Googletest export

Add support for printing incomplete types in the universal printer.

PiperOrigin-RevId: 350154637

Author: Abseil Team

googletest/include/gtest/gtest-printers.h

@@ -261,16 +261,23 @@ struct ConvertibleToStringViewPrinter {
 GTEST_API_ void PrintBytesInObjectTo(const unsigned char* obj_bytes,
                                      size_t count,
                                      ::std::ostream* os);
-struct FallbackPrinter {
-  template <typename T>
+struct RawBytesPrinter {
+  // SFINAE on `sizeof` to make sure we have a complete type.
+  template <typename T, size_t = sizeof(T)>
   static void PrintValue(const T& value, ::std::ostream* os) {
     PrintBytesInObjectTo(
-        static_cast<const unsigned char*>(
-            reinterpret_cast<const void*>(std::addressof(value))),
+        reinterpret_cast<const unsigned char*>(std::addressof(value)),
         sizeof(value), os);
   }
 };
 
+struct FallbackPrinter {
+  template <typename T>
+  static void PrintValue(const T&, ::std::ostream* os) {
+    *os << "(incomplete type)";
+  }
+};
+
 // Try every printer in order and return the first one that works.
 template <typename T, typename E, typename Printer, typename... Printers>
 struct FindFirstPrinter : FindFirstPrinter<T, E, Printers...> {};
@@ -297,7 +304,7 @@ void PrintWithFallback(const T& value, ::std::ostream* os) {
       T, void, ContainerPrinter, FunctionPointerPrinter, PointerPrinter,
       internal_stream_operator_without_lexical_name_lookup::StreamPrinter,
       ProtobufPrinter, ConvertibleToIntegerPrinter,
-      ConvertibleToStringViewPrinter, FallbackPrinter>::type;
+      ConvertibleToStringViewPrinter, RawBytesPrinter, FallbackPrinter>::type;
   Printer::PrintValue(value, os);
 }
 

googletest/test/googletest-printers-test.cc

@@ -1695,6 +1695,13 @@ TEST(UniversalPrintTest, WorksForCharArray) {
   EXPECT_EQ("\"\\\"Line\\0 1\\\"\\nLine 2\"", ss2.str());
 }
 
+TEST(UniversalPrintTest, IncompleteType) {
+  struct Incomplete;
+  char some_object = 0;
+  EXPECT_EQ("(incomplete type)",
+            PrintToString(reinterpret_cast<Incomplete&>(some_object)));
+}
+
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsEmptyTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(::std::make_tuple());
   EXPECT_EQ(0u, result.size());