libstdc++: Add filesystem::copy_symlink tests [PR122217]

libstdc++-v3/Changelog:

	PR libstdc++/122217
	* testsuite/27_io/filesystem/operations/copy_symlink/1.cc: New
	test.
	* testsuite/27_io/filesystem/operations/copy_symlink/2.cc: New
	test.
	* testsuite/27_io/filesystem/operations/copy_symlink/3.cc: New
	test.
	* testsuite/27_io/filesystem/operations/copy_symlink/4.cc: New
	test.

libstdc++-v3/testsuite/27_io/filesystem/operations/copy_symlink/1.cc

@@ -0,0 +1,63 @@
+// { dg-do run { target c++17 } }
+// { dg-require-filesystem-ts "" }
+
+#include <filesystem>
+#include <testsuite_hooks.h>
+#include <testsuite_fs.h>
+
+// Test successful copies
+
+namespace fs = std::filesystem;
+
+void
+test_successful_copy(const fs::path& p,
+		     bool (*is_some_file_type)(const fs::path&))
+{
+  const std::error_code bad_ec = make_error_code(std::errc::invalid_argument);
+  std::error_code ec;
+
+  auto to1 = read_symlink(p);
+
+  auto p2 = __gnu_test::nonexistent_path();
+  ec = bad_ec;
+  copy_symlink(p, p2, ec);
+  VERIFY( !ec );
+  VERIFY( exists(symlink_status(p2)) );
+  VERIFY( is_symlink(p2) );
+  VERIFY( is_some_file_type(p2) );
+  auto to2 = read_symlink(p2);
+  VERIFY( to1 == to2 );
+
+  // Copy again without ec
+  remove(p2);
+  copy_symlink(p, p2);
+  VERIFY( exists(symlink_status(p2)) );
+  VERIFY( is_symlink(p2) );
+  VERIFY( is_some_file_type(p2) );
+  to2 = read_symlink(p2);
+  VERIFY( to1 == to2 );
+
+  remove(p);
+  remove(p2);
+}
+
+void
+test01()
+{
+  __gnu_test::scoped_file f;
+  auto p = __gnu_test::nonexistent_path();
+  create_symlink(f.path, p);
+  test_successful_copy(p, fs::is_regular_file);
+
+  auto dir = __gnu_test::nonexistent_path();
+  create_directory(dir);
+  create_directory_symlink(dir, p);
+  test_successful_copy(p, fs::is_directory);
+  remove_all(dir);
+}
+
+int
+main()
+{
+  test01();
+}

libstdc++-v3/testsuite/27_io/filesystem/operations/copy_symlink/2.cc

@@ -0,0 +1,43 @@
+// { dg-do run { target c++17 } }
+// { dg-require-filesystem-ts "" }
+
+#include <filesystem>
+#include <testsuite_hooks.h>
+#include <testsuite_fs.h>
+
+// Test copying into an existing file
+
+void
+test01()
+{
+  std::error_code ec, ec2;
+  __gnu_test::scoped_file f, f2;
+
+  auto p = __gnu_test::nonexistent_path();
+  create_symlink(f.path, p);
+
+  copy_symlink(p, f2.path, ec);
+  VERIFY( ec );
+  VERIFY( !is_symlink(f2.path) );
+
+  try
+    {
+      copy_symlink(p, f2.path);
+    }
+  catch (const std::filesystem::filesystem_error& ex)
+    {
+      ec2 = ex.code();
+      VERIFY( ex.path1() == p );
+      VERIFY( ex.path2() == f2.path );
+    }
+  VERIFY( ec2 == ec );
+  VERIFY( !is_symlink(f2.path) );
+
+  remove(p);
+}
+
+int
+main()
+{
+  test01();
+}

libstdc++-v3/testsuite/27_io/filesystem/operations/copy_symlink/3.cc

@@ -0,0 +1,47 @@
+// { dg-do run { target c++17 } }
+// { dg-require-filesystem-ts "" }
+
+#include <filesystem>
+#include <testsuite_hooks.h>
+#include <testsuite_fs.h>
+
+// Test copying from a non-symlink
+
+namespace fs = std::filesystem;
+
+void
+test_copy_from_non_symlink(const fs::path& from)
+{
+  std::error_code ec, ec2;
+  auto p = __gnu_test::nonexistent_path();
+  copy_symlink(from, p, ec);
+  VERIFY( ec );
+  VERIFY( !is_symlink(p) );
+
+  try
+    {
+      copy_symlink(from, p);
+    }
+  catch (const fs::filesystem_error& ex)
+    {
+      ec2 = ex.code();
+      VERIFY( ex.path1() == from );
+      VERIFY( ex.path2() == p );
+    }
+  VERIFY( ec2 == ec );
+  VERIFY( !is_symlink(p) );
+}
+
+void
+test01()
+{
+  __gnu_test::scoped_file f;
+  test_copy_from_non_symlink(f.path);
+  test_copy_from_non_symlink(__gnu_test::nonexistent_path());
+}
+
+int
+main()
+{
+  test01();
+}

libstdc++-v3/testsuite/27_io/filesystem/operations/copy_symlink/4.cc

@@ -0,0 +1,44 @@
+// { dg-do run { target c++17 } }
+// { dg-require-filesystem-ts "" }
+
+#include <filesystem>
+#include <testsuite_hooks.h>
+#include <testsuite_fs.h>
+
+// Test copying into an empty path
+
+namespace fs = std::filesystem;
+
+void
+test01()
+{
+  std::error_code ec, ec2;
+  __gnu_test::scoped_file f, f2;
+
+  auto p = __gnu_test::nonexistent_path();
+  create_symlink(f.path, p);
+
+  fs::path empty;
+  copy_symlink(p, empty, ec);
+  VERIFY( ec );
+
+  try
+    {
+      copy_symlink(p, empty);
+    }
+  catch (const std::filesystem::filesystem_error& ex)
+    {
+      ec2 = ex.code();
+      VERIFY( ex.path1() == p );
+      VERIFY( ex.path2() == empty );
+    }
+  VERIFY( ec2 == ec );
+
+  remove(p);
+}
+
+int
+main()
+{
+  test01();
+}