Move buffer.slice polyfill into separate function.

blueimp · blueimp · commit 14fc0d3cb315 · 2020-04-30T01:35:30.000+09:00
diff --git a/js/load-image-meta.js b/js/load-image-meta.js
@@ -35,6 +35,18 @@
       Blob.prototype.webkitSlice ||
       Blob.prototype.mozSlice)
 
+  loadImage.bufferSlice =
+    loadImage.global.ArrayBuffer.prototype.slice ||
+    function (begin, end) {
+      // Polyfill for IE10, which does not support ArrayBuffer.slice
+      // eslint-disable-next-line no-param-reassign
+      end = end || this.byteLength - begin
+      var arr1 = new Uint8Array(this, begin, end)
+      var arr2 = new Uint8Array(end)
+      arr2.set(arr1)
+      return arr2.buffer
+    }
+
   loadImage.metaDataParsers = {
     jpeg: {
       0xffe1: [], // APP1 marker
@@ -89,8 +101,6 @@
           var markerLength
           var parsers
           var i
-          var arr1
-          var arr2
           // Check for the JPEG marker (0xffd8):
           if (dataView.getUint16(0) === 0xffd8) {
             while (offset < maxOffset) {
@@ -136,16 +146,7 @@
             // Meta length must be longer than JPEG marker (2)
             // plus APPn marker (2), followed by length bytes (2):
             if (!options.disableImageHead && headLength > 6) {
-              if (buffer.slice) {
-                data.imageHead = buffer.slice(0, headLength)
-              } else {
-                // Workaround for IE10, which does not support
-                // ArrayBuffer.slice:
-                arr1 = new Uint8Array(buffer, 0, headLength)
-                arr2 = new Uint8Array(headLength)
-                arr2.set(arr1)
-                data.imageHead = arr2.buffer
-              }
+              data.imageHead = loadImage.bufferSlice.call(buffer, 0, headLength)
             }
           } else {
             // eslint-disable-next-line no-console
