[Chromoting] Add InputInjector and InputInjectorWrapper for easy unittesting

remoting/android/javatests/src/org/chromium/chromoting/MockInputInjector.java

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chromoting;
+
+import android.graphics.PointF;
+
+import junit.framework.Assert;
+
+import org.chromium.chromoting.jni.TouchEventData;
+
+import java.util.Arrays;
+import java.util.LinkedList;
+
+/**
+ * A mock implementation of {@link InputInjector} for testing purpose.
+ */
+public final class MockInputInjector extends Assert implements InputInjector {
+    /** The base class to store an event, which represents an user activity. */
+    public abstract static class Event<T> {
+        public void assertEventEquals(T other) {
+            if (other == this) {
+                return;
+            }
+            if (other == null) {
+                fail();
+            }
+
+            assertContentMatch(other);
+        }
+
+        protected abstract void assertContentMatch(T other);
+    }
+
+    /** A mouse event. */
+    public static final class MouseEvent extends Event<MouseEvent> {
+        private final int mX;
+        private final int mY;
+        private final int mButton;
+        private final boolean mDown;
+
+        public MouseEvent(int x, int y, int button, boolean down) {
+            mX = x;
+            mY = y;
+            mButton = button;
+            mDown = down;
+        }
+
+        @Override
+        protected void assertContentMatch(MouseEvent other) {
+            assertEquals(mX, other.mX);
+            assertEquals(mY, other.mY);
+            assertEquals(mButton, other.mButton);
+            assertEquals(mDown, other.mDown);
+        }
+    }
+
+    /** A mouse wheel event. */
+    public static final class WheelEvent extends Event<WheelEvent> {
+        private final int mDeltaX;
+        private final int mDeltaY;
+
+        public WheelEvent(int deltaX, int deltaY) {
+            mDeltaX = deltaX;
+            mDeltaY = deltaY;
+        }
+
+        @Override
+        protected void assertContentMatch(WheelEvent other) {
+            assertEquals(mDeltaX, other.mDeltaX);
+            assertEquals(mDeltaY, other.mDeltaY);
+        }
+    }
+
+    /** A keyboard event. */
+    public static final class KeyEvent extends Event<KeyEvent> {
+        private final int mScanCode;
+        private final int mKeyCode;
+        private final boolean mKeyDown;
+
+        public KeyEvent(int scanCode, int keyCode, boolean keyDown) {
+            mScanCode = scanCode;
+            mKeyCode = keyCode;
+            mKeyDown = keyDown;
+        }
+
+        @Override
+        protected void assertContentMatch(KeyEvent other) {
+            assertEquals(mScanCode, other.mScanCode);
+            assertEquals(mKeyCode, other.mKeyCode);
+            assertEquals(mKeyDown, other.mKeyDown);
+        }
+    }
+
+    /** A text event. */
+    public static final class TextEvent extends Event<TextEvent> {
+        public final String mText;
+
+        public TextEvent(String text) {
+            mText = text;
+        }
+
+        @Override
+        protected void assertContentMatch(TextEvent other) {
+            if (mText == null && other.mText == null) {
+                return;
+            }
+            if (mText == null || other.mText == null) {
+                fail();
+            }
+            assertEquals(mText, other.mText);
+        }
+    }
+
+    /** A touch event. */
+    public static final class TouchEvent extends Event<TouchEvent> {
+        /**
+         * A random number to represent an invalid touch id for {@link assertContentMatch}.
+         * Consumers can use this number to ignore the comparison of
+         * {@link TouchEventData#getTouchPointId()} when comparing.
+         */
+        public static final int INVALID_ID = -883;
+
+        /**
+         * A random number to represent an invalid position for {@link #assertContentMatch}.
+         * Consumers can use this number to ignore certain float fields in an {@link TouchEventData}
+         * when comparing.
+         */
+        public static final float INVALID_POSITION = -763.273f;
+
+        /**
+         * A number to represent an invalid angle in radians for {@link #assertContentMatch}.
+         * Consumers can use this number to ignore the comparison of
+         * {@link TouchEventData#getTouchPointAngle} when comparing.
+         */
+        public static final float INVALID_RADIANS = 6.289f * (float) Math.PI;
+
+        // TouchEventData stores degrees instead of radians
+        private static final float INVALID_DEGREES = (float) Math.toDegrees(INVALID_RADIANS);
+        private final TouchEventData.EventType mEventType;
+        private final TouchEventData[] mData;
+
+        public TouchEvent(TouchEventData.EventType eventType, TouchEventData[] data) {
+            mEventType = eventType;
+            mData = (data == null ? null : Arrays.copyOf(data, data.length));
+        }
+
+        private static boolean idMatch(int left, int right) {
+            return left == right || left == INVALID_ID || right == INVALID_ID;
+        }
+
+        private static boolean positionMatch(float left, float right) {
+            return left == right || left == INVALID_POSITION || right == INVALID_POSITION;
+        }
+
+        private static boolean degreeMatch(float left, float right) {
+            return left == right || left == INVALID_DEGREES || right == INVALID_DEGREES;
+        }
+
+        private static void assertContentMatch(TouchEventData left, TouchEventData right) {
+            assertTrue(idMatch(left.getTouchPointId(), right.getTouchPointId()));
+            assertTrue(positionMatch(left.getTouchPointX(), right.getTouchPointX()));
+            assertTrue(positionMatch(left.getTouchPointY(), right.getTouchPointY()));
+            assertTrue(positionMatch(left.getTouchPointRadiusX(), right.getTouchPointRadiusX()));
+            assertTrue(positionMatch(left.getTouchPointRadiusY(), right.getTouchPointRadiusY()));
+            assertTrue(degreeMatch(left.getTouchPointAngle(), right.getTouchPointAngle()));
+            assertTrue(positionMatch(left.getTouchPointPressure(), right.getTouchPointPressure()));
+        }
+
+        private static void assertDataEquals(TouchEventData left, TouchEventData right) {
+            if (left == null && right == null) {
+                return;
+            }
+            if (left == null || right == null) {
+                fail();
+            }
+            assertContentMatch(left, right);
+        }
+
+        private int dataSize() {
+            return mData == null ? 0 : mData.length;
+        }
+
+        @Override
+        protected void assertContentMatch(TouchEvent other) {
+            assertEquals(mEventType, other.mEventType);
+            // An empty TouchEventData array indicates mData field is not interested.

[Lambros, 2016/06/22 01:43:14]

Spell it out more clearly. Perhaps:
An event with an empty mData array will
match an event with a non-empty mData array.
This is useful for tests which expect a TouchEvent, but
don't care about the content of mData.

[Hzj_jie, 2016/06/22 23:18:54]

Done.

+            if (dataSize() != 0 && other.dataSize() != 0) {
+                assertEquals(dataSize(), other.dataSize());
+                for (int i = 0; i < dataSize(); i++) {
+                    assertDataEquals(mData[i], other.mData[i]);
+                }
+            }
+        }
+    }
+
+    private final LinkedList<MouseEvent> mMouseEvents;
+    private final LinkedList<WheelEvent> mWheelEvents;
+    private final LinkedList<KeyEvent> mKeyEvents;
+    private final LinkedList<TextEvent> mTextEvents;
+    private final LinkedList<TouchEvent> mTouchEvents;
+
+    public MockInputInjector() {
+        mMouseEvents = new LinkedList<>();
+        mWheelEvents = new LinkedList<>();
+        mKeyEvents = new LinkedList<>();
+        mTextEvents = new LinkedList<>();
+        mTouchEvents = new LinkedList<>();
+    }
+
+    /**
+     * Compares the first |right|.length events with the ones in |left|, asserts they are equal, and
+     * consumes these events from both |left| and |right|.

[Lambros, 2016/06/22 01:43:15]

This no longer consumes from |right|.

[Hzj_jie, 2016/06/22 23:18:54]

Done.

+     */
+    private static <E extends Event<E>> void assertContains(
+            LinkedList<E> left, E[] right) {
+        if (left == null && right == null) {
+            return;
+        }
+        if (left == null || right == null) {
+            fail();
+        }
+        assertTrue(left.size() >= right.length);

[Lambros, 2016/06/22 01:43:15]

JUnit has no assertGreaterThan() method :(
Instead, use assertTrue(String, boolean) to log a message that
[left] was smaller than [right]
(reporting the sizes in place of [left] and [right]).

[Hzj_jie, 2016/06/22 23:18:55]

Done.

+        for (int i = 0; i < right.length; i++) {
+            E leftEvent = left.removeFirst();
+            if (leftEvent == null) {
+                assertNull(right[i]);
+            } else {
+                leftEvent.assertEventEquals(right[i]);
+            }
+        }
+    }
+
+    public void clear() {
+        mMouseEvents.clear();
+        mWheelEvents.clear();
+        mKeyEvents.clear();
+        mTextEvents.clear();
+        mTouchEvents.clear();
+    }
+
+    /**
+     * Compares the first |other|.length events with {@link #mMouseEvents} in this instance,
+     * asserts they are equal, and consumes these events in both this instance and |other|.
+     */
+    public void assertContainsMouseEvents(MouseEvent[] other) {
+        assertContains(mMouseEvents, other);
+    }
+
+    /**
+     * Compares the first |other|.length events with {@link #mTouchEvents} in this instance,
+     * asserts they are equal, and consumes these events in both this instance and |other|.

[Lambros, 2016/06/22 01:43:14]

Doesn't consume |other|.

[Hzj_jie, 2016/06/22 23:18:55]

Done.

+     */
+    public void assertContainsTouchEvents(TouchEvent[] other) {
+        assertContains(mTouchEvents, other);
+    }
+
+    /** Asserts current instance is empty. */
+    public void assertEmpty() {
+        assertTrue(mMouseEvents.isEmpty());
+        assertTrue(mWheelEvents.isEmpty());
+        assertTrue(mKeyEvents.isEmpty());
+        assertTrue(mTextEvents.isEmpty());
+        assertTrue(mTouchEvents.isEmpty());
+    }
+
+    /**
+     * Checks whether the first two events in {@link #mTouchEvents} are representing a down and
+     * an up action at specified position |x|, |y|, and consumes these events.
+     */
+    public void assertTapInjected(float x, float y) {
+        assertTouchEventInjected(TouchEventData.EventType.TOUCH_EVENT_START, x, y);
+        assertTouchEventInjected(TouchEventData.EventType.TOUCH_EVENT_END, x, y);
+    }
+
+    /**
+     * Checks whether the first event in {@link #mTouchEvents} is representing an event with type
+     * |eventType| and at specified position |x|, |y|, and consumes this event.
+     */
+    public void assertTouchEventInjected(TouchEventData.EventType eventType, float x, float y) {
+        assertContainsTouchEvents(new TouchEvent[] {
+                new TouchEventBuilder()
+                        .withEventType(eventType)
+                        .withX(x)
+                        .withY(y)
+                        .append()
+                        .build(),
+        });
+    }
+
+    /**
+     * Checks whether the first event in {@link #mTouchEvents} is representing an event with type
+     * |eventType|, and consumes this event.
+     */
+    public void assertTouchEventInjected(TouchEventData.EventType eventType) {
+        assertContainsTouchEvents(new TouchEvent[] {
+                new TouchEventBuilder().withEventType(eventType).build(),
+        });
+    }
+
+    /**
+     * Checks whether the first two events in {@link #mMouseEvents} are representing a down and an
+     * up action with |button| at specified position |x|, |y|, and consumes these events.
+     */
+    public void assertClickInjected(int button, int x, int y) {
+        assertContainsMouseEvents(new MouseEvent[] {
+                new MouseEvent(x, y, button, true), new MouseEvent(x, y, button, false),
+        });
+    }
+
+    public void assertTouchMoveEventInjected(
+            PointF[] initPositions, int stepX, int stepY, int moveCount) {
+        LinkedList<TouchEvent> events = new LinkedList<>();
+        assertTrue(initPositions != null && initPositions.length > 0);
+        for (int i = 0; i < initPositions.length; i++) {
+            assertNotNull(initPositions[i]);
+            events.add(new TouchEventBuilder()
+                               .withEventType(TouchEventData.EventType.TOUCH_EVENT_START)
+                               .withX(initPositions[i].x)
+                               .withY(initPositions[i].y)
+                               .append()
+                               .build());
+        }
+
+        // These tests send a single event for each finger that is moved.  E.G. If we are injecting

[Lambros, 2016/06/22 01:43:14]

s/E.G. If/E.g. if/

[Hzj_jie, 2016/06/22 23:18:55]

Done.

+        // a pan event with two fingers, then every two TouchEvents represents one 'frame' of the
+        // motion sequence.  Here we determine which iteration this event represents so we can use
+        // that to accurately compare the locations with the expected values.
+        for (int i = 0; i < moveCount; i++) {
+            for (int j = 0; j < initPositions.length; j++) {
+                TouchEventBuilder builder = new TouchEventBuilder();
+                builder.withEventType(TouchEventData.EventType.TOUCH_EVENT_MOVE);
+                for (int k = 0; k < initPositions.length; k++) {
+                    // We inject one finger at a time which means that finger will have the correct
+                    // value but other fingers may still be stepSize behind it.
+                    int currentStep = i - 1;
+                    if (j >= k) {
+                        currentStep++;
+                    }
+                    if (currentStep < 0) {
+                        currentStep = 0;
+                    }
+                    builder.withX(initPositions[k].x + currentStep * stepX)
+                            .withY(initPositions[k].y + currentStep * stepY)
+                            .append();
+                }
+                events.add(builder.build());
+            }
+        }
+
+        assertContainsTouchEvents(events.toArray(new TouchEvent[0]));
+    }
+
+    /**
+     * Checks whether the first two events in {@link #mMouseEvents} are representing a down and an
+     * up action with right button at specified position |x|, |y|, and consumes these events.
+     */
+    public void assertRightClickInjected(int x, int y) {
+        assertClickInjected(TouchInputHandler.BUTTON_RIGHT, x, y);
+    }
+
+    // ---------------- Implementations of InputInjector ----------------------
+    @Override
+    public void sendMouseEvent(int x, int y, int whichButton, boolean buttonDown) {
+        mMouseEvents.add(new MouseEvent(x, y, whichButton, buttonDown));
+    }
+
+    @Override
+    public void sendMouseWheelEvent(int deltaX, int deltaY) {
+        mWheelEvents.add(new WheelEvent(deltaX, deltaY));
+    }
+
+    @Override
+    public boolean sendKeyEvent(int scanCode, int keyCode, boolean keyDown) {
+        mKeyEvents.add(new KeyEvent(scanCode, keyCode, keyDown));
+
+        // Note: This implementation is not consistent with jni.Client, which may return false when
+        // scanCode and keyCode cannot be mapped to a usb key code.
+        return true;
+    }
+
+    @Override
+    public void sendTextEvent(String text) {
+        mTextEvents.add(new TextEvent(text));
+    }
+
+    @org.chromium.base.annotations.SuppressFBWarnings("FE_FLOATING_POINT_EQUALITY")

[Lambros, 2016/06/22 01:43:14]

import org.chromium.base.annotations.SuppressFBWarnings
and just use SuppressFBWarnings here.

[Hzj_jie, 2016/06/22 23:18:55]

I have not seen any comments about using import or using full package qualified
name in the coding style. Do we always prefer to use import?

[Lambros, 2016/06/23 01:40:09]

Do you see any other examples in Chromium? A code-search for
"@org.chromium" finds nothing. I think we prefer import.

[Hzj_jie, 2016/06/23 18:03:24]

Good point. No, I did not find one.

+    @Override
+    public void sendTouchEvent(TouchEventData.EventType eventType, TouchEventData[] data) {
+        assertFalse(data == null || data.length == 0);

[Lambros, 2016/06/22 01:43:14]

This would be much more readable as:

assertNotNull(data);
assertTrue(data.length != 0);

[Hzj_jie, 2016/06/22 23:18:55]

Done.

+        for (int i = 0; i < data.length; i++) {
+            assertFalse(data[i].getTouchPointId() == TouchEvent.INVALID_ID);

[Lambros, 2016/06/22 01:43:15]

I think I prefer assertTrue(foo != INVALID) over assertFalse(foo == INVALID),
because positive checks are more readable than negative checks.
But feel free to disagree.

[Hzj_jie, 2016/06/22 23:18:55]

Done. :)

+            assertFalse(data[i].getTouchPointX() == TouchEvent.INVALID_POSITION);
+            assertFalse(data[i].getTouchPointY() == TouchEvent.INVALID_POSITION);
+            assertFalse(data[i].getTouchPointRadiusX() == TouchEvent.INVALID_POSITION);
+            assertFalse(data[i].getTouchPointRadiusY() == TouchEvent.INVALID_POSITION);
+            assertFalse(data[i].getTouchPointAngle() == TouchEvent.INVALID_DEGREES);
+            assertFalse(data[i].getTouchPointPressure() == TouchEvent.INVALID_POSITION);
+        }
+        mTouchEvents.add(new TouchEvent(eventType, data));
+    }
+}