[clang-tools-extra] [Clang-Tidy] Handle nested-name-specifier in "llvm-prefer-isa-or-dyn-cast-in-conditionals" (PR #155982)

[Yanzuo Liu via cfe-commits]

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@@ -76,6 +136,16 @@ bool foo(Y *y, Z *z) {
   // CHECK-MESSAGES: :[[@LINE-2]]:7: warning: isa_and_nonnull<> is preferred
   // CHECK-FIXES: if (isa_and_nonnull<Y>(z->bar()))
 
+  if (z->bar() && cast_or_null<Y>(z->bar()))
+    return true;
+  // CHECK-MESSAGES: :[[@LINE-2]]:7: warning: isa_and_nonnull<> is preferred
+  // CHECK-FIXES: if (isa_and_nonnull<Y>(z->bar()))
+
+  if (z->bar() && cast_if_present<Y>(z->bar()))
+    return true;
+  // CHECK-MESSAGES: :[[@LINE-2]]:7: warning: isa_and_nonnull<> is preferred
+  // CHECK-FIXES: if (isa_and_nonnull<Y>(z->bar()))
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zwuis wrote:

I want to revert this part and add support in a separate PR that

- Keep `_present` and `_or_null` as written.
- Replace `x && isa<Y>(x)` with what configuration files choose (`isa_and_nonnull` or `isa_and_present`).

WDYT?

https://github.com/llvm/llvm-project/pull/155982