Implement automatic fast-forward merge for submodules

diff --git a/t/t4002-diff-basic.sh b/t/t4002-diff-basic.sh
index cc3681f16118ca70ae9f65a27ccd6f354a6deee1..73441a516572dcf826582c04f3fe9d3ad0c1a88c 100755 (executable)
--- a/t/t4002-diff-basic.sh
+++ b/t/t4002-diff-basic.sh
@@ -135,7 +135,7 @@ cmp_diff_files_output () {
     # filesystem.
     sed <"$2" >.test-tmp \
        -e '/^:000000 /d;s/'$x40'\( [MCRNDU][0-9]*\)    /'$z40'\1       /' &&
-    diff "$1" .test-tmp
+    test_cmp "$1" .test-tmp
 }
 
 test_expect_success \
@@ -258,4 +258,12 @@ test_expect_success \
     git diff-tree -r -R $tree_A $tree_B >.test-b &&
     cmp -s .test-a .test-b'
 
+test_expect_success \
+    'diff can read from stdin' \
+    'test_must_fail git diff --no-index -- MN - < NN |
+        grep -v "^index" | sed "s#/-#/NN#" >.test-a &&
+    test_must_fail git diff --no-index -- MN NN |
+        grep -v "^index" >.test-b &&
+    test_cmp .test-a .test-b'
+
 test_done