Merge branch 'jn/maint-commit-missing-template' into maint

* jn/maint-commit-missing-template:
  commit: error out for missing commit message template

Author: gitster

builtin/commit.c

@@ -634,7 +634,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
 			die_errno("could not read SQUASH_MSG");
 		hook_arg1 = "squash";
-	} else if (template_file && !stat(template_file, &statbuf)) {
+	} else if (template_file) {
 		if (strbuf_read_file(&sb, template_file, 0) < 0)
 			die_errno("could not read '%s'", template_file);
 		hook_arg1 = "template";

t/t7500-commit.sh

@@ -28,13 +28,21 @@ test_expect_success 'a basic commit in an empty tree should succeed' '
 test_expect_success 'nonexistent template file should return error' '
 	echo changes >> foo &&
 	git add foo &&
-	test_must_fail git commit --template "$PWD"/notexist
+	(
+		GIT_EDITOR="echo hello >\"\$1\"" &&
+		export GIT_EDITOR &&
+		test_must_fail git commit --template "$PWD"/notexist
+	)
 '
 
 test_expect_success 'nonexistent template file in config should return error' '
 	git config commit.template "$PWD"/notexist &&
-	test_must_fail git commit &&
-	git config --unset commit.template
+	test_when_finished "git config --unset commit.template" &&
+	(
+		GIT_EDITOR="echo hello >\"\$1\"" &&
+		export GIT_EDITOR &&
+		test_must_fail git commit
+	)
 '
 
 # From now on we'll use a template file that exists.