[PATCH 0/6] fix hunk editing with 'commit -p -m'

@@ -0,0 +1,37 @@
+#!/bin/sh
+
+test_description='hunk edit with "commit -p -m"'
+. ./test-lib.sh
+
+if ! test_have_prereq PERL
+then
+	skip_all="skipping '$test_description' tests, perl not available"
+	test_done
+fi
+
+test_expect_success 'setup (initial)' '
+	echo line1 >file &&
+	git add file &&
+	git commit -m commit1
+	echo line3 >>file
+'
+
+test_expect_success 'setup expected' '
+cat >expected <<EOF
+diff --git a/file b/file
+index a29bdeb..c0d0fb4 100644
+--- a/file
++++ b/file
+@@ -1 +1,2 @@
+ line1
++line2
+EOF
+'
+
+test_expect_failure 'edit hunk "commit -p -m message"' '
+	echo e | env GIT_EDITOR="sed s/+line3\$/+line2/ -i" git commit -p -m commit2 file &&
+	git diff HEAD^ HEAD >diff &&
+	test_cmp expected diff
+'
+
+test_done

@@ -821,7 +821,7 @@ static void prepare_to_commit(struct commit_list *remoteheads)
 	if (0 < option_edit)
 		strbuf_commented_addf(&msg, _(merge_editor_comment), comment_line_char);
 	write_merge_msg(&msg);
-	if (run_commit_hook(1, get_index_file(), "prepare-commit-msg",
+	if (run_commit_hook(0 < option_edit, get_index_file(), "prepare-commit-msg",
 			    git_path("MERGE_MSG"), "merge", NULL))
 		abort_commit(remoteheads, NULL);
 	if (0 < option_edit) {

@@ -141,7 +141,19 @@ test_expect_success 'with hook (merge)' '
 	git commit -m other &&
 	git checkout - &&
 	git merge other &&
-	test "`git log -1 --pretty=format:%s`" = merge
+	test "`git log -1 --pretty=format:%s`" = "merge (no editor)"
+'
+
+test_expect_success 'with hook and editor (merge)' '
+
+	head=`git rev-parse HEAD` &&
+	git checkout -B other HEAD@{1} &&
+	echo "more" >> file &&
+	git add file &&
+	git commit -m other &&
+	git checkout - &&
+	env GIT_EDITOR="\"\$FAKE_EDITOR\"" git merge -e other &&
+	test "`git log -1 --pretty=format:%s`" = "merge"
 '
 
 cat > "$HOOK" <<'EOF'

@@ -151,6 +163,7 @@ EOF
 
 test_expect_success 'with failing hook' '
 
+	git reset --hard &&
 	head=`git rev-parse HEAD` &&
 	echo "more" >> file &&
 	git add file &&

@@ -160,6 +173,7 @@ test_expect_success 'with failing hook' '
 
 test_expect_success 'with failing hook (--no-verify)' '
 
+	git reset --hard &&
 	head=`git rev-parse HEAD` &&
 	echo "more" >> file &&
 	git add file &&

@@ -169,6 +183,7 @@ test_expect_success 'with failing hook (--no-verify)' '
 
 test_expect_success 'with failing hook (merge)' '
 
+	git reset --hard &&
 	git checkout -B other HEAD@{1} &&
 	echo "more" >> file &&
 	git add file &&

@@ -612,7 +612,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	/* This checks and barfs if author is badly specified */
 	determine_author_info(author_ident);
 
-	if (!no_verify && run_hook(index_file, "pre-commit", NULL))
+	if (!no_verify && run_commit_hook(use_editor, index_file, "pre-commit", NULL))
 		return 0;
 
 	if (squash_message) {

@@ -866,8 +866,8 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		return 0;
 	}
 
-	if (run_hook(index_file, "prepare-commit-msg",
-		     git_path(commit_editmsg), hook_arg1, hook_arg2, NULL))
+	if (run_commit_hook(use_editor, index_file, "prepare-commit-msg",
+			    git_path(commit_editmsg), hook_arg1, hook_arg2, NULL))
 		return 0;
 
 	if (use_editor) {

@@ -883,7 +883,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	}
 
 	if (!no_verify &&
-	    run_hook(index_file, "commit-msg", git_path(commit_editmsg), NULL)) {
+	    run_commit_hook(use_editor, index_file, "commit-msg", git_path(commit_editmsg), NULL)) {
 		return 0;
 	}
 

@@ -1067,8 +1067,6 @@ static int parse_and_validate_options(int argc, const char *argv[],
 		use_editor = 0;
 	if (0 <= edit_flag)
 		use_editor = edit_flag;
-	if (!use_editor)
-		setenv("GIT_EDITOR", ":", 1);
 
 	/* Sanity check options */
 	if (amend && !current_head)

@@ -1445,6 +1443,29 @@ static int run_rewrite_hook(const unsigned char *oldsha1,
 	return finish_command(&proc);
 }
 
+int run_commit_hook(int editor_is_used, const char *index_file, const char *name, ...)
+{
+	const char *hook_env[3] =  { NULL };
+	char index[PATH_MAX];
+	va_list args;
+	int ret;
+
+	snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
+	hook_env[0] = index;
+
+	/*
+	 * Let the hook know that no editor will be launched.
+	 */
+	if (!editor_is_used)
+		hook_env[1] = "GIT_EDITOR=:";
+
+	va_start(args, name);
+	ret = run_hook_v(hook_env, name, args);
+	va_end(args);
+
+	return ret;
+}
+
 int cmd_commit(int argc, const char **argv, const char *prefix)
 {
 	static struct wt_status s;

@@ -1669,7 +1690,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		     "not exceeded, and then \"git reset HEAD\" to recover."));
 
 	rerere(0);
-	run_hook(get_index_file(), "post-commit", NULL);
+	run_commit_hook(use_editor, get_index_file(), "post-commit", NULL);
 	if (amend && !no_post_rewrite) {
 		struct notes_rewrite_cfg *cfg;
 		cfg = init_copy_notes_for_rewrite("amend");

@@ -821,8 +821,8 @@ static void prepare_to_commit(struct commit_list *remoteheads)
 	if (0 < option_edit)
 		strbuf_commented_addf(&msg, _(merge_editor_comment), comment_line_char);
 	write_merge_msg(&msg);
-	if (run_hook(get_index_file(), "prepare-commit-msg",
-		     git_path("MERGE_MSG"), "merge", NULL, NULL))
+	if (run_commit_hook(1, get_index_file(), "prepare-commit-msg",
+			    git_path("MERGE_MSG"), "merge", NULL))
 		abort_commit(remoteheads, NULL);
 	if (0 < option_edit) {
 		if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))

@@ -304,4 +304,7 @@ extern void check_commit_signature(const struct commit* commit, struct signature
 
 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused);
 
+LAST_ARG_MUST_BE_NULL
+extern int run_commit_hook(int editor_is_used, const char *index_file, const char *name, ...);
+
 #endif /* COMMIT_H */

@@ -760,13 +760,11 @@ char *find_hook(const char *name)
 	return path;
 }
 
-int run_hook(const char *index_file, const char *name, ...)
+int run_hook_v(const char *const *env, const char *name, va_list args)
 {
 	struct child_process hook;
 	struct argv_array argv = ARGV_ARRAY_INIT;
-	const char *p, *env[2];
-	char index[PATH_MAX];
-	va_list args;
+	const char *p;
 	int ret;
 
 	p = find_hook(name);

@@ -775,23 +773,28 @@ int run_hook(const char *index_file, const char *name, ...)
 
 	argv_array_push(&argv, p);
 
-	va_start(args, name);
 	while ((p = va_arg(args, const char *)))
 		argv_array_push(&argv, p);
-	va_end(args);
 
 	memset(&hook, 0, sizeof(hook));
 	hook.argv = argv.argv;
+	hook.env = env;
 	hook.no_stdin = 1;
 	hook.stdout_to_stderr = 1;
-	if (index_file) {
-		snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
-		env[0] = index;
-		env[1] = NULL;
-		hook.env = env;
-	}
 
 	ret = run_command(&hook);
 	argv_array_clear(&argv);
 	return ret;
 }
+
+int run_hook(const char *const *env, const char *name, ...)
+{
+	va_list args;
+	int ret;
+
+	va_start(args, name);
+	ret = run_hook_v(env, name, args);
+	va_end(args);
+
+	return ret;
+}

@@ -47,7 +47,8 @@ int run_command(struct child_process *);
 
 extern char *find_hook(const char *name);
 LAST_ARG_MUST_BE_NULL
-extern int run_hook(const char *index_file, const char *name, ...);
+extern int run_hook(const char *const *env, const char *name, ...);
+extern int run_hook_v(const char *const *env, const char *name, va_list args);
 
 #define RUN_COMMAND_NO_STDIN 1
 #define RUN_GIT_CMD	     2	/*If this is to be git sub-command */

@@ -28,7 +28,7 @@ index a29bdeb..c0d0fb4 100644
 EOF
 '
 
-test_expect_failure 'edit hunk "commit -p -m message"' '
+test_expect_success 'edit hunk "commit -p -m message"' '
 	echo e | env GIT_EDITOR="sed s/+line3\$/+line2/ -i" git commit -p -m commit2 file &&
 	git diff HEAD^ HEAD >diff &&
 	test_cmp expected diff

@@ -167,7 +167,7 @@ test_expect_success 'with failing hook' '
 	head=`git rev-parse HEAD` &&
 	echo "more" >> file &&
 	git add file &&
-	! GIT_EDITOR="\"\$FAKE_EDITOR\"" git commit -c $head
+	test_must_fail env GIT_EDITOR="\"\$FAKE_EDITOR\"" git commit -c $head
 
 '
 

@@ -177,7 +177,7 @@ test_expect_success 'with failing hook (--no-verify)' '
 	head=`git rev-parse HEAD` &&
 	echo "more" >> file &&
 	git add file &&
-	! GIT_EDITOR="\"\$FAKE_EDITOR\"" git commit --no-verify -c $head
+	test_must_fail env GIT_EDITOR="\"\$FAKE_EDITOR\"" git commit --no-verify -c $head
 
 '
 

@@ -189,7 +189,7 @@ test_expect_success 'with failing hook (merge)' '
 	git add file &&
 	rm -f "$HOOK" &&
 	git commit -m other &&
-	write_script "$HOOK" <<-EOF
+	write_script "$HOOK" <<-EOF &&
 	exit 1
 	EOF
 	git checkout - &&