[PATCH v3 1/5] tests: exercise the RUNTIME_PREFIX feature

From: "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: Ramsay Jones <ramsay@ramsayjones.plus.com>,
	Duy Nguyen <pclouds@gmail.com>,
	Junio C Hamano <gitster@pobox.com>, Johannes Sixt <j6t@kdbg.org>,
	Jeff King <peff@peff.net>,
	Eric Sunshine <sunshine@sunshineco.com>,
	Johannes Schindelin <johannes.schindelin@gmx.de>,
	Johannes Schindelin <johannes.schindelin@gmx.de>
Subject: [PATCH v3 1/5] tests: exercise the RUNTIME_PREFIX feature
Date: Sat, 24 Jul 2021 22:06:49 +0000	[thread overview]
Message-ID: <cc8f09baba94546a13087e923e9c2374284c8136.1627164413.git.gitgitgadget@gmail.com> (raw)
In-Reply-To: <pull.66.v3.git.1627164413.gitgitgadget@gmail.com>

From: Johannes Schindelin <johannes.schindelin@gmx.de>

Originally, we refrained from adding a regression test in 7b6c6496374
(system_path(): Add prefix computation at runtime if RUNTIME_PREFIX set,
2008-08-10), and in 226c0ddd0d6 (exec_cmd: RUNTIME_PREFIX on some POSIX
systems, 2018-04-10).

The reason was that it was deemed too tricky to test.

Turns out that it is not tricky to test at all: we simply create a
pseudo-root, copy the `git` executable into the `git/` subdirectory of
that pseudo-root, then copy a script into the `libexec/git-core/`
directory and expect that to be picked up.

As long as the trash directory is in a location where binaries can be
executed, this works.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile              |  5 +++++
 t/t0060-path-utils.sh | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/Makefile b/Makefile
index c3565fc0f8f..4c3e4ccabcd 100644
--- a/Makefile
+++ b/Makefile
@@ -2826,6 +2826,11 @@ ifdef GIT_TEST_INDEX_VERSION
 endif
 ifdef GIT_TEST_PERL_FATAL_WARNINGS
 	@echo GIT_TEST_PERL_FATAL_WARNINGS=\''$(subst ','\'',$(subst ','\'',$(GIT_TEST_PERL_FATAL_WARNINGS)))'\' >>$@+
+endif
+ifdef RUNTIME_PREFIX
+	@echo RUNTIME_PREFIX=\'true\' >>$@+
+else
+	@echo RUNTIME_PREFIX=\'false\' >>$@+
 endif
 	@if cmp $@+ $@ >/dev/null 2>&1; then $(RM) $@+; else mv $@+ $@; fi
 
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index de4960783f0..a76728c27bf 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -525,4 +525,22 @@ test_expect_success MINGW 'is_valid_path() on Windows' '
 		"PRN./abc"
 '
 
+test_lazy_prereq RUNTIME_PREFIX '
+	test true = "$RUNTIME_PREFIX"
+'
+
+test_lazy_prereq CAN_EXEC_IN_PWD '
+	cp "$GIT_EXEC_PATH"/git$X ./ &&
+	./git rev-parse
+'
+
+test_expect_success RUNTIME_PREFIX,CAN_EXEC_IN_PWD 'RUNTIME_PREFIX works' '
+	mkdir -p pretend/bin pretend/libexec/git-core &&
+	echo "echo HERE" | write_script pretend/libexec/git-core/git-here &&
+	cp "$GIT_EXEC_PATH"/git$X pretend/bin/ &&
+	GIT_EXEC_PATH= ./pretend/bin/git here >actual &&
+	echo HERE >expect &&
+	test_cmp expect actual
+'
+
 test_done
-- 
gitgitgadget

