Merge branch 'mh/rebase-fixup'

* mh/rebase-fixup:
  rebase -i: Retain user-edited commit messages after squash/fixup conflicts
  t3404: Set up more of the test repo in the "setup" step
  rebase -i: For fixup commands without squashes, do not start editor
  rebase -i: Change function make_squash_message into update_squash_message
  rebase -i: Extract function do_with_author
  rebase -i: Handle the author script all in one place in do_next
  rebase -i: Extract a function "commit_message"
  rebase -i: Simplify commit counting for generated commit messages
  rebase -i: Improve consistency of commit count in generated commit messages
  t3404: Test the commit count in commit messages generated by "rebase -i"
  rebase -i: Introduce a constant AMEND
  rebase -i: Introduce a constant AUTHOR_SCRIPT
  rebase -i: Document how temporary files are used
  rebase -i: Use symbolic constant $MSG consistently
  rebase -i: Use "test -n" instead of "test ! -z"
  rebase -i: Inline expression
  rebase -i: Remove dead code
  rebase -i: Make the condition for an "if" more transparent

2 files changed, 76 insertions, 31 deletions

diff --git a/t/lib-rebase.sh b/t/lib-rebase.sh
index 0db8250c58..2d922ae43c 100644
--- a/t/lib-rebase.sh
+++ b/t/lib-rebase.sh
@@ -2,9 +2,10 @@
 
 # After setting the fake editor with this function, you can
 #
-# - override the commit message with $FAKE_COMMIT_MESSAGE,
+# - override the commit message with $FAKE_COMMIT_MESSAGE
 # - amend the commit message with $FAKE_COMMIT_AMEND
 # - check that non-commit messages have a certain line count with $EXPECT_COUNT
+# - check the commit count in the commit message header with $EXPECT_HEADER_COUNT
 # - rewrite a rebase -i script as directed by $FAKE_LINES.
 #   $FAKE_LINES consists of a sequence of words separated by spaces.
 #   The following word combinations are possible:
@@ -25,6 +26,9 @@ set_fake_editor () {
 	cat >> fake-editor.sh <<\EOF
 case "$1" in
 */COMMIT_EDITMSG)
+	test -z "$EXPECT_HEADER_COUNT" ||
+		test "$EXPECT_HEADER_COUNT" = $(sed -n '1s/^# This is a combination of \(.*\) commits\./\1/p' < "$1") ||
+		exit
 	test -z "$FAKE_COMMIT_MESSAGE" || echo "$FAKE_COMMIT_MESSAGE" > "$1"
 	test -z "$FAKE_COMMIT_AMEND" || echo "$FAKE_COMMIT_AMEND" >> "$1"
 	exit
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index d9382e41d3..4e3513709e 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -14,15 +14,20 @@ that the result still makes sense.
 
 set_fake_editor
 
-# set up two branches like this:
+# Set up the repository like this:
 #
-# A - B - C - D - E     (master)
+#     one - two - three - four (conflict-branch)
+#   /
+# A - B - C - D - E            (master)
+# | \
+# |   F - G - H                (branch1)
+# |     \
+#  \      I                    (branch2)
 #   \
-#     F - G - H         (branch1)
-#       \
-#         I             (branch2)
+#     J - K - L - M            (no-conflict-branch)
 #
-# where A, B, D and G touch the same file.
+# where A, B, D and G all touch file1, and one, two, three, four all
+# touch file "conflict".
 
 test_expect_success 'setup' '
 	test_commit A file1 &&
@@ -36,9 +41,20 @@ test_expect_success 'setup' '
 	test_commit H file5 &&
 	git checkout -b branch2 F &&
 	test_commit I file6
+	git checkout -b conflict-branch A &&
+	for n in one two three four
+	do
+		test_commit $n conflict
+	done &&
+	git checkout -b no-conflict-branch A &&
+	for n in J K L M
+	do
+		test_commit $n file$n
+	done
 '
 
 test_expect_success 'no changes are a nop' '
+	git checkout branch2 &&
 	git rebase -i F &&
 	test "$(git symbolic-ref -q HEAD)" = "refs/heads/branch2" &&
 	test $(git rev-parse I) = $(git rev-parse HEAD)
@@ -97,7 +113,7 @@ cat > expect2 << EOF
 D
 =======
 G
->>>>>>> 91201e5... G
+>>>>>>> 51047de... G
 EOF
 
 test_expect_success 'stop on conflicting pick' '
@@ -135,7 +151,8 @@ test_expect_success 'squash' '
 	test_tick &&
 	GIT_AUTHOR_NAME="Nitfol" git commit -m "nitfol" file7 &&
 	echo "******************************" &&
-	FAKE_LINES="1 squash 2" git rebase -i --onto master HEAD~2 &&
+	FAKE_LINES="1 squash 2" EXPECT_HEADER_COUNT=2 \
+		git rebase -i --onto master HEAD~2 &&
 	test B = $(cat file7) &&
 	test $(git rev-parse HEAD^) = $(git rev-parse master)
 '
@@ -230,22 +247,59 @@ test_expect_success 'verbose flag is heeded, even after --continue' '
 test_expect_success 'multi-squash only fires up editor once' '
 	base=$(git rev-parse HEAD~4) &&
 	FAKE_COMMIT_AMEND="ONCE" FAKE_LINES="1 squash 2 squash 3 squash 4" \
+		EXPECT_HEADER_COUNT=4 \
 		git rebase -i $base &&
 	test $base = $(git rev-parse HEAD^) &&
 	test 1 = $(git show | grep ONCE | wc -l)
 '
 
-test_expect_success 'multi-fixup only fires up editor once' '
+test_expect_success 'multi-fixup does not fire up editor' '
 	git checkout -b multi-fixup E &&
 	base=$(git rev-parse HEAD~4) &&
-	FAKE_COMMIT_AMEND="ONCE" FAKE_LINES="1 fixup 2 fixup 3 fixup 4" \
+	FAKE_COMMIT_AMEND="NEVER" FAKE_LINES="1 fixup 2 fixup 3 fixup 4" \
 		git rebase -i $base &&
 	test $base = $(git rev-parse HEAD^) &&
-	test 1 = $(git show | grep ONCE | wc -l) &&
+	test 0 = $(git show | grep NEVER | wc -l) &&
 	git checkout to-be-rebased &&
 	git branch -D multi-fixup
 '
 
+test_expect_success 'commit message used after conflict' '
+	git checkout -b conflict-fixup conflict-branch &&
+	base=$(git rev-parse HEAD~4) &&
+	(
+		FAKE_LINES="1 fixup 3 fixup 4" &&
+		export FAKE_LINES &&
+		test_must_fail git rebase -i $base
+	) &&
+	echo three > conflict &&
+	git add conflict &&
+	FAKE_COMMIT_AMEND="ONCE" EXPECT_HEADER_COUNT=2 \
+		git rebase --continue &&
+	test $base = $(git rev-parse HEAD^) &&
+	test 1 = $(git show | grep ONCE | wc -l) &&
+	git checkout to-be-rebased &&
+	git branch -D conflict-fixup
+'
+
+test_expect_success 'commit message retained after conflict' '
+	git checkout -b conflict-squash conflict-branch &&
+	base=$(git rev-parse HEAD~4) &&
+	(
+		FAKE_LINES="1 fixup 3 squash 4" &&
+		export FAKE_LINES &&
+		test_must_fail git rebase -i $base
+	) &&
+	echo three > conflict &&
+	git add conflict &&
+	FAKE_COMMIT_AMEND="TWICE" EXPECT_HEADER_COUNT=2 \
+		git rebase --continue &&
+	test $base = $(git rev-parse HEAD^) &&
+	test 2 = $(git show | grep TWICE | wc -l) &&
+	git checkout to-be-rebased &&
+	git branch -D conflict-squash
+'
+
 cat > expect-squash-fixup << EOF
 B
 
@@ -258,6 +312,7 @@ test_expect_success 'squash and fixup generate correct log messages' '
 	git checkout -b squash-fixup E &&
 	base=$(git rev-parse HEAD~4) &&
 	FAKE_COMMIT_AMEND="ONCE" FAKE_LINES="1 fixup 2 squash 3 fixup 4" \
+		EXPECT_HEADER_COUNT=4 \
 		git rebase -i $base &&
 	git cat-file commit HEAD | sed -e 1,/^\$/d > actual-squash-fixup &&
 	test_cmp expect-squash-fixup actual-squash-fixup &&
@@ -290,24 +345,15 @@ test_expect_success 'squash ignores blank lines' '
 '
 
 test_expect_success 'squash works as expected' '
-	for n in one two three four
-	do
-		echo $n >> file$n &&
-		git add file$n &&
-		git commit -m $n
-	done &&
+	git checkout -b squash-works no-conflict-branch &&
 	one=$(git rev-parse HEAD~3) &&
-	FAKE_LINES="1 squash 3 2" git rebase -i HEAD~3 &&
+	FAKE_LINES="1 squash 3 2" EXPECT_HEADER_COUNT=2 \
+		git rebase -i HEAD~3 &&
 	test $one = $(git rev-parse HEAD~2)
 '
 
 test_expect_success 'interrupted squash works as expected' '
-	for n in one two three four
-	do
-		echo $n >> conflict &&
-		git add conflict &&
-		git commit -m $n
-	done &&
+	git checkout -b interrupted-squash conflict-branch &&
 	one=$(git rev-parse HEAD~3) &&
 	(
 		FAKE_LINES="1 squash 3 2" &&
@@ -324,12 +370,7 @@ test_expect_success 'interrupted squash works as expected' '
 '
 
 test_expect_success 'interrupted squash works as expected (case 2)' '
-	for n in one two three four
-	do
-		echo $n >> conflict &&
-		git add conflict &&
-		git commit -m $n
-	done &&
+	git checkout -b interrupted-squash2 conflict-branch &&
 	one=$(git rev-parse HEAD~3) &&
 	(
 		FAKE_LINES="3 squash 1 2" &&