[PATCH 5/6 v5] merge.c: delegate handling of "-" shorthand to revision.c:get_sha1

[Siddharth Kannan <kannan.siddharth12@gmail.com>]

The callchain for handling each argument contains the function
revision.c:get_sha1 where the shorthand for "-" ~ "@{-1}" has already been
implemented in a previous patch; the complete callchain leading to that
function is:

1. merge.c:collect_parents
2. commit.c:get_merge_parent : this function calls revision.c:get_sha1

This patch also adds a test for checking that the shorthand works properly

Signed-off-by: Siddharth Kannan <kannan.siddharth12@gmail.com>
---
 builtin/merge.c                   |  2 --
 t/t3035-merge-hyphen-shorthand.sh | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100755 t/t3035-merge-hyphen-shorthand.sh

diff --git a/builtin/merge.c b/builtin/merge.c
index a96d4fb..36ff420 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -1228,8 +1228,6 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 			argc = setup_with_upstream(&argv);
 		else
 			die(_("No commit specified and merge.defaultToUpstream not set."));
-	} else if (argc == 1 && !strcmp(argv[0], "-")) {
-		argv[0] = "@{-1}";
 	}
 
 	if (!argc)
diff --git a/t/t3035-merge-hyphen-shorthand.sh b/t/t3035-merge-hyphen-shorthand.sh
new file mode 100755
index 0000000..fd37ff9
--- /dev/null
+++ b/t/t3035-merge-hyphen-shorthand.sh
@@ -0,0 +1,33 @@
+#!/bin/sh
+
+test_description='merge uses the shorthand - for @{-1}'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit first &&
+	test_commit second &&
+	test_commit third &&
+	test_commit fourth &&
+	test_commit fifth &&
+	test_commit sixth &&
+	test_commit seventh
+'
+
+test_expect_success 'setup branches' '
+        git checkout master &&
+        git checkout -b testing-2 &&
+        git checkout -b testing-1 &&
+        test_commit eigth &&
+        test_commit ninth
+'
+
+test_expect_success 'merge - should work' '
+        git checkout testing-2 &&
+        git merge - &&
+        git rev-parse HEAD HEAD^^ | sort >actual &&
+        git rev-parse master testing-1 | sort >expect &&
+        test_cmp expect actual
+'
+
+test_done
-- 
2.1.4