mlir/unittests/IR/Diagnostic.cpp

   1 //===- Diagnostic.cpp - Dialect unit tests -------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "mlir/IR/Diagnostics.h"
  10 #include "mlir/Support/TypeID.h"
  11 #include "gtest/gtest.h"
  12
  13 using namespace mlir;
  14 using namespace mlir::detail;
  15
  16 namespace {
  17
  18 TEST(DiagnosticLifetime, TestCopiesConstCharStar) {
  19   const auto *expectedMessage = "Error 1, don't mutate this";
  20
  21   // Copy expected message into a mutable container, and call the constructor.
  22   std::string myStr(expectedMessage);
  23
  24   mlir::MLIRContext context;
  25   Diagnostic diagnostic(mlir::UnknownLoc::get(&context),
  26                         DiagnosticSeverity::Note);
  27   diagnostic << myStr.c_str();
  28
  29   // Mutate underlying pointer, but ensure diagnostic still has orig. message
  30   myStr[0] = '^';
  31
  32   std::string resultMessage;
  33   llvm::raw_string_ostream stringStream(resultMessage);
  34   diagnostic.print(stringStream);
  35   ASSERT_STREQ(expectedMessage, resultMessage.c_str());
  36 }
  37
  38 TEST(DiagnosticLifetime, TestLazyCopyStringLiteral) {
  39   char charArr[21] = "Error 1, mutate this";
  40   mlir::MLIRContext context;
  41   Diagnostic diagnostic(mlir::UnknownLoc::get(&context),
  42                         DiagnosticSeverity::Note);
  43
  44   // Diagnostic contains optimization which assumes string literals are
  45   // represented by `const char[]` type. This is imperfect as we can sometimes
  46   // trick the type system as seen below.
  47   //
  48   // Still we use this to check the diagnostic is lazily storing the pointer.
  49   auto addToDiagnosticAsConst = [&diagnostic](const char(&charArr)[21]) {
  50     diagnostic << charArr;
  51   };
  52   addToDiagnosticAsConst(charArr);
  53
  54   // Mutate the underlying pointer and ensure the string does change
  55   charArr[0] = '^';
  56
  57   std::string resultMessage;
  58   llvm::raw_string_ostream stringStream(resultMessage);
  59   diagnostic.print(stringStream);
  60   ASSERT_STREQ("^rror 1, mutate this", resultMessage.c_str());
  61 }
  62
  63 } // namespace