chore: add GUT test framework

addons/gut/test/unit/test_double_tools.gd

@@ -0,0 +1,82 @@
+extends GutInternalTester
+
+
+class FakeBase:
+	var foo = 'foo'
+
+	func set_foo(val):
+		foo = val
+
+	func get_foo():
+		return foo
+
+
+class FakeDouble:
+	extends FakeBase
+
+
+
+
+class TestTheBasics:
+	extends GutInternalTester
+
+	var DoubleTools = load("res://addons/gut/double_tools.gd")
+	var Stubber = load("res://addons/gut/stubber.gd")
+	var StubParams = load("res://addons/gut/stub_params.gd")
+
+	var call_this_was_called = false
+	func call_this(value):
+		call_this_was_called = value
+
+	func before_each():
+		call_this_was_called = false
+
+
+	func test_can_make_one():
+		assert_not_null(DoubleTools.new())
+
+	func test_get_method_to_call_returns_null_when_not_stubbed():
+		var fd = FakeDouble.new()
+		var stbr = Stubber.new()
+
+		var dt = DoubleTools.new()
+		dt.stubber_ref = weakref(stbr)
+		dt.double_ref = weakref(fd)
+
+		assert_null(dt.handle_other_stubs('set_foo', [1]))
+
+
+	func test_handle_other_stubs_calls_method():
+		var fd = FakeDouble.new()
+
+		var sp = StubParams.new(fd.set_foo)
+		sp.to_call(call_this)
+
+		var stbr = Stubber.new()
+		stbr.add_stub(sp)
+
+		var dt = DoubleTools.new()
+		dt.stubber_ref = weakref(stbr)
+		dt.double_ref = weakref(fd)
+
+		dt.handle_other_stubs('set_foo', [1])
+		assert_eq(call_this_was_called, 1)
+		stbr.clear()
+
+
+	func test_handle_other_stubs_returns_value():
+		var fd = FakeDouble.new()
+
+		var sp = StubParams.new(fd.get_foo)
+		sp.to_call(func(): return 'asdf')
+
+		var stbr = Stubber.new()
+		stbr.add_stub(sp)
+
+		var dt = DoubleTools.new()
+		dt.stubber_ref = weakref(stbr)
+		dt.double_ref = weakref(fd)
+
+		var result = dt.handle_other_stubs('get_foo', [])
+		assert_eq(result, 'asdf')
+		stbr.clear()