Pretty printer test fixes and improvements

Test that StdUniquePtrPrinter correctly prints std::unique_ptr objects
using the old layout, prior to the PR libstdc++/77990 changes.

The printer test for a valueless std::variant started to fail because
the PR libstdc++/87431 fix meant it no longer became valueless. Change
the test to use a type that is not trivially copyable, so that the
exception causes it to become valueless.

	* testsuite/libstdc++-prettyprinters/compat.cc: Test printer support
	for old std::unique_ptr layout.
	* testsuite/libstdc++-prettyprinters/cxx17.cc: Fix std::variant test
	to become valueless. Add filesystem::path tests.

From-SVN: r267743

libstdc++-v3/ChangeLog

 2019-01-08  Jonathan Wakely  <jwakely@redhat.com>
 
+	* testsuite/libstdc++-prettyprinters/compat.cc: Test printer support
+	for old std::unique_ptr layout.
+	* testsuite/libstdc++-prettyprinters/cxx17.cc: Fix std::variant test
+	to become valueless. Add filesystem::path tests.
+
 	PR libstdc++/87855
 	* include/std/optional (_Optional_payload_base): New class template
 	for common code hoisted from _Optional_payload specializations. Use

libstdc++-v3/testsuite/libstdc++-prettyprinters/compat.cc

@@ -23,6 +23,22 @@
 
 namespace std
 {
+  template<typename T, typename U>
+    struct tuple
+    {
+      T _M_head_impl;
+    };
+
+  template<typename T> struct default_delete { };
+
+  template<typename T, typename D = default_delete<T>>
+    struct unique_ptr
+    {
+      unique_ptr(T* p) { _M_t._M_head_impl = p; }
+
+      tuple<T*, D> _M_t;
+    };
+
   // Old representation of std::optional, before GCC 9
   template<typename T>
     struct _Optional_payload
@@ -58,6 +74,12 @@ namespace std
 int
 main()
 {
+  struct datum { };
+  std::unique_ptr<datum> uptr (new datum);
+// { dg-final { regexp-test uptr {std::unique_ptr.datum. = {get\(\) = 0x.*}} } }
+  std::unique_ptr<datum> &ruptr = uptr;
+// { dg-final { regexp-test ruptr {std::unique_ptr.datum. = {get\(\) = 0x.*}} } }
+
   using std::optional;
 
   optional<int> o;

libstdc++-v3/testsuite/libstdc++-prettyprinters/cxx17.cc

@@ -22,6 +22,7 @@
 // Type printers only recognize the old std::string for now.
 #define _GLIBCXX_USE_CXX11_ABI 0
 
+#include <filesystem>
 #include <any>
 #include <optional>
 #include <variant>
@@ -41,6 +42,11 @@ using std::unordered_set;
 using std::shared_ptr;
 using std::weak_ptr;
 
+struct X {
+  X(int) { }
+  X(const X&) { } // not trivially-copyable
+};
+
 int
 main()
 {
@@ -84,11 +90,11 @@ main()
 // { dg-final { note-test v0 {std::variant<float, int, std::string_view> [index 0] = {0}} } }
   variant<float, int, string_view> v1{ 0.5f };
 // { dg-final { note-test v1 {std::variant<float, int, std::string_view> [index 0] = {0.5}} } }
-  variant<float, int, string_view> v2;
+  variant<float, X, string_view> v2;
   try {
     v2.emplace<1>(S());
   } catch (int) { }
-// { dg-final { note-test v2 {std::variant<float, int, std::string_view> [no contained value]} } }
+// { dg-final { note-test v2 {std::variant<float, X, std::string_view> [no contained value]} } }
   variant<float, int, string_view> v3{ 3 };
 // { dg-final { note-test v3 {std::variant<float, int, std::string_view> [index 1] = {3}} } }
   variant<float, int, string_view> v4{ str };
@@ -118,6 +124,13 @@ main()
 // { dg-final { regexp-test q {std::shared_ptr.int \[2\]. \(use count 2, weak count 1\) = {get\(\) = 0x.*}} } }
 // { dg-final { regexp-test wq {std::weak_ptr.int \[2\]. \(use count 2, weak count 1\) = {get\(\) = 0x.*}} } }
 
+  std::filesystem::path p0;
+// { dg-final { note-test p0 {filesystem::path ""} } }
+  std::filesystem::path p1("filename");
+// { dg-final { note-test p1 {filesystem::path "filename"} } }
+  std::filesystem::path p2("/dir/.");
+// { dg-final { note-test p2 {filesystem::path "/dir/file" = {[root-directory] = "/", [1] = "dir", [2] = "."}} } }
+
   std::cout << "\n";
   return 0;			// Mark SPOT
 }