env--helper: new undocumented builtin wrapping git_env_*()

We have many GIT_TEST_* variables that accept a <boolean> because
they're implemented in C, and then some that take <non-empty?> because
they're implemented at least partially in shellscript.

Add a helper that wraps git_env_bool() and git_env_ulong() as the
first step in fixing this. This isn't being added as a test-tool mode
because some of these are used outside the test suite.

Part of what this tool does can be done via a trick with "git config"
added in 83d842dc8c ("tests: turn on network daemon tests by default",
2014-02-10) for test_tristate(), i.e.:

    git -c magic.variable="$1" config --bool magic.variable 2>/dev/null

But as subsequent changes will show being able to pass along the
default value makes all the difference, and we'll be able to replace
test_tristate() itself with that.

The --type=bool option will be used by subsequent patches, but not
--type=ulong. I figured it was easy enough to add it & test for it so
I left it in so we'd have wrappers for both git_env_*() functions, and
to have a template to make it obvious how we'd add --type=int etc. if
it's needed in the future.

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

1 files changed, 83 insertions, 0 deletions

diff --git a/t/t0017-env-helper.sh b/t/t0017-env-helper.sh
new file mode 100755
index 0000000..709bbbd
--- /dev/null
+++ b/t/t0017-env-helper.sh
@@ -0,0 +1,83 @@
+#!/bin/sh
+
+test_description='test env--helper'
+
+. ./test-lib.sh
+
+
+test_expect_success 'env--helper usage' '
+	test_must_fail git env--helper &&
+	test_must_fail git env--helper --type=bool &&
+	test_must_fail git env--helper --type=ulong &&
+	test_must_fail git env--helper --type=bool &&
+	test_must_fail git env--helper --type=bool --default &&
+	test_must_fail git env--helper --type=bool --default= &&
+	test_must_fail git env--helper --defaultxyz
+'
+
+test_expect_success 'env--helper bad default values' '
+	test_must_fail git env--helper --type=bool --default=1xyz MISSING &&
+	test_must_fail git env--helper --type=ulong --default=1xyz MISSING
+'
+
+test_expect_success 'env--helper --type=bool' '
+	# Test various --default bool values
+	echo true >expected &&
+	git env--helper --type=bool --default=1 MISSING >actual &&
+	test_cmp expected actual &&
+	git env--helper --type=bool --default=yes MISSING >actual &&
+	test_cmp expected actual &&
+	git env--helper --type=bool --default=true MISSING >actual &&
+	test_cmp expected actual &&
+	echo false >expected &&
+	test_must_fail git env--helper --type=bool --default=0 MISSING >actual &&
+	test_cmp expected actual &&
+	test_must_fail git env--helper --type=bool --default=no MISSING >actual &&
+	test_cmp expected actual &&
+	test_must_fail git env--helper --type=bool --default=false MISSING >actual &&
+	test_cmp expected actual &&
+
+	# No output with --exit-code
+	git env--helper --type=bool --default=true --exit-code MISSING >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err &&
+	test_must_fail git env--helper --type=bool --default=false --exit-code MISSING >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err &&
+
+	# Existing variable
+	EXISTS=true git env--helper --type=bool --default=false --exit-code EXISTS >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err &&
+	test_must_fail \
+		env EXISTS=false \
+		git env--helper --type=bool --default=true --exit-code EXISTS >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err
+'
+
+test_expect_success 'env--helper --type=ulong' '
+	echo 1234567890 >expected &&
+	git env--helper --type=ulong --default=1234567890 MISSING >actual.out 2>actual.err &&
+	test_cmp expected actual.out &&
+	test_must_be_empty actual.err &&
+
+	echo 0 >expected &&
+	test_must_fail git env--helper --type=ulong --default=0 MISSING >actual &&
+	test_cmp expected actual &&
+
+	git env--helper --type=ulong --default=1234567890 --exit-code MISSING >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err &&
+
+	EXISTS=1234567890 git env--helper --type=ulong --default=0 EXISTS --exit-code >actual.out 2>actual.err &&
+	test_must_be_empty actual.out &&
+	test_must_be_empty actual.err &&
+
+	echo 1234567890 >expected &&
+	EXISTS=1234567890 git env--helper --type=ulong --default=0 EXISTS >actual.out 2>actual.err &&
+	test_cmp expected actual.out &&
+	test_must_be_empty actual.err
+'
+
+test_done