commit 4e9ed5892c00482f2fed9ef2862cab203afec21d
author Mike Klein <mtklein@google.com> Thu Dec 12 12:20:07 2019 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Thu Dec 12 20:43:38 2019 +0000
tree 4596a6cf2e099a84d89b9442b9d2c39efd1da378
parent 04c7f4ea275fbec0f100f17870509360b674bc97

better parse mismatch dumps

Change-Id: I51f29d509853bcdc079647e9984842e5efec080a
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/259737
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>

tests.c

diff --git a/tests.c b/tests.c
index 092d1ad..9a47629 100644
--- a/tests.c
+++ b/tests.c
@@ -751,10 +751,19 @@
             expect(load_file(ref_filename, &ref_buf, &ref_len));
 
             if (dump_len != ref_len || memcmp(dump_buf, ref_buf, dump_len) != 0) {
+                const char* cur = dump_buf;
+                const char* ref =  ref_buf;
+                while (*cur == *ref) { cur++; ref++; }
+                size_t off = (size_t)(cur - (const char*)dump_buf);
                 // Write out the new data on a mismatch
                 fprintf(stderr, "Parse mismatch for %s:\n", filename);
                 fwrite(dump_buf, 1, dump_len, stderr);
                 fprintf(stderr, "\n");
+
+                fprintf(stderr, "Mismatch begins at offset %zu, expected '%c', got,\n", off, *ref);
+                fwrite(cur, 1, dump_len - off, stderr);
+                fprintf(stderr, "\n");
+
                 expect(false);
             }
             free(ref_buf);