[clang-tools-extra] [clang-query] Load queries and matchers from file during REPL cycle (PR #90603)

[Aaron Ballman via cfe-commits]

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@@ -281,5 +282,26 @@ const QueryKind SetQueryKind<bool>::value;
 const QueryKind SetQueryKind<OutputKind>::value;
 #endif
 
+bool FileQuery::run(llvm::raw_ostream &OS, QuerySession &QS) const {
+  auto Buffer = llvm::MemoryBuffer::getFile(StringRef{File}.trim());
+  if (!Buffer) {
+    if (Prefix.has_value())
+      llvm::errs() << *Prefix << ": ";
+    llvm::errs() << "cannot open " << File << ": "
+                 << Buffer.getError().message() << "\n";
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AaronBallman wrote:

Rather than printing directly to `errs()`, I think you should construct a `TextDiagnostic` object and use that to emit the diagnostic.

https://github.com/llvm/llvm-project/pull/90603