refactor: use setInterval to check style is loaded in old webkit browser

Author: gaterking

src/index.js

@@ -338,11 +338,22 @@ class MiniCssExtractPlugin {
                   ]),
                   '}',
                   'var linkTag = document.createElement("link");',
-                  'var isOldWebKit = Number(navigator.userAgent.replace(/.*AppleWebKit\\/(\\d+)..*/, "$1")) < 536;',
                   'linkTag.rel = "stylesheet";',
                   'linkTag.type = "text/css";',
-                  'if (!isOldWebKit) {',
-                  'linkTag.onload = resolve;',
+                  'linkTag.href = fullhref;',
+                  "// old webkit's would claim to have onload, but didn't really support it",
+                  '// https://github.com/kriszyp/xstyle/blob/master/core/load-css.js',
+                  'var webkitVersion = navigator.userAgent.match(/AppleWebKit\\/(\\d+\\.?\\d*)/);',
+                  'webkitVersion = webkitVersion && +webkitVersion[1];',
+                  'if(linkTag.onload === null && !(webkitVersion < 536)){',
+                  '// most browsers support this onload function now',
+                  'linkTag.onload = function(){',
+                  '// cleanup',
+                  'linkTag.onload = null;',
+                  'linkTag.onerror = null;',
+                  'resolve();',
+                  '};',
+                  '// always add the error handler, so we can notify of any errors',
                   'linkTag.onerror = function(event) {',
                   Template.indent([
                     'var request = event && event.target && event.target.src || fullhref;',
@@ -351,11 +362,27 @@ class MiniCssExtractPlugin {
                     'reject(err);',
                   ]),
                   '};',
+                  '} else {',
+                  'var errorTimeout = 60000;',
+                  'var startTime = Date.now();',
+                  'var interval = setInterval(function(){',
+                  'if(linkTag.style){',
+                  'clearInterval(interval);',
+                  'resolve();',
+                  '}',
+                  'if(!linkTag.style && (Date.now() - startTime) > errorTimeout){',
+                  Template.indent([
+                    'var request = fullhref;',
+                    'var err = new Error("Loading CSS chunk " + chunkId + " timeout in old browser.\\n(" + request + ")");',
+                    'err.request = request;',
+                    'clearInterval(interval);',
+                    'reject(err);',
+                  ]),
+                  '}',
+                  '}, 25);',
                   '}',
-                  'linkTag.href = fullhref;',
                   'var head = document.getElementsByTagName("head")[0];',
                   'head.appendChild(linkTag);',
-                  'if (isOldWebKit) { resolve();}',
                 ]),
                 '}).then(function() {',
                 Template.indent(['installedCssChunks[chunkId] = 0;']),