[clang] [clang-tools-extra] [clang][tidy] Ensure rewriter has the correct CWD (PR #67839)

[Jan Svoboda via cfe-commits]

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@@ -227,6 +227,14 @@ class ErrorReporter {
           llvm::errs() << "Can't apply replacements for file " << File << "\n";
         }
       }
+
+      auto BuildDir = Context.getCurrentBuildDirectory();
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jansvoboda11 wrote:

You're right, the `clang-tidy/infrastructure/clang-tidy-run-with-database.cpp` test kept passing just by chance. I added extra test case to prove that we need to keep closer track for each file what was the CWD when we processed it.

https://github.com/llvm/llvm-project/pull/67839