diff: introduce diff.submodule configuration variable

diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index 9c3e997b9d6be69467a78f9ff8b1ff746be8e9b6..eb1d3f85b59b2e74231f0285fc4e90d95d0658fa 100755 (executable)
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -76,6 +76,17 @@ test_expect_success PERL 'custom commands' '
        test "$diff" = "branch"
 '
 
+# Ensures that a custom difftool.<tool>.cmd overrides built-ins
+test_expect_success PERL 'custom commands override built-ins' '
+       restore_test_defaults &&
+       git config difftool.defaults.cmd "cat \$REMOTE" &&
+
+       diff=$(git difftool --tool defaults --no-prompt branch) &&
+       test "$diff" = "master" &&
+
+       git config --unset difftool.defaults.cmd
+'
+
 # Ensures that git-difftool ignores bogus --tool values
 test_expect_success PERL 'difftool ignores bad --tool values' '
        diff=$(git difftool --no-prompt --tool=bad-tool branch)