checkout: implement "-" abbreviation, add docs and tests

diff --git a/t/t4006-diff-mode.sh b/t/t4006-diff-mode.sh
index ab5406dd9f241edee7a6067a1426f0a65076eb10..4e92fce1d00a55cfbc39e55b53f95cc309e96ff2 100755 (executable)
--- a/t/t4006-diff-mode.sh
+++ b/t/t4006-diff-mode.sh
@@ -38,6 +38,6 @@ echo ":100644 100755 X X M    rezrov" >expected
 
 test_expect_success \
     'verify' \
-    'git diff expected check'
+    'test_cmp expected check'
 
 test_done