fix: handle pull requests (#56)

Author: jimmywarting

example/sw.js

@@ -1,3 +1,6 @@
+// Want to remove this postMessage hack, tell them u want transferable streams:
+// https://bugs.webkit.org/show_bug.cgi?id=215485
+
 const WRITE = 0
 const PULL = 0
 const ERROR = 1
@@ -24,6 +27,10 @@ class MessagePortSource {
     this.controller = controller
   }
 
+  pull () {
+    this.port.postMessage({ type: PULL })
+  }
+
   /** @param {Error} reason */
   cancel (reason) {
     // Firefox can notify a cancel event, chrome can't
@@ -37,7 +44,6 @@ class MessagePortSource {
     // enqueue() will call pull() if needed when there's no backpressure
     if (message.type === WRITE) {
       this.controller.enqueue(message.chunk)
-      this.port.postMessage({ type: PULL })
     }
     if (message.type === ABORT) {
       this.controller.error(message.reason)

src/adapters/downloader.js

@@ -9,8 +9,8 @@ const {
 } = config
 
 const { GONE } = errors
-// @ts-ignore
-const isSafari = /constructor/i.test(window.HTMLElement) || window.safari || window.WebKitPoint
+// @ts-ignore - Don't match newer versions of Safari, but that's okay
+const isOldSafari = /constructor/i.test(window.HTMLElement)
 
 export class FileHandle {
   constructor (name = 'unkown') {
@@ -37,7 +37,7 @@ export class FileHandle {
 
     link.download = this.name
 
-    if (isSafari || !sw) {
+    if (isOldSafari || !sw) {
       /** @type {Blob[]} */
       let chunks = []
       ts.readable.pipeTo(new WritableStream({
@@ -93,6 +93,9 @@ export class FileHandle {
   }
 }
 
+// Want to remove this postMessage hack, tell them u want transferable streams:
+// https://bugs.webkit.org/show_bug.cgi?id=215485
+
 const WRITE = 0
 const PULL = 0
 const ERROR = 1