# RC-009: Code review of MIL-001 (project foundation: constants, package, tests)

## Metadata
| Key | Value |
| --- | --- |
| ID | RC-009 |
| CrossReference | [MIL-001], [QC-PY-001] |

## Version History
| Date | Status | Author | Reviewer | Change | Commit |
| --- | --- | --- | --- | --- | --- |
| 2026-10-13 | Proposed | Jens Tirsvad Nielsen | AI as stand-in for S01 | Initial version | pending |

---

## Artifact Under Review

- Instance reviewed: the source and tests that [MIL-001] delivers (project foundation: constants, package, tests)
- Checklist used: [QC-PY-001]
- Scope: full review of the files changed on the branch of the milestone
- Language and domain: n/a
- Language reviewer: none
- Mode: autonomous, not independent (the reviewer is `AI as stand-in for S01`; the assistant also wrote the code; the review of the files was done by the `python-developer` agent of the session)

## Checklist Results

| # | Criterion | Status | Evidence/Notes |
| --- | --- | --- | --- |
| 1 | Packages, modules, functions, variables, classes and constants follow PEP 8 casing (`snake_case`, `PascalCase`, `UPPER_SNAKE`) | Pass | `PACKAGE_DIR`, `DATA_FILE_NAME` and the other constants are `UPPER_SNAKE`; test functions and the fixture are `snake_case`; the package is `weather`. |
| 2 | Names state purpose in the domain's language; no unexplained abbreviations, no single-letter names outside tiny scopes | Pass | Names state purpose (`FAHRENHEIT_NUMERATOR`, `TEMP_COLUMN_INDEX`, `DATA_FILE`); `temp` is the column name of the lecture's file. |
| 3 | Code is produced by the project's formatter and passes its linter with no unexplained suppressions | Pass | `python -m ruff check src tests` and `python -m ruff format --check src tests` exit 0 with the selection E, F, W, I, N, UP, B, SIM; no `noqa` or ignore. |
| 4 | Every function and method signature is type-annotated, including `-> None` | Pass | Every test function and the fixture are annotated `-> None`; the constants are `Final[...]` annotated. |
| 5 | No bare `except:`, no swallowed exceptions; specific exceptions are raised and the cause is kept (`raise ... from`) | N-A | The changed files contain no exception handling. |
| 6 | No mutable default arguments and no shadowed builtins | Pass | No function has a mutable default and no builtin is shadowed. |
| 7 | Files, locks and connections are managed with context managers | N-A | The changed files open no file. |
| 8 | Public modules, classes and functions have docstrings that say what, not how | Pass | Every constant has a Doxygen `##` comment; the package, `constants.py` and the test and fixture modules have docstrings; `doxygen Doxyfile` ends with 0 warnings. |
| 9 | Logging uses `logging`, not `print`; no secrets or personal data in log output | N-A | The changed files neither log nor print. |
| 10 | Classes and operations trace to the Design Class Diagram they implement; deviations are recorded | Pass | No class exists in these files; the project has no Design Class Diagram (a learning project of this size, recorded in the open issues of [PP-001]). |
| 11 | Tests exist for new behaviour, are named for the behaviour, and do not depend on order or the network | Pass | `tests/test_constants.py` has tests named for the value they fix; none depends on order or the network; the autouse fixture runs each test in a temporary folder. |
| 12 | Type checker runs in strict mode without errors; `Any` is justified in a comment | Pass | `python -m mypy` runs with `strict = true` and reports no issues; no `Any`. |
| 13 | Dependencies are declared and pinned in the project's dependency file, none unused | Pass | `dependencies = []`; the `pandas` extra and the `dev` extra declare `pandas`, `pandas-stubs`, pytest, ruff and mypy with lower bounds; pandas is used by the later milestones. |
| 14 | Each piece of knowledge (a business rule, constant, format, validation or query) is defined in one place; code is merged only where it expresses the same knowledge, not where it merely looks alike | Pass | Every value of the lectures is defined once in `constants.py`; `DATA_FILE` is derived from `PACKAGE_DIR` and `DATA_FILE_NAME`; the Fahrenheit factors are separate constants. |
| 15 | Imports point inward: business-rule modules import no framework, database, UI or delivery-mechanism code, and there are no import cycles | Pass | `constants.py` imports only `pathlib.Path` and `typing.Final`; no import cycle. |
| 16 | SOLID holds: a class or module has one reason to change; new behaviour is added by extension, not by editing a type test in several places; subclasses honour the contract of their base; protocols are narrow; high-level code depends on protocols or abstract types and receives its implementations | Pass | A module of constants has one reason to change; there is no class to extend. |

## Overall Verdict

Go — all Mandatory criteria pass or are not applicable. Assessed on 2026-10-13 by the assistant that wrote the code, as stand-in for S01 in autonomous mode. Mode: autonomous, not independent. The pull request is the second look.

## Action Items

| Action | Owner | Due |
| --- | --- | --- |
| Challenge this `Go` in the run summary or on the pull request if the stand-in decision is not wanted | S01 | 2026-10-23 |

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[MIL-001]: ../../milestones/mil-001-project-foundation.md
[QC-PY-001]: ../../../framework/qc/code/qc-programming-python.md
[PP-001]: ../../project-plan.md