This patch makes protoio use the new protobuf API for
marshalling/unmarshalling text protobufs, as well as extends the tests
to cover marshalling failures.
The protobuf text output is not stable/deterministic and some spaces are
added randomly, so some integration tests have to be adjusted to account
for it.
This patch adds some test cases for I/O errors, in particular when
reading, writing and listing from files that don't exist or that we
shouldn't have permissions to access.
In the protoio tests, we were using unkeyed fields in some composite
literals. This can cause confusion and makes the code more brittle wrt.
future changes. go vet also complains about this.
This patch fixes the issue by adding the field names to the struct
initializations.
This patch extends various packages and integration tests, increasing
test coverage. They're small enough that it's not worth splitting them
up, as it would add a lot of noise to the history.
We have many places in our tests where we create temporary directories,
which we later remove (most of the time). We have at least 3 helpers to
do this, and various places where it's done ad-hoc (and the cleanup is
not always present).
To try to reduce the clutter, and make the tests more uniform and
readable, this patch introduces two helpers in a new "testutil" package:
one for creating and one for removing temporary directories.
These new functions are safer, better tested, and make the tests more
consistent. All the tests are updated to use them.
