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Print unique_ptr/shared_ptr recursively. Given that they are smart pointers, it is unlikely that the inner object is invalid. PiperOrigin-RevId: 351586888
google · Jan 14, 2021 · 6b2e749 · 6b2e749
1 parent 50ce520
commit 6b2e749
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Showing 2 changed files with 92 additions and 2 deletions.
diff --git a/googletest/include/gtest/gtest-printers.h b/googletest/include/gtest/gtest-printers.h
@@ -101,13 +101,15 @@
 #define GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
 
 #include <functional>
+#include <memory>
 #include <ostream>  // NOLINT
 #include <sstream>
 #include <string>
 #include <tuple>
 #include <type_traits>
 #include <utility>
 #include <vector>
+
 #include "gtest/internal/gtest-internal.h"
 #include "gtest/internal/gtest-port.h"
 
@@ -573,6 +575,43 @@ void PrintTo(std::reference_wrapper<T> ref, ::std::ostream* os) {
   UniversalPrinter<T&>::Print(ref.get(), os);
 }
 
+inline const void* VoidifyPointer(const void* p) { return p; }
+inline const void* VoidifyPointer(volatile const void* p) {
+  return const_cast<const void*>(p);
+}
+
+template <typename T, typename Ptr>
+void PrintSmartPointer(const Ptr& ptr, std::ostream* os, char) {
+  if (ptr == nullptr) {
+    *os << "(nullptr)";
+  } else {
+    // We can't print the value. Just print the pointer..
+    *os << "(" << (VoidifyPointer)(ptr.get()) << ")";
+  }
+}
+template <typename T, typename Ptr,
+          typename = typename std::enable_if<!std::is_void<T>::value &&
+                                             !std::is_array<T>::value>::type>
+void PrintSmartPointer(const Ptr& ptr, std::ostream* os, int) {
+  if (ptr == nullptr) {
+    *os << "(nullptr)";
+  } else {
+    *os << "(ptr = " << (VoidifyPointer)(ptr.get()) << ", value = ";
+    UniversalPrinter<T>::Print(*ptr, os);
+    *os << ")";
+  }
+}
+
+template <typename T, typename D>
+void PrintTo(const std::unique_ptr<T, D>& ptr, std::ostream* os) {
+  (PrintSmartPointer<T>)(ptr, os, 0);
+}
+
+template <typename T>
+void PrintTo(const std::shared_ptr<T>& ptr, std::ostream* os) {
+  (PrintSmartPointer<T>)(ptr, os, 0);
+}
+
 // Helper function for printing a tuple.  T must be instantiated with
 // a tuple type.
 template <typename T>

diff --git a/googletest/test/googletest-printers-test.cc b/googletest/test/googletest-printers-test.cc
@@ -32,15 +32,16 @@
 //
 // This file tests the universal value printer.
 
-#include <ctype.h>
-#include <string.h>
 #include <algorithm>
+#include <cctype>
 #include <cstdint>
+#include <cstring>
 #include <deque>
 #include <forward_list>
 #include <limits>
 #include <list>
 #include <map>
+#include <memory>
 #include <set>
 #include <sstream>
 #include <string>
@@ -1702,6 +1703,56 @@ TEST(UniversalPrintTest, IncompleteType) {
             PrintToString(reinterpret_cast<Incomplete&>(some_object)));
 }
 
+TEST(UniversalPrintTest, SmartPointers) {
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<int>()));
+  std::unique_ptr<int> p(new int(17));
+  EXPECT_EQ("(ptr = " + PrintPointer(p.get()) + ", value = 17)",
+            PrintToString(p));
+  std::unique_ptr<int[]> p2(new int[2]);
+  EXPECT_EQ("(" + PrintPointer(p2.get()) + ")", PrintToString(p2));
+
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<int>()));
+  std::shared_ptr<int> p3(new int(1979));
+  EXPECT_EQ("(ptr = " + PrintPointer(p3.get()) + ", value = 1979)",
+            PrintToString(p3));
+#if __cpp_lib_shared_ptr_arrays >= 201611L
+  std::shared_ptr<int[]> p4(new int[2]);
+  EXPECT_EQ("(" + PrintPointer(p4.get()) + ")", PrintToString(p4));
+#endif
+
+  // modifiers
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<const int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<volatile int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<volatile const int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<int[]>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<const int[]>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<volatile int[]>()));
+  EXPECT_EQ("(nullptr)",
+            PrintToString(std::unique_ptr<volatile const int[]>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<const int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<volatile int>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<volatile const int>()));
+#if __cpp_lib_shared_ptr_arrays >= 201611L
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<int[]>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<const int[]>()));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<volatile int[]>()));
+  EXPECT_EQ("(nullptr)",
+            PrintToString(std::shared_ptr<volatile const int[]>()));
+#endif
+
+  // void
+  EXPECT_EQ("(nullptr)", PrintToString(std::unique_ptr<void, void (*)(void*)>(
+                             nullptr, nullptr)));
+  EXPECT_EQ("(" + PrintPointer(p.get()) + ")",
+            PrintToString(
+                std::unique_ptr<void, void (*)(void*)>(p.get(), [](void*) {})));
+  EXPECT_EQ("(nullptr)", PrintToString(std::shared_ptr<void>()));
+  EXPECT_EQ("(" + PrintPointer(p.get()) + ")",
+            PrintToString(std::shared_ptr<void>(p.get(), [](void*) {})));
+}
+
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsEmptyTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(::std::make_tuple());
   EXPECT_EQ(0u, result.size());