test_css-logic-specificity.html

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<!DOCTYPE HTML>

<html>

<!--

Test that css-logic calculates CSS specificity properly

-->

<meta charset="utf-8">

<title>Test css-logic specificity</title>

<script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>

<body style="background:blue;">

<script>

  "use strict";

  window.onload = function() {

    const {require} = ChromeUtils.importESModule("resource://devtools/shared/loader/Loader.sys.mjs");

    const {CssLogic, CssSelector} = require("devtools/server/actors/inspector/css-logic");

    const TEST_DATA = [

      {text: "*", expected: 0},

      {text: "LI", expected: 1},

      {text: "UL LI", expected: 2},

      {text: "UL OL + LI", expected: 3},

      {text: "H1 + [REL=\"up\"]", expected: 1025},

      {text: "UL OL LI.red", expected: 1027},

      {text: "LI.red.level", expected: 2049},

      {text: ".red .level", expected: 2048},

      {text: "#x34y", expected: 1048576},

      {text: "#s12:not(FOO)", expected: 1048577},

      {text: "body#home div#warning p.message", expected: 2098179},

      {text: "* body#home div#warning p.message", expected: 2098179},

      {text: "#footer :not(nav) li", expected: 1048578},

      {text: "bar:nth-child(n)", expected: 1025},

      {text: "li::marker", expected: 2},

      {text: "a:hover", expected: 1025},

];

    function createDocument() {

      let text = TEST_DATA.map(i=>i.text).join(",");

      text = '<style>' + text + " {color:red;}</style>";

      document.body.innerHTML = text;

    function getExpectedSpecificity(selectorText) {

      return TEST_DATA.filter(i => i.text === selectorText)[0].expected;

    SimpleTest.waitForExplicitFinish();

    createDocument();

    const cssLogic = new CssLogic();

    cssLogic.highlight(document.body);

    // There could be more stylesheets due to e.g, accessiblecaret, so find the

    // right one.

    info(`Sheets: ${cssLogic.sheets.map(s => s.href).join(", ")}`);

    const cssSheet = cssLogic.sheets.find(s => s.href == location.href);

    const cssRule = cssSheet.domSheet.cssRules[0];

    const selectors = CssLogic.getSelectors(cssRule);

    is(selectors.length, TEST_DATA.length, "Should be the right rule");

    info("Iterating over the test selectors: " + selectors.join(", "));

    for (let i = 0; i < selectors.length; i++) {

      const selectorText = selectors[i];

      info("Testing selector " + selectorText);

      const selector = new CssSelector(cssRule, selectorText, i);

      const expected = getExpectedSpecificity(selectorText);

      const specificity = selector.cssRule.selectorSpecificityAt(selector.selectorIndex);

      is(specificity, expected,

        'Selector "' + selectorText + '" has a specificity of ' + expected);

    info("Testing specificity of element.style");

    const colorProp = cssLogic.getPropertyInfo("background");

    is(colorProp.matchedSelectors[0].specificity, 0x40000000,

       "Element styles have specificity of 0x40000000 (1073741824).");

    SimpleTest.finish();

};

  </script>

</body>

</html>