Merge 653aec68afdcadaae9913d7baf79f738fac538d2 into a0f06a70e3da7afa88da9527c43951bca1f7cef2

Fixes: #2066
PiperOrigin-RevId: 955981465
Change-Id: I6b34dc2e634d4b727a50fb3e21e5d8e25c39a13b

googletest/include/gtest/gtest-printers.h

@@ -945,13 +945,13 @@ template <typename T>
 class [[nodiscard]] UniversalPrinter<std::optional<T>> {
  public:
   static void Print(const std::optional<T>& value, ::std::ostream* os) {
-    *os << '(';
     if (!value) {
-      *os << "nullopt";
+      UniversalPrint(std::nullopt, os);
     } else {
+      *os << '(';
       UniversalPrint(*value, os);
+      *os << ')';
     }
-    *os << ')';
   }
 };
 
@@ -961,27 +961,38 @@ class [[nodiscard]] UniversalPrinter<std::nullopt_t> {
   static void Print(std::nullopt_t, ::std::ostream* os) { *os << "(nullopt)"; }
 };
 
+struct UniversalPrinterVisitor {
+  template <typename T>
+  void operator()(const T& arg) const {
+    *os << "'" << GetTypeName<T>() << "(index = " << index << ")' with value ";
+    UniversalPrint(arg, os);
+  }
+  ::std::ostream* os;
+  std::size_t index;
+};
+
 // Printer for std::variant
 template <typename... T>
 class [[nodiscard]] UniversalPrinter<std::variant<T...>> {
  public:
   static void Print(const std::variant<T...>& value, ::std::ostream* os) {
-    *os << '(';
-    std::visit(Visitor{os, value.index()}, value);
-    *os << ')';
-  }
-
- private:
-  struct Visitor {
-    template <typename U>
-    void operator()(const U& u) const {
-      *os << "'" << GetTypeName<U>() << "(index = " << index
-          << ")' with value ";
-      UniversalPrint(u, os);
+    if (value.valueless_by_exception()) {
+      *os << "(valueless)";
+    } else {
+      *os << '(';
+      std::visit(UniversalPrinterVisitor{os, value.index()}, value);
+      *os << ')';
     }
-    ::std::ostream* os;
-    std::size_t index;
-  };
+  }
+};
+
+// Printer for std::monostate
+template <>
+class [[nodiscard]] UniversalPrinter<std::monostate> {
+ public:
+  static void Print(std::monostate, ::std::ostream* os) {
+    *os << "(monostate)";
+  }
 };
 
 // UniversalPrintArray(begin, len, os) prints an array of 'len'

googletest/src/gtest-filepath.cc

@@ -227,12 +227,12 @@ FilePath FilePath::RemoveFileName() const {
 FilePath FilePath::MakeFileName(const FilePath& directory,
                                 const FilePath& base_name, int number,
                                 const char* extension) {
+  std::string base = base_name.IsEmpty() ? "file" : base_name.string();
   std::string file;
   if (number == 0) {
-    file = base_name.string() + "." + extension;
+    file = base + "." + extension;
   } else {
-    file =
-        base_name.string() + "_" + StreamableToString(number) + "." + extension;
+    file = base + "_" + StreamableToString(number) + "." + extension;
   }
   return ConcatPaths(directory, FilePath(file));
 }

googletest/test/googletest-filepath-test.cc

@@ -274,6 +274,18 @@ TEST(MakeFileNameTest, GenerateWhenNumberIsNotZeroAndDirIsEmpty) {
   EXPECT_EQ("bar_14.xml", actual.string());
 }
 
+TEST(MakeFileNameTest, GenerateWhenBaseNameEmpty) {
+  FilePath actual =
+      FilePath::MakeFileName(FilePath("foo"), FilePath(""), 0, "xml");
+  EXPECT_EQ("foo" GTEST_PATH_SEP_ "file.xml", actual.string());
+}
+
+TEST(MakeFileNameTest, GenerateWhenBaseNameEmptyNumberNonZero) {
+  FilePath actual =
+      FilePath::MakeFileName(FilePath("foo"), FilePath(""), 42, "xml");
+  EXPECT_EQ("foo" GTEST_PATH_SEP_ "file_42.xml", actual.string());
+}
+
 TEST(ConcatPathsTest, WorksWhenDirDoesNotEndWithPathSep) {
   FilePath actual = FilePath::ConcatPaths(FilePath("foo"), FilePath("bar.xml"));
   EXPECT_EQ("foo" GTEST_PATH_SEP_ "bar.xml", actual.string());

googletest/test/googletest-printers-test.cc

@@ -2030,6 +2030,26 @@ TEST(PrintOneofTest, Basic) {
       PrintToString(Type(NonPrintable{})));
 }
 
+TEST(PrintVariantTest, Monostate) {
+  EXPECT_EQ("(monostate)", PrintToString(std::monostate()));
+
+#if GTEST_HAS_EXCEPTIONS
+  struct ThrowOnMove {
+    ThrowOnMove() = default;
+    ThrowOnMove(ThrowOnMove&& other) { *this = std::move(other); }
+    ThrowOnMove& operator=(ThrowOnMove&&) {
+      (void)std::vector<bool>().at(0);
+      return *this;
+    }
+  };
+  std::variant<std::monostate, ThrowOnMove> v = std::monostate();
+  EXPECT_EQ("('std::monostate(index = 0)' with value (monostate))",
+            PrintToString(v));
+  EXPECT_THROW(v = ThrowOnMove(), std::out_of_range);
+  EXPECT_EQ("(valueless)", PrintToString(v));
+#endif
+}
+
 #if GTEST_INTERNAL_HAS_COMPARE_LIB
 TEST(PrintOrderingTest, Basic) {
   EXPECT_EQ("(less)", PrintToString(std::strong_ordering::less));