598 findings to none, and the suite ran through `./run.sh run` after each step
rather than at the end -- 18 passed, 27s, every time.
The shape of this one was different from the other courses. PORR is four
implementations of the same linear algebra (sequential, threads, processes,
dask), so nearly every finding came in groups of four:
- 229 missing annotations. Rather than `object`, which mypy strict rejects on
every attribute access, each module declares what these actually are:
`Matrix = np.ndarray | list[list[float]]` and the vector equivalent. The
backends really are called with both -- comparing them is the point of the
course.
- 76 names: `A` -> matrix, `Ab` -> augmented, `Ax` -> product, `I` ->
identity, `dA` -> dask_matrix, and the two CamelCase functions. Renamed
through `tokenize`, not regex, so no string or comment was touched.
- 121 missing docstrings, one per method name since the names repeat across
all four backends.
- Seven functions over the argument limit, all taking the same seven or nine
loose values. They are two frozen dataclasses now, in a new
richardson_problem.py: `Problem(matrix, rhs, lambda_min, lambda_max)` and
`Settings(max_iterations, x0, tol)`. `RichardsonMethod.__init__` also took a
`size` argument it never read.
- threads_indep_old's iteration did "split into chunks, submit, wait" four
times by hand (C901 11, PLR0915 54). One `_run_chunked` helper.
- tests.py's two bare asserts became explicit raises, per the no-ignores rule.
`assert False` was also B011: `python -O` deletes it, so the non-convergence
branch would have silently passed under optimisation.
Real fixes rather than style: np.random -> Generator, `os.path.exists` ->
Path, an `except Exception` around dask narrowed to the errors it actually
raises, and two runnable modules that logged at INFO without ever calling
basicConfig -- caught by scripts/check_refactor_safety.py, which is now doing
the job it was written for.
Repo-wide: 1,781 findings -> 1,183, all of them in the five courses left.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0172dj34FDpao6wsix8ZuCzE
