The tests/json/bson_corpus directory contains both tests from the upstream specifications repository as well as custom tests. In some cases, tests in this directory are modified copies of the upstream tests.

Consider: some multi-byte UTF encoding tests were manually modified in mongodb/libbson@980546a (before libbson was merged into libmongoc). There is no record of these manual modifications.

In another case, mongodb/libbson@980546a introduced a double2.json file, which is not found in the upstream repository. That is in contrast to a decimal128-mongoc.json file introduced in mongodb/libbson@a7ad680, which at least has a differentiated file name.

All modified tests should be organized into their own directory. The bson_corpus directory should then contain exact copies of any upstream tests, with skips added to test-bson-corpus.c as needed. Rather than modified upstream tests, we should skip the originals and create modified copies in a separate directroy.