 == has others.
+			HEAD_STATUS => 0,
+		};
+	}
+	if (/^branch (.*)$/) {
+		push @{$src{$src}{BRANCH}}, $1;
+		$src{$src}{HEAD_STATUS} |= 2;
+	}
+	elsif (/^tag (.*)$/) {
+		push @{$src{$src}{TAG}}, $1;
+		$src{$src}{HEAD_STATUS} |= 2;
+	}
+	elsif (/^HEAD$/) {
+		$src{$src}{HEAD_STATUS} |= 1;
+	}
+	else {
+		push @{$src{$src}{GENERIC}}, $_;
+		$src{$src}{HEAD_STATUS} |= 2;
+	}
+}
+
+my @msg;
+for my $src (@src) {
+	if ($src{$src}{HEAD_STATUS} == 1) {
+		# Only HEAD is fetched, nothing else.
+		push @msg, $src;
+		next;
+	}
+	my @this;
+	if ($src{$src}{HEAD_STATUS} == 3) {
+		# HEAD is fetched among others.
+		push @this, andjoin('', '', ['HEAD']);
+	}
+	push @this, andjoin("branch ", "branches ",
+			   $src{$src}{BRANCH});
+	push @this, andjoin("tag ", "tags ",
+			   $src{$src}{TAG});
+	push @this, andjoin("commit ", "commits ",
+			    $src{$src}{GENERIC});
+	my $this = join(', ', @this);
+	if ($src ne '.') {
+		$this .= " from $src";
+	}
+	push @msg, $this;
+}
+print "Merge ", join("; ", @msg), "\n";
diff --git a/git-octopus.sh b/git-octopus.sh
index 521cc6f361..abc682025e 100755
--- a/git-octopus.sh
+++ b/git-octopus.sh
@@ -27,7 +27,7 @@ test "$(git-diff-index --cached "$head")" = "" ||
 # MRC is the current "merge reference commit"
 # MRT is the current "merge result tree"
 
-MRC=$head MSG= PARENT="-p $head"
+MRC=$head PARENT="-p $head"
 MRT=$(git-write-tree)
 CNT=1 ;# counting our head
 NON_FF_MERGE=0
@@ -44,8 +44,6 @@ do
 
 	CNT=`expr $CNT + 1`
 	PARENT="$PARENT -p $SHA1"
-	MSG="$MSG
-	$REPO"
 
 	if test "$common,$NON_FF_MERGE" = "$MRC,0"
 	then
@@ -84,20 +82,9 @@ case "$CNT" in
 1)
 	echo "No changes."
 	exit 0 ;;
-2)
-	echo "Not an Octopus; making an ordinary commit."
-	MSG="Merge "`expr "$MSG" : '.	\(.*\)'` ; # remove LF and TAB
-	;;
-*)
-	# In an octopus, the original head is just one of the equals,
-	# so we should list it as such.
-	HEAD_LINK=`readlink "$GIT_DIR/HEAD"`
-	MSG="Octopus merge of the following:
-
-	$HEAD_LINK from .$MSG"
-	;;
 esac
-result_commit=$(echo "$MSG" | git-commit-tree $MRT $PARENT)
+result_commit=$(git-fmt-merge-msg <"$GIT_DIR/FETCH_HEAD" |
+		git-commit-tree $MRT $PARENT)
 echo "Committed merge $result_commit"
 echo $result_commit >"$GIT_DIR"/HEAD
 git-diff-tree -p $head $result_commit | git-apply --stat
diff --git a/git-pull.sh b/git-pull.sh
index 8cf39e7f64..e3d11961b0 100755
--- a/git-pull.sh
+++ b/git-pull.sh
@@ -25,10 +25,6 @@ then
 fi
 
 merge_head=$(sed -e 's/	.*//' "$GIT_DIR"/FETCH_HEAD | tr '\012' ' ')
-merge_name=$(
-    perl -e 'print join("; ", map { chomp; s/^[0-9a-f]*	//; $_ } <>)' \
-    "$GIT_DIR"/FETCH_HEAD
-)
 
 case "$merge_head" in
 '')
@@ -41,6 +37,5 @@ case "$merge_head" in
 	;;
 esac
 
-git-resolve \
-	"$(cat "$GIT_DIR"/HEAD)" \
-	$merge_head "Merge $merge_name"
+merge_name=$(git-fmt-merge-msg <"$GIT_DIR/FETCH_HEAD")
+git-resolve "$(cat "$GIT_DIR"/HEAD)" $merge_head "$merge_name"