Fix Confetti end event after dispose, stalled frame without a 2D context and canvas width (#3228)

.changeset/fix-confetti-dispose-context-width.md

@@ -0,0 +1,5 @@
+---
+"@tabler/core": patch
+---
+
+Fixed `Confetti` firing `end` after `dispose()`, stalling without a 2D context and sizing its canvas with the scrollbar width.

core/js/src/confetti.ts

@@ -59,6 +59,8 @@ type Emitter = {
   stopped: boolean
   /** every piece has landed and `end` was fired */
   done: boolean
+  /** the instance was disposed: the pieces still land, but `end` is not fired */
+  detached: boolean
 }
 
 /**
@@ -134,14 +136,21 @@ const stage = {
   frame: 0,
   lastTick: 0,
 
-  add(emitter: Emitter): void {
+  add(emitter: Emitter): boolean {
-    this.emitters.push(emitter)
     this._mount()
 
+    if (!this.context) {
+      return false
+    }
+
+    this.emitters.push(emitter)
+
     if (!this.frame) {
       this.lastTick = performance.now()
       this.frame = requestAnimationFrame((now) => this._tick(now))
     }
+
+    return true
   },
 
   _mount(): void {
@@ -162,9 +171,14 @@ const stage = {
       display: 'block',
     })
 
+    const context = canvas.getContext('2d')
+    if (!context) {
+      return
+    }
+
     document.body.append(canvas)
     this.canvas = canvas
-    this.context = canvas.getContext('2d')
+    this.context = context
     this._resize()
     window.addEventListener('resize', this._onResize)
   },
@@ -192,7 +206,7 @@ const stage = {
     // The backing store is scaled for HiDPI screens; the CSS size above keeps
     // the element at the viewport size, so the drawing stays sharp and 1:1.
     const dpr = Math.min(window.devicePixelRatio || 1, MAX_DPR)
-    this.canvas.width = window.innerWidth * dpr
+    this.canvas.width = document.documentElement.clientWidth * dpr
     this.canvas.height = window.innerHeight * dpr
     this.context.setTransform(dpr, 0, 0, dpr, 0, 0)
   },
@@ -313,7 +327,10 @@ const stage = {
 
       this.emitters.splice(i, 1)
       emitter.done = true
-      EventHandler.trigger(emitter.element, EVENT_END)
+
+      if (!emitter.detached) {
+        EventHandler.trigger(emitter.element, EVENT_END)
+      }
     }
   },
 }
@@ -373,9 +390,13 @@ class Confetti extends BaseComponent {
       emitted: 0,
       stopped: false,
       done: false,
+      detached: false,
     }
 
-    stage.add(this._emitter)
+    if (!stage.add(this._emitter)) {
+      this._emitter = null
+      EventHandler.trigger(this._element, EVENT_END)
+    }
   }
 
   stop(): void {
@@ -387,6 +408,10 @@ class Confetti extends BaseComponent {
   }
 
   dispose(): void {
+    if (this._emitter) {
+      this._emitter.detached = true
+    }
+
     this.stop()
     super.dispose()
   }

core/js/tests/unit/confetti.spec.ts

@@ -100,6 +100,51 @@ describe('Confetti', () => {
       expect(canvas()).toBeNull()
       expect(end).toHaveBeenCalledTimes(1)
     })
+
+    it('should end at once without a canvas when there is no 2D context', () => {
+      fixtureEl.innerHTML = '<button type="button"></button>'
+      reduceMotion(false)
+      vi.spyOn(HTMLCanvasElement.prototype, 'getContext').mockReturnValue(null)
+
+      const end = vi.fn()
+      button().addEventListener('end.bs.confetti', end)
+      new Confetti(button(), QUICK).burst()
+
+      expect(canvas()).toBeNull()
+      expect(end).toHaveBeenCalledTimes(1)
+    })
+
+    it('should size the backing store to the viewport without the scrollbar', () => {
+      fixtureEl.innerHTML = '<button type="button"></button>'
+      reduceMotion(false)
+      document.documentElement.style.overflowY = 'scroll'
+
+      try {
+        new Confetti(button(), QUICK).burst()
+
+        const dpr = Math.min(window.devicePixelRatio || 1, 2)
+        expect(canvas()!.width).toBe(document.documentElement.clientWidth * dpr)
+      } finally {
+        document.documentElement.style.overflowY = ''
+      }
+    })
+  })
+
+  describe('dispose', () => {
+    it('should not fire end once the instance is disposed', async () => {
+      fixtureEl.innerHTML = '<button type="button"></button>'
+      reduceMotion(false)
+
+      const end = vi.fn()
+      button().addEventListener('end.bs.confetti', end)
+
+      const instance = new Confetti(button(), QUICK)
+      instance.burst()
+      instance.dispose()
+
+      await vi.waitFor(() => expect(canvas()).toBeNull(), { timeout: 3000 })
+      expect(end).not.toHaveBeenCalled()
+    })
   })
 
   describe('stop', () => {