60 lines
1.8 KiB
JavaScript
60 lines
1.8 KiB
JavaScript
"use strict";
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{
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// private variables are defined with `const` so they don't leak outside this block statement
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const IFRAME_DEFAULT_SIZE = "200";
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const iframes = new WeakMap();
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// helpers are defined with `var` so they are globally accessible
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var createMQL = async t => {
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const iframe = await createIFrame(t);
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const mql = iframe.contentWindow.matchMedia(`(max-width: ${IFRAME_DEFAULT_SIZE}px)`);
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assert_true(mql.matches, "MQL should match on newly created <iframe>");
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iframes.set(mql, iframe);
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return mql;
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};
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var createIFrame = (t, width = IFRAME_DEFAULT_SIZE, height = width) => {
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assert_not_equals(document.body, null, "<body> element is missing");
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const iframe = document.createElement("iframe");
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iframe.srcdoc = "";
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iframe.width = String(width);
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iframe.height = String(height);
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iframe.style.border = "none";
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t.add_cleanup(() => {
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document.body.removeChild(iframe);
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});
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return new Promise(resolve => {
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iframe.addEventListener("load", () => {
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iframe.contentDocument.body.offsetWidth; // reflow
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resolve(iframe);
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});
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document.body.appendChild(iframe);
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});
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};
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var triggerMQLEvent = mql => {
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const iframe = iframes.get(mql);
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assert_not_equals(iframe, undefined, "Passed MQL instance was not created with createMQL");
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iframe.width = iframe.width === IFRAME_DEFAULT_SIZE ? "250" : IFRAME_DEFAULT_SIZE;
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};
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var getWindow = mql => {
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const iframe = iframes.get(mql);
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assert_not_equals(iframe, undefined, "Passed MQL instance was not created with createMQL");
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return iframe.contentWindow;
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};
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var waitForChangesReported = () => {
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return new Promise(resolve => {
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requestAnimationFrame(() => {
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requestAnimationFrame(resolve);
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});
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});
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};
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}
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