SrcUriFilenameDotPrefix: new check for SRC_URI filenames with dot prefix

[arthurzam]

Resolves: https://github.com/pkgcore/pkgcheck/issues/585

[codecov[bot]]

Codecov Report

Patch coverage: 80.00% and project coverage change: -0.01 :warning:

Comparison is base (afc779b) 79.88% compared to head (e48c3ef) 79.88%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #592 +/- ## ========================================== - Coverage 79.88% 79.88% -0.01% ========================================== Files 57 57 Lines 8536 8545 +9 Branches 1939 1941 +2 ========================================== + Hits 6819 6826 +7 - Misses 1617 1618 +1 - Partials 100 101 +1 ``` | [Impacted Files](https://app.codecov.io/gh/pkgcore/pkgcheck/pull/592?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pkgcore) | Coverage Δ | | |---|---|---| | [src/pkgcheck/checks/metadata.py](https://app.codecov.io/gh/pkgcore/pkgcheck/pull/592?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pkgcore#diff-c3JjL3BrZ2NoZWNrL2NoZWNrcy9tZXRhZGF0YS5weQ==) | `89.29% <80.00%> (-0.11%)` | :arrow_down: |

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[mgorny]

I wonder if we shouldn't simply put it in bad_filenames.

[arthurzam]

I wonder if we shouldn't simply put it in bad_filenames.

@mgorny I'm unsure about it. While simpler, the BadFilename is quite ambiguous, and I'm unsure anybody will understand what it means in practice. Here we have a more specialized case, where we warn the develop - "you might have done big mistake, reverify".

I think it will be better to have more info than less here.