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cefbc76490
Closes https://github.com/ppy/osu/issues/29738.
This "regressed" in https://github.com/ppy/osu/pull/29639, but if I
didn't know better, I'd go as far as saying that this looks like a .NET
bug, because the fact that PR broke it looks not sane.
The TL;DR on this is that before the pull in question, the offending
`.Contains()` check that this commit modifies was called on a
`List<BeatmapSetInfo>`. The pull changed the collection type to
`BeatmapSetInfo[]`. That said, the call is a LINQ call, so all good,
right?
Not really. First off, the default overload resolution order means that
the previous code would call `List<T>.Contains()`, and not
`Enumerable.Contains<T>()`. Then again, why would that matter? In both
cases `T` is still `BeatmapSetInfo`, right? Well... about that...
It is difficult to tell for sure what precisely is happening here,
because of what looks like runtime magic. The end *symptom* is that the
old code ended up calling `Array<BeatmapSetInfo>.IndexOf()`, and the new
code ends up calling... `Array<object>.IndexOf()`.
So while yes, `BeatmapSetInfo` implements `IEquatable` and
the expectation would be that `Equals<BeatmapSetInfo>()` should be
getting called, the type elision to `object` means that we're back to
reference equality semantics, because that's what
`EqualityComparer.Default<object>` is.
A five-minute github search across dotnet/runtime yields this:
|
||
|---|---|---|
| .. | ||
| Audio | ||
| Beatmaps | ||
| Collections | ||
| Configuration | ||
| Database | ||
| Extensions | ||
| Graphics | ||
| Input | ||
| IO | ||
| IPC | ||
| Localisation | ||
| Models | ||
| Online | ||
| Overlays | ||
| Performance | ||
| Properties | ||
| Replays | ||
| Rulesets | ||
| Scoring | ||
| Screens | ||
| Skinning | ||
| Storyboards | ||
| Tests | ||
| Updater | ||
| Users | ||
| Utils | ||
| .editorconfig | ||
| FodyWeavers.xml | ||
| osu!.res | ||
| osu.Game.csproj | ||
| OsuGame.cs | ||
| OsuGameBase_Importing.cs | ||
| OsuGameBase.cs | ||
| PerformFromMenuRunner.cs | ||