Implement combined axis logic and tests.

internal/mappingrules/test_mocks.go

@@ -7,9 +7,32 @@ import (
 
 type InputDeviceMock struct {
 	mock.Mock
+	calls []*mock.Call
+}
+
+func NewInputDeviceMock() *InputDeviceMock {
+	m := new(InputDeviceMock)
+	m.calls = make([]*mock.Call, 0, 10)
+	return m
 }
 
 func (m *InputDeviceMock) AbsInfos() (map[evdev.EvCode]evdev.AbsInfo, error) {
 	args := m.Called()
 	return args.Get(0).(map[evdev.EvCode]evdev.AbsInfo), args.Error(1)
 }
+
+// TODO: this would make a great library class functioning as a slight improvement on testify's
+// mocks for instances where we want to redefine behavior more often...
+// (alternately, this is possibly an anti-pattern in Go, in which case find a cleaner way to do this and remove)
+func (m *InputDeviceMock) Stub(method string) *mock.Call {
+	call := m.On(method)
+	m.calls = append(m.calls, call)
+	return call
+}
+
+func (m *InputDeviceMock) Reset() {
+	for _, call := range m.calls {
+		call.Unset()
+	}
+	m.calls = make([]*mock.Call, 0, 10)
+}