env-helper: move this built-in to "test-tool env-helper"

Since [1] there has been no reason for keeping "git env--helper" a
built-in. The reason it was a built-in to begin with was to support
the GIT_TEST_GETTEXT_POISON mode removed in that commit. I.e. unlike
the rest of "test-tool" it would potentially be called by the
installed git via "git-sh-i18n.sh".

As none of that applies since [1] we should stop carrying this
technical debt, and move it to t/helper/*. As this mostly move-only
change shows this has the nice bonus that we'll stop wasting time
translating the internal-only strings it emits.

Even though this was a built-in, it was intentionally never
documented, see its introduction in [2]. It never saw use outside of
the test suite, except for the "GIT_TEST_GETTEXT_POISON" use-case
noted above.

1. d162b25f956 (tests: remove support for GIT_TEST_GETTEXT_POISON,
   2021-01-20)
2. b4f207f3394 (env--helper: new undocumented builtin wrapping
   git_env_*(), 2019-06-21)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 2e20a16eb8..ea2672436c 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -22,6 +22,7 @@ int cmd__dump_fsmonitor(int argc, const char **argv);
 int cmd__dump_split_index(int argc, const char **argv);
 int cmd__dump_untracked_cache(int argc, const char **argv);
 int cmd__dump_reftable(int argc, const char **argv);
+int cmd__env_helper(int argc, const char **argv);
 int cmd__example_decorate(int argc, const char **argv);
 int cmd__fast_rebase(int argc, const char **argv);
 int cmd__fsmonitor_client(int argc, const char **argv);