css_loading.ejs

if (typeof document === "undefined") return;
// Scopes the chunk-identity attribute used to find a currently installed stylesheet
// (see extractCssFindStylesheet) to this compilation, so two independently compiled
// apps sharing a chunk id on the same page can't steal or remove each other's
// stylesheet. Matches the same output.uniqueName-based identity scheme chunk/module
// script loading already uses (see load_script.ejs).
var extractCssUniquePrefix = <%- _unique_name_prefix %>;
var extractCssCreateStylesheet = function (
	chunkId, fullhref, oldTag, resolve, reject, fetchPriority
) {
	<%- _create_link %>
	var onLinkComplete = function (event) {
		// avoid mem leaks.
		linkTag.onerror = linkTag.onload = null;
		if (event.type === 'load') {
			resolve();
		} else {
			var errorType = event && (event.type === 'load' ? 'missing' : event.type);
			var realHref = event && event.target && event.target.href || fullhref;
			var err = new Error("Loading CSS chunk " + chunkId + " failed.\\n(" + realHref + ")");
			err.code = "CSS_CHUNK_LOAD_FAILED";
			err.type = errorType;
			err.request = realHref;
			if (linkTag.parentNode) linkTag.parentNode.removeChild(linkTag)
			reject(err);
		}
	}
	linkTag.onerror = linkTag.onload = onLinkComplete;
	<%- _insert %>
	return linkTag;
}
var extractCssFindStylesheet = function (href, fullhref, chunkId) {
	var existingLinkTags = document.getElementsByTagName("link");
	for (var i = 0; i < existingLinkTags.length; i++) {
		var tag = existingLinkTags[i];
		// When a chunkId is given (HMR replacement lookup), prefer matching the tag that
		// was created for that chunk: the href it was created with may since have changed
		// (e.g. a hashed filename), so it can no longer be found by comparing hrefs.
		if (chunkId !== undefined && tag.getAttribute("data-webpack-chunk") === extractCssUniquePrefix + String(chunkId)) {
			return tag;
		}
		var dataHref = tag.getAttribute("data-href") || tag.getAttribute("href");
		if (dataHref) {
			dataHref = dataHref.split('?')[0]
		}
		if (tag.rel === "stylesheet" && (dataHref === href || dataHref === fullhref)) return tag;
	}

	var existingStyleTags = document.getElementsByTagName("style");
	for (var i = 0; i < existingStyleTags.length; i++) {
		var tag = existingStyleTags[i];
		var dataHref = tag.getAttribute("data-href");
		if (dataHref === href || dataHref === fullhref) return tag;
	}
}

var extractCssLoadStylesheet = function (chunkId, fetchPriority) {
	return new Promise(function (resolve, reject) {
		/**
			A chunk that hasn't been loaded yet (e.g. a lazy route not imported so far) has
			no tag for the HMR handler to update, so it instead just retains the fresh
			filename it learned about (see HMR_MINI_CSS_FILENAMES in the with-hmr runtime).
			Consult that retained mapping here too, or loading the chunk for the first time
			after its CSS changed would still request the stale, pre-edit filename.
		 */
		var miniCssFilenames = <%- weak(HMR_MINI_CSS_FILENAMES) %>;
		var href = (miniCssFilenames && miniCssFilenames[chunkId]) || <%- REQUIRE_SCOPE %>.miniCssF(chunkId);
		var fullhref = <%- PUBLIC_PATH %> + href;
		if (extractCssFindStylesheet(href, fullhref)) return resolve();
		extractCssCreateStylesheet(chunkId, fullhref, null, resolve, reject, fetchPriority);
	})
}