Re: [PATCH 2/5] t5303: test some corrupt deltas

From: Jeff King <peff@peff.net>
Date: Aug 30, 2018, 18:42 UTC
Message-ID: <20180830184201.GB14273@sigill.intra.peff.net>
In-Reply-To: <xmqq8t4n69gy.fsf@gitster-ct.c.googlers.com>

On Thu, Aug 30, 2018 at 10:38:21AM -0700, Junio C Hamano wrote:

Show 12 quoted lines

> Jeff King <peff@peff.net> writes:
> 
> > +test_expect_success \
> > +    'apply delta with too many copied bytes' \
> > +    'printf "\5\1\221\0\2" > too_big_copy &&
> > +     echo base >base &&
> > +     test_must_fail test-tool delta -p base too_big_copy /dev/null'
> 
> Would "echo base >base" give us 5-byte long base even on Windows?
> Or the test does not care if it is either "base\n" or "base\r\n"?
> 
> Just double-checking.

Good question. On the first one, I don't know. On the second one, yes, it does matter. We'd feed "6" to patch_delta(), and it would complain about the mismatch before actually hitting the code we're trying to exercise. The test would still pass (the error result is the same either way), but would quietly not test what we wanted.

Maybe something like this to be on the safe side?

(note that we can leave the \5 in the result size of the "truncated copy parameters" test; it really just needs to be larger than 1).

---

diff --git a/t/t5303-pack-corruption-resilience.sh b/t/t5303-pack-corruption-resilience.sh
index 912e659acf..e80934a18e 100755
--- a/t/t5303-pack-corruption-resilience.sh
+++ b/t/t5303-pack-corruption-resilience.sh
@@ -327,15 +327,15 @@ test_expect_success \
     'printf "\0\1\2XX" > too_big_literal &&
      test_must_fail test-tool delta -p /dev/null too_big_literal /dev/null'
 
-# \5 - five bytes in base
+# \4 - four bytes in base
 # \1 - one byte in result
 # \221 - copy, one byte offset, one byte size
 #   \0 - copy from offset 0
 #   \2 - copy two bytes (one too many)
 test_expect_success \
     'apply delta with too many copied bytes' \
-    'printf "\5\1\221\0\2" > too_big_copy &&
-     echo base >base &&
+    'printf "\4\1\221\0\2" > too_big_copy &&
+     printf base >base &&
      test_must_fail test-tool delta -p base too_big_copy /dev/null'
 
 # \0 - empty base
@@ -356,7 +356,7 @@ test_expect_success \
     'printf "\0\1\221\0\1" > truncated_base &&
      test_must_fail test-tool delta -p /dev/null truncated_base /dev/null'
 
-# \5 - five bytes in base
+# \4 - four bytes in base
 # \5 - five bytes in result
 # \1 - one literal byte (X)
 # \221 - copy, one byte offset, one byte size
@@ -366,8 +366,8 @@ test_expect_success \
 # delta size check.
 test_expect_failure \
     'apply delta with truncated copy parameters' \
-    'printf "\5\5\1X\221" > truncated_copy_delta &&
-     echo base >base &&
+    'printf "\4\5\1X\221" > truncated_copy_delta &&
+     printf base >base &&
      test_must_fail test-tool delta -p base truncated_copy_delta /dev/null'
 
 test_done