Add testcase for the active keys cache

This testcase checks to make sure that the active keys cache gets cleared by
`handleKeyswitchEvent()` when a plugin returns `EVENT_CONSUMED`.

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

tests/features/events/active-keys/release-cleared/common.h

@@ -0,0 +1,27 @@
+// -*- mode: c++ -*-
+
+/* Kaleidoscope - Firmware for computer input devices
+ * 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/>.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+namespace kaleidoscope {
+namespace testing {
+
+}  // namespace testing
+}  // namespace kaleidoscope

tests/features/events/active-keys/release-cleared/release-cleared.ino

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+/* -*- 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>
+
+#include "./common.h"
+
+#undef min
+#undef max
+#include <iostream>
+
+// *INDENT-OFF*
+KEYMAPS(
+    [0] = KEYMAP_STACKED
+    (
+        Key_A, ___, ___, ___, ___, ___, ___,
+        ShiftToLayer(1), ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___,
+
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___
+    ),
+    [1] = KEYMAP_STACKED
+    (
+        Key_X, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___,
+
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___
+    ),
+)
+// *INDENT-ON*
+
+namespace kaleidoscope {
+namespace plugin {
+
+class ConvertXtoY : public kaleidoscope::Plugin {
+ public:
+  EventHandlerResult onKeyswitchEvent(Key &key, KeyAddr key_addr, uint8_t key_state) {
+    if (keyToggledOn(key_state)) {
+      if (key == Key_X)
+        key = Key_Y;
+    }
+    // It should be impossible to get a `Key_X` at this point, because the
+    // previous block changes any `Key_X` to `Key_Y`, which results in the
+    // active keys cache storing that value. On subsequent cycles (while the key
+    // is still pressed), the `key` value should be `Key_Y`.
+    if (keyIsPressed(key_state) && key == Key_X) {
+      std::cerr << "t=" << Runtime.millisAtCycleStart() << ": "
+                << "Error: we shouldn't see a key with value `X`" << std::endl;
+    }
+    // When `Key_Y` toggles off, return `EVENT_CONSUMED`. Despite this, the
+    // active keys cache entry should be cleared. If it's not, then a subsequent
+    // press of the same key without the layer shift in effect will still result
+    // in `Key_Y` instead of `Key_A`.
+    if (keyToggledOff(key_state) && (key == Key_Y)) {
+      return EventHandlerResult::EVENT_CONSUMED;
+    }
+    return EventHandlerResult::OK;
+  }
+};
+
+} // namespace plugin
+} // namespace kaleidoscope
+
+kaleidoscope::plugin::ConvertXtoY ConvertXtoY;
+
+KALEIDOSCOPE_INIT_PLUGINS(ConvertXtoY);
+
+void setup() {
+  Kaleidoscope.setup();
+}
+
+void loop() {
+  Kaleidoscope.loop();
+}

tests/features/events/active-keys/release-cleared/sketch.json

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+{
+  "cpu": {
+    "fqbn": "keyboardio:virtual:model01",
+    "port": ""
+  }
+}

tests/features/events/active-keys/release-cleared/test.ktest

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+VERSION 1
+
+KEYSWITCH A 0 0
+KEYSWITCH LAYER_SHIFT 1 0
+
+# ==============================================================================
+# Active Keys Cache
+NAME Active keys cache cleared
+
+RUN 10 ms
+
+PRESS A
+RUN 1 cycle
+EXPECT keyboard-report Key_A # Report should contain only `A`
+
+RUN 5 ms
+
+RELEASE A
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# Press and hold `ShiftToLayer(1)`, changing the `A` key to `X`
+PRESS LAYER_SHIFT
+RUN 5 ms
+
+# Press `X`, which gets converted to `Y` by the `ConvertXtoY` plugin defined in
+# the sketch. The plugin simply changes the value of the key, which causes it to
+# get set to `Key_Y` in the active keys cache.
+PRESS A
+RUN 1 cycle
+EXPECT keyboard-report Key_Y # Report should contain only `Y`
+
+RUN 5 ms
+
+# Release the `X` key (on Layer 1), which has become a `Y` key in the active
+# keys cache. This should clear its entry in that cache.
+RELEASE A
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# Release `ShiftToLayer(1)`. This should restore the `A` key to its base layer
+# value on subsequent presses, unless the Macros key gets "stuck" in the active
+# keys array because it returns `EVENT_CONSUMED`.
+RELEASE LAYER_SHIFT
+RUN 5 ms
+
+PRESS A
+RUN 1 cycle
+EXPECT keyboard-report Key_A # Report should contain only `A`
+
+RUN 5 ms
+
+RELEASE A
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty