Merge branch 'sb/maint-octopus' into maint-1.6.5

* sb/maint-octopus:
  octopus: remove dead code
  octopus: reenable fast-forward merges
  octopus: make merge process simpler to follow

Author: gitster

git-merge-octopus.sh

@@ -44,9 +44,8 @@ esac
 # MRC is the current "merge reference commit"
 # MRT is the current "merge result tree"
 
-MRC=$head MSG= PARENT="-p $head"
+MRC=$(git rev-parse --verify -q $head)
 MRT=$(git write-tree)
-CNT=1 ;# counting our head
 NON_FF_MERGE=0
 OCTOPUS_FAILURE=0
 for SHA1 in $remotes
@@ -61,35 +60,33 @@ do
 		exit 2
 	esac
 
+	eval pretty_name=\${GITHEAD_$SHA1:-$SHA1}
 	common=$(git merge-base --all $SHA1 $MRC) ||
-		die "Unable to find common commit with $SHA1"
+		die "Unable to find common commit with $pretty_name"
 
 	case "$LF$common$LF" in
 	*"$LF$SHA1$LF"*)
-		echo "Already up-to-date with $SHA1"
+		echo "Already up-to-date with $pretty_name"
 		continue
 		;;
 	esac
 
-	CNT=`expr $CNT + 1`
-	PARENT="$PARENT -p $SHA1"
-
 	if test "$common,$NON_FF_MERGE" = "$MRC,0"
 	then
 		# The first head being merged was a fast-forward.
 		# Advance MRC to the head being merged, and use that
 		# tree as the intermediate result of the merge.
 		# We still need to count this as part of the parent set.
 
-		echo "Fast forwarding to: $SHA1"
+		echo "Fast-forwarding to: $pretty_name"
 		git read-tree -u -m $head $SHA1 || exit
 		MRC=$SHA1 MRT=$(git write-tree)
 		continue
 	fi
 
 	NON_FF_MERGE=1
 
-	echo "Trying simple merge with $SHA1"
+	echo "Trying simple merge with $pretty_name"
 	git read-tree -u -m --aggressive  $common $MRT $SHA1 || exit 2
 	next=$(git write-tree 2>/dev/null)
 	if test $? -ne 0

t/t7602-merge-octopus-many.sh

@@ -49,4 +49,55 @@ test_expect_success 'merge c1 with c2, c3, c4, ... c29' '
 	done
 '
 
+cat >expected <<\EOF
+Trying simple merge with c2
+Trying simple merge with c3
+Trying simple merge with c4
+Merge made by octopus.
+ c2.c |    1 +
+ c3.c |    1 +
+ c4.c |    1 +
+ 3 files changed, 3 insertions(+), 0 deletions(-)
+ create mode 100644 c2.c
+ create mode 100644 c3.c
+ create mode 100644 c4.c
+EOF
+
+test_expect_success 'merge output uses pretty names' '
+	git reset --hard c1 &&
+	git merge c2 c3 c4 >actual &&
+	test_cmp actual expected
+'
+
+cat >expected <<\EOF
+Already up-to-date with c4
+Trying simple merge with c5
+Merge made by octopus.
+ c5.c |    1 +
+ 1 files changed, 1 insertions(+), 0 deletions(-)
+ create mode 100644 c5.c
+EOF
+
+test_expect_success 'merge up-to-date output uses pretty names' '
+	git merge c4 c5 >actual &&
+	test_cmp actual expected
+'
+
+cat >expected <<\EOF
+Fast-forwarding to: c1
+Trying simple merge with c2
+Merge made by octopus.
+ c1.c |    1 +
+ c2.c |    1 +
+ 2 files changed, 2 insertions(+), 0 deletions(-)
+ create mode 100644 c1.c
+ create mode 100644 c2.c
+EOF
+
+test_expect_success 'merge fast-forward output uses pretty names' '
+	git reset --hard c0 &&
+	git merge c1 c2 >actual &&
+	test_cmp actual expected
+'
+
 test_done