## Changes
- Remove bundle.Parallel & bundle.ReadOnlyBundle.
- Add bundle.ApplyParallel, as a helper to migrate from bundle.Parallel.
- Keep ReadOnlyMutator as a separate type but it's now a subtype of
Mutator so it works on regular *Bundle. Having it as a separate type
prevents non-readonly mutators being passed to ApplyParallel
- validate.Validate becomes a function (was Mutator).
## Why
This a follow up to #2390 where we removed most of the tools to
construct chains of mutators. Same motivation applies here.
When it comes to read-only bundles, it's a leaky abstraction -- since
it's a shallow copy, it does not actually guarantee or enforce readonly
access to bundle. A better approach would be to run parallel operations
on independent narrowly-focused deep-copied structs, with just enough
information to carry out the task (this is not implemented here, but the
eventual goal). Now that we can just write regular code in phases and
not limited to mutator interface, we can switch to that approach.
## Tests
Existing tests.
---------
Co-authored-by: shreyas-goenka <88374338+shreyas-goenka@users.noreply.github.com>
## Changes
- Print warnings and errors by default.
- Fix ErrAlreadyPrinted not to be logged at Error level.
- Format log messages as "Warn: message" instead of "WARN" to make it
more readable and in-line with the rest of the output.
- Only print attributes (pid, mutator, etc) and time when the overall
level is debug (so --debug output has not changed much).
## Tests
- Existing acceptance tests show how warning messages appear in various
test case.
- Added new test for `--debug` output.
- Add sort_lines.py helper to avoid dependency on 'sort' which is
locale-sensitive.
Denis Bilenko