[clang] [NFC][analyzer] Multipart checker refactor 2: NullabilityChecker (PR #132250)

[Donát Nagy via cfe-commits]

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@@ -491,7 +503,7 @@ void NullabilityChecker::reportBugIfInvariantHolds(
     N = C.addTransition(OriginalState, N);
   }
 
-  reportBug(Msg, Error, CK, N, Region, C.getBugReporter(), ValueExpr);
+  reportBug(Msg, Error, Idx, N, Region, C.getBugReporter(), ValueExpr);
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NagyDonat wrote:

Good idea, I'll implement it.

I didn't think about this question and just mechanically translated the `enum CheckKind` (essentially another integer type) to `CheckerPartIdx` -- but in this particular checker it will be only used to get `BugTypes[Idx]` so I can switch to passing a bug type ref.

https://github.com/llvm/llvm-project/pull/132250