Add testcases for `RunForMillis()` simulator function

Signed-off-by: Michael Richters <gedankenexperimenter@gmail.com>

tests/simulator/timing/sketch.ino

@@ -0,0 +1,48 @@
+/* -*- mode: c++ -*-
+ * Copyright (C) 2020  Keyboard.io, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "Kaleidoscope.h"
+
+// *INDENT-OFF*
+
+KEYMAPS(
+  [0] = KEYMAP_STACKED
+  (
+    XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX
+
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+          ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX   ,XXX   ,XXX   ,XXX
+   ,XXX
+  )
+) // KEYMAPS(
+
+// *INDENT-ON*
+
+void setup() {
+  Kaleidoscope.setup();
+}
+
+void loop() {
+  Kaleidoscope.loop();
+}

tests/simulator/timing/test/testcase.cpp

@@ -0,0 +1,73 @@
+/* -*- mode: c++ -*-
+ * Copyright (C) 2020  Keyboard.io, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "testing/setup-googletest.h"
+
+SETUP_GOOGLETEST();
+
+namespace kaleidoscope {
+namespace testing {
+namespace {
+
+constexpr uint32_t t_0{0};
+constexpr uint32_t t_1{1};
+constexpr uint32_t t_100{100};
+constexpr uint32_t t_500{500};
+constexpr uint32_t t_500_000{500000};
+
+using ::testing::IsEmpty;
+
+class SimulatorTiming : public VirtualDeviceTest {
+ public:
+  void assertTimeElapses(uint32_t interval) {
+    // Record time at start
+    uint32_t start = Kaleidoscope.millisAtCycleStart();
+
+    // Run cycles until the given amount of time has elapsed
+    sim_.RunForMillis(interval);
+
+    // Record time at end
+    uint32_t end = Kaleidoscope.millisAtCycleStart();
+
+    ASSERT_EQ((end - start), interval);
+  }
+};
+
+TEST_F(SimulatorTiming, SimulatorStart) {
+  // Time doesn't advance in the simulator until after the first cycle runs
+  ASSERT_EQ(Kaleidoscope.millisAtCycleStart(), t_0);
+  RunCycle();
+  ASSERT_EQ(Kaleidoscope.millisAtCycleStart(), t_1);
+}
+
+TEST_F(SimulatorTiming, TimeElapses) {
+  assertTimeElapses(t_1);
+  assertTimeElapses(t_100);
+  assertTimeElapses(t_500);
+}
+
+TEST_F(SimulatorTiming, ZeroTimeElapses) {
+  assertTimeElapses(t_0);
+}
+
+TEST_F(SimulatorTiming, LongTimeElapses) {
+  // Bigger number than uint16_t can hold
+  assertTimeElapses(t_500_000);
+}
+
+}  // namespace
+}  // namespace testing
+}  // namespace kaleidoscope