To make it easier for future tests to use the arbitrary specialisations
we've defined for some nix types, centralize them all in a single
arbitrary.hh header file.
Change-Id: I767f27949cfe7ec55c79901f7d7aa538d2f98c6b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2182
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>
Add missing break statements to the big switch block in
BuildResult::FromProto, and cover the whole thing with a rapidcheck
round-trip test.
Change-Id: I7a07ca398cc5f02ca4fd8e6256fd563c6f3aea9d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2178
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>