t0013: add a basic sha1 collision detection test

We don't actually have a Git-object collision, so the best
we can do is to run one of the shattered PDFs through
test-sha1. This should trigger the collision check and die.

In a sense this isn't really checking anything that the
upstream sha1collisiondetection project doesn't cover
already. But it at least makes sure that our build correctly
uses the library.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/t/t0013-sha1dc.sh b/t/t0013-sha1dc.sh
new file mode 100755
index 0000000000..6d655cb161
--- /dev/null
+++ b/t/t0013-sha1dc.sh
@@ -0,0 +1,19 @@
+#!/bin/sh
+
+test_description='test sha1 collision detection'
+. ./test-lib.sh
+TEST_DATA="$TEST_DIRECTORY/t0013"
+
+if test -z "$DC_SHA1"
+then
+	skip_all='skipping sha1 collision tests, DC_SHA1 not set'
+	test_done
+fi
+
+test_expect_success 'test-sha1 detects shattered pdf' '
+	test_must_fail test-sha1 <"$TEST_DATA/shattered-1.pdf" 2>err &&
+	test_i18ngrep collision err &&
+	grep 38762cf7f55934b34d179ae6a4c80cadccbb7f0a err
+'
+
+test_done