Expanded path functions tests

The new tests cover:
- A file with empty extension.
- A file with only extension (a "hidden" file, unix style).
- A file directly at the windows top level directory.
- A file directly at the unix root directory.
- A file directly at the res:// base directory.

tests/test_string.h

@@ -1142,14 +1142,14 @@ TEST_CASE("[String] dedent") {
 }
 
 TEST_CASE("[String] Path functions") {
-	static const char *path[4] = { "C:\\Godot\\project\\test.tscn", "/Godot/project/test.xscn", "../Godot/project/test.scn", "Godot\\test.doc" };
-	static const char *base_dir[4] = { "C:\\Godot\\project", "/Godot/project", "../Godot/project", "Godot" };
-	static const char *base_name[4] = { "C:\\Godot\\project\\test", "/Godot/project/test", "../Godot/project/test", "Godot\\test" };
-	static const char *ext[4] = { "tscn", "xscn", "scn", "doc" };
-	static const char *file[4] = { "test.tscn", "test.xscn", "test.scn", "test.doc" };
-	static const bool abs[4] = { true, true, false, false };
-
-	for (int i = 0; i < 4; i++) {
+	static const char *path[7] = { "C:\\Godot\\project\\test.tscn", "/Godot/project/test.xscn", "../Godot/project/test.scn", "Godot\\test.doc", "C:\\test.", "res://test", "/.test" };
+	static const char *base_dir[7] = { "C:\\Godot\\project", "/Godot/project", "../Godot/project", "Godot", "C:\\", "res://", "/" };
+	static const char *base_name[7] = { "C:\\Godot\\project\\test", "/Godot/project/test", "../Godot/project/test", "Godot\\test", "C:\\test", "res://test", "/" };
+	static const char *ext[7] = { "tscn", "xscn", "scn", "doc", "", "", "test" };
+	static const char *file[7] = { "test.tscn", "test.xscn", "test.scn", "test.doc", "test.", "test", ".test" };
+	static const bool abs[7] = { true, true, false, false, true, true, true };
+
+	for (int i = 0; i < 7; i++) {
 		CHECK(String(path[i]).get_base_dir() == base_dir[i]);
 		CHECK(String(path[i]).get_basename() == base_name[i]);
 		CHECK(String(path[i]).get_extension() == ext[i]);