fix: memory leak (#22)

Author: ttzztztz

src/EventTarget.js

@@ -1,100 +1,100 @@
-const _events = new Map()
-
-class Touch {
-    constructor(touch) {
-        // CanvasTouch{identifier, x, y}
-        // Touch{identifier, pageX, pageY, clientX, clientY, force}
-        this.identifier = touch.identifier
-
-        this.force = touch.force === undefined ? 1 : touch.force
-        this.pageX = touch.pageX || touch.x
-        this.pageY = touch.pageY || touch.y
-        this.clientX = touch.clientX || touch.x
-        this.clientY = touch.clientY || touch.y
-
-        this.screenX = this.pageX
-        this.screenY = this.pageY
-    }
-}
-
-export default class EventTarget {
-    constructor() {
-        _events.set(this, {})
-    }
-
-    addEventListener(type, listener, options = {}) {
-        let events = _events.get(this)
-
-        if (!events) {
-            events = {}
-            _events.set(this, events)
-        }
-        if (!events[type]) {
-            events[type] = []
-        }
-        events[type].push(listener)
-
-        if (options.capture) {
-            // console.warn('EventTarget.addEventListener: options.capture is not implemented.')
-        }
-        if (options.once) {
-            // console.warn('EventTarget.addEventListener: options.once is not implemented.')
-        }
-        if (options.passive) {
-            // console.warn('EventTarget.addEventListener: options.passive is not implemented.')
-        }
-    }
-
-    removeEventListener(type, listener) {
-        const events = _events.get(this)
-
-        if (events) {
-            const listeners = events[type]
-
-            if (listeners && listeners.length > 0) {
-                for (let i = listeners.length; i--; i > 0) {
-                    if (listeners[i] === listener) {
-                        listeners.splice(i, 1)
-                        break
-                    }
-                }
-            }
-        }
-    }
-
-    dispatchEvent(event = {}) {
-        if (typeof event.preventDefault !== 'function') {
-            event.preventDefault = () => {}
-        }
-        if (typeof event.stopPropagation !== 'function') {
-            event.stopPropagation = () => {}
-        }
-        const listeners = _events.get(this)[event.type]
-
-        if (listeners) {
-            for (let i = 0; i < listeners.length; i++) {
-                listeners[i](event)
-            }
-        }
-    }
-
-    dispatchTouchEvent(e = {}) {
-        const target = {
-            ...this
-        }
-
-        const event = {
-            changedTouches: e.changedTouches.map(touch => new Touch(touch)),
-            touches: e.touches.map(touch => new Touch(touch)),
-            targetTouches: Array.prototype.slice.call(e.touches.map(touch => new Touch(touch))),
-            timeStamp: e.timeStamp,
-            target: target,
-            currentTarget: target,
-            type: e.type,
-            cancelBubble: false,
-            cancelable: false
-        }
-
-        this.dispatchEvent(event)
-    }
-}
+const _events = new WeakMap()
+
+class Touch {
+    constructor(touch) {
+        // CanvasTouch{identifier, x, y}
+        // Touch{identifier, pageX, pageY, clientX, clientY, force}
+        this.identifier = touch.identifier
+
+        this.force = touch.force === undefined ? 1 : touch.force
+        this.pageX = touch.pageX || touch.x
+        this.pageY = touch.pageY || touch.y
+        this.clientX = touch.clientX || touch.x
+        this.clientY = touch.clientY || touch.y
+
+        this.screenX = this.pageX
+        this.screenY = this.pageY
+    }
+}
+
+export default class EventTarget {
+    constructor() {
+        _events.set(this, {})
+    }
+
+    addEventListener(type, listener, options = {}) {
+        let events = _events.get(this)
+
+        if (!events) {
+            events = {}
+            _events.set(this, events)
+        }
+        if (!events[type]) {
+            events[type] = []
+        }
+        events[type].push(listener)
+
+        if (options.capture) {
+            // console.warn('EventTarget.addEventListener: options.capture is not implemented.')
+        }
+        if (options.once) {
+            // console.warn('EventTarget.addEventListener: options.once is not implemented.')
+        }
+        if (options.passive) {
+            // console.warn('EventTarget.addEventListener: options.passive is not implemented.')
+        }
+    }
+
+    removeEventListener(type, listener) {
+        const events = _events.get(this)
+
+        if (events) {
+            const listeners = events[type]
+
+            if (listeners && listeners.length > 0) {
+                for (let i = listeners.length; i--; i > 0) {
+                    if (listeners[i] === listener) {
+                        listeners.splice(i, 1)
+                        break
+                    }
+                }
+            }
+        }
+    }
+
+    dispatchEvent(event = {}) {
+        if (typeof event.preventDefault !== 'function') {
+            event.preventDefault = () => {}
+        }
+        if (typeof event.stopPropagation !== 'function') {
+            event.stopPropagation = () => {}
+        }
+        const listeners = _events.get(this)[event.type]
+
+        if (listeners) {
+            for (let i = 0; i < listeners.length; i++) {
+                listeners[i](event)
+            }
+        }
+    }
+
+    dispatchTouchEvent(e = {}) {
+        const target = {
+            ...this
+        }
+
+        const event = {
+            changedTouches: e.changedTouches.map(touch => new Touch(touch)),
+            touches: e.touches.map(touch => new Touch(touch)),
+            targetTouches: Array.prototype.slice.call(e.touches.map(touch => new Touch(touch))),
+            timeStamp: e.timeStamp,
+            target: target,
+            currentTarget: target,
+            type: e.type,
+            cancelBubble: false,
+            cancelable: false
+        }
+
+        this.dispatchEvent(event)
+    }
+}