Add structured error information for errors from `lifetime_analysis`.
PiperOrigin-RevId: 521986503
diff --git a/lifetime_annotations/lifetime_error.h b/lifetime_annotations/lifetime_error.h
new file mode 100644
index 0000000..fde8dd0
--- /dev/null
+++ b/lifetime_annotations/lifetime_error.h
@@ -0,0 +1,46 @@
+// Part of the Crubit project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef THIRD_PARTY_CRUBIT_LIFETIME_ANNOTATIONS_LIFETIME_ERROR_H_
+#define THIRD_PARTY_CRUBIT_LIFETIME_ANNOTATIONS_LIFETIME_ERROR_H_
+
+#include "llvm/Support/Error.h"
+
+namespace clang {
+namespace tidy {
+namespace lifetimes {
+
+// Error information for errors that originate in the `lifetime_analysis`
+// package.
+class LifetimeError : public llvm::ErrorInfo<LifetimeError> {
+ public:
+ enum class Type {
+ ElisionNotEnabled,
+ CannotElideOutputLifetimes,
+ Other,
+ };
+
+ LifetimeError(Type type, std::string message)
+ : type_(type), message_(std::move(message)) {}
+
+ Type type() const { return type_; }
+
+ void log(llvm::raw_ostream& OS) const override { OS << message_; }
+
+ std::error_code convertToErrorCode() const override {
+ return llvm::inconvertibleErrorCode();
+ }
+
+ static char ID;
+
+ private:
+ Type type_;
+ std::string message_;
+};
+
+} // namespace lifetimes
+} // namespace tidy
+} // namespace clang
+
+#endif // THIRD_PARTY_CRUBIT_LIFETIME_ANNOTATIONS_LIFETIME_ERROR_H_
