[Mlir-commits] [mlir] [mlir][ods] Enable basic string interpolation in constraint summary. (PR #153603)

[Rob Springer]

================
@@ -113,6 +127,56 @@ StringRef StaticVerifierFunctionEmitter::getRegionConstraintFn(
 // Constraint Emission
 //===----------------------------------------------------------------------===//
 
+/// Helper to generate a C++ string expression from a given message.
+/// Message can contain '{{...}}' placeholders that are substituted with
+/// C-expressions via tgfmt.
+std::string mlir::tblgen::buildErrorStreamingString(
+    StringRef message, const FmtContext &ctx, ErrorStreamType errorStreamType) {
+  std::string result;
+  raw_string_ostream os(result);
+
+  std::string msgStr = escapeString(message);
+  StringRef msg = msgStr;
+
+  // Split the message by '{{' and '}}' and build a streaming expression.
+  auto split = msg.split("{{");
+  if (split.second.empty()) {
+    os << split.first;
+    return msgStr;
+  }
+
+  os << split.first;
+  if (errorStreamType == ErrorStreamType::InsideOpError)
+    os << "\")";
+  else
+    os << '"';
+
+  msg = split.second;
+  while (!msg.empty()) {
+    split = msg.split("}}");
+    StringRef var = split.first;
+    StringRef rest = split.second;
+
+    os << " << " << tgfmt(var, &ctx);
+
+    if (rest.empty())
+      break;
+
+    split = rest.split("{{");
+    if (split.second.empty() &&
+        errorStreamType == ErrorStreamType::InsideOpError) {
+      // To enable having part of string post, this adds a parenthesis before
+      // the last string segment to match the exiting one.
----------------
RobSpringer wrote:

s/exiting/existing/

https://github.com/llvm/llvm-project/pull/153603