difftool--helper: Remove use of the GIT_MERGE_TOOL variable

diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index 9bf6c98c54f368dfc837a8c5c374021269f20707..eca51a8fe8090e22f49b3c983a95fe1388be4584 100755 (executable)
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -32,7 +32,6 @@ restore_test_defaults()
        # Restores the test defaults used by several tests
        remove_config_vars
        unset GIT_DIFF_TOOL
-       unset GIT_MERGE_TOOL
        unset GIT_DIFFTOOL_PROMPT
        unset GIT_DIFFTOOL_NO_PROMPT
        git config diff.tool test-tool &&
@@ -107,15 +106,7 @@ test_expect_success 'GIT_DIFF_TOOL overrides' '
        git config diff.tool bogus-tool &&
        git config merge.tool bogus-tool &&
 
-       GIT_MERGE_TOOL=test-tool &&
-       export GIT_MERGE_TOOL &&
-       diff=$(git difftool --no-prompt branch) &&
-       test "$diff" = "branch" &&
-       unset GIT_MERGE_TOOL &&
-
-       GIT_MERGE_TOOL=bogus-tool &&
        GIT_DIFF_TOOL=test-tool &&
-       export GIT_MERGE_TOOL &&
        export GIT_DIFF_TOOL &&
 
        diff=$(git difftool --no-prompt branch) &&