[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:

I implemented this suggestion in https://github.com/llvm/llvm-project/pull/132250/commits/3ca23ce42044b84507efd96874bea30cec437ff0 -- but this led to repeating `BugTypes[ ... ]` nine times and I feel that it might be a bit too verbose.

I would slightly prefer switching back to using `CheckerPartIdx` as the type of these parameters (to make these already cumbersome calls _a bit_ less verbose), but I can also accept using `BugType` if you say that it's better.

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