could be enabled by running the test suite with correct GIT_TEST_
environment set.
+GIT_TEST_GETTEXT_POISON=<non-empty?> turns all strings marked for
+translation into gibberish if non-empty (think "test -n"). Used for
+spotting those tests that need to be marked with a C_LOCALE_OUTPUT
+prerequisite when adding more strings for translation. See "Testing
+marked strings" in po/README for details.
+
GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole
test suite. Accept any boolean values that are accepted by git-config.
GIT_TEST_PRELOAD_INDEX=<boolean> exercises the preload-index code path
by overriding the minimum number of cache entries required per thread.
+GIT_TEST_REBASE_USE_BUILTIN=<boolean>, when false, disables the
+builtin version of git-rebase. See 'rebase.useBuiltin' in
+git-config(1).
+
GIT_TEST_INDEX_THREADS=<n> enables exercising the multi-threaded loading
of the index for the whole test suite by bypassing the default number of
cache entries and thread minimums. Setting this to 1 will make the