Match selectors without using css-select where possible. (#19)

* Do simple matches without external module.
* Updated test case.

lib/css.js

@@ -99,6 +99,8 @@ export class CSSRule {
   #specificity;
   #declarations;
   #isInMediaQuery;
+  /** @type {(function(XastElement):boolean)|undefined} */
+  #matcher;
 
   /**
    * @param {CSSSelector} selector
@@ -111,6 +113,7 @@ export class CSSRule {
     this.#specificity = specificity;
     this.#declarations = declarations;
     this.#isInMediaQuery = isInMediaQuery;
+    this.#matcher = this.#initMatcher();
   }
 
   /**
@@ -197,10 +200,44 @@ export class CSSRule {
     return this.#selector.hasPseudos();
   }
 
+  /**
+   * @returns {(function(XastElement):boolean)|undefined}
+   */
+  #initMatcher() {
+    const sequences = this.#selector.getSequences();
+    if (sequences.length > 1) {
+      return;
+    }
+    const simpleSelectors = sequences[0].getSelectors();
+    if (simpleSelectors.length > 1) {
+      return;
+    }
+    switch (simpleSelectors[0].type) {
+      case 'ClassSelector':
+        return (element) =>
+          element.attributes.class === simpleSelectors[0].name;
+      case 'IdSelector':
+        return (element) => element.attributes.id === simpleSelectors[0].name;
+      case 'TypeSelector':
+        return (element) => element.name === simpleSelectors[0].name;
+    }
+  }
+
   isInMediaQuery() {
     return this.#isInMediaQuery;
   }
 
+  /**
+   * @param {XastElement} element
+   * @return {boolean|null}
+   */
+  _matches(element) {
+    if (this.#matcher !== undefined) {
+      return this.#matcher(element);
+    }
+    return null;
+  }
+
   /**
    * @param {XastElement} element
    * @return {boolean}
@@ -281,6 +318,10 @@ export class CSSSelector {
     return features;
   }
 
+  getSequences() {
+    return this.#selectorSequences;
+  }
+
   getString() {
     return this.#str;
   }
@@ -374,6 +415,10 @@ export class CSSSelectorSequence {
     return ids;
   }
 
+  getSelectors() {
+    return this.#simpleSelectors;
+  }
+
   /**
    * @param {boolean} includePseudos
    */

lib/style-css-tree.js

@@ -31,6 +31,11 @@ class CSSRuleConcrete extends CSSRule {
    */
   matches(element) {
     if (!this.#compiledSelector) {
+      // Try to do a simple match with the rule.
+      const result = super._matches(element);
+      if (result !== null) {
+        return result;
+      }
       this.#compiledSelector = CSSselect.compile(
         this.getSelectorStringWithoutPseudos(),
         SELECT_OPTIONS,

test/lib/css.rule.match.test.js

@@ -0,0 +1,75 @@
+import { CSSRule, CSSSelector, CSSSelectorSequence } from '../../lib/css.js';
+import { createElement } from './testutils.js';
+
+/**
+ * @typedef {import('../../lib/css.js').SimpleSelector} SimpleSelector
+ */
+
+describe('test parsing and stringifying of selectors', function () {
+  /** @type {{
+   * selectorInfo:SimpleSelector[],
+   * elData:{elName:string,atts:[string,string][]},
+   * expected:boolean|null
+   * }[]} */
+  const tests = [
+    {
+      selectorInfo: [{ type: 'ClassSelector', name: 'class1' }],
+      elData: { elName: 'path', atts: [] },
+      expected: false,
+    },
+    {
+      selectorInfo: [{ type: 'ClassSelector', name: 'class1' }],
+      elData: { elName: 'path', atts: [['class', 'class2']] },
+      expected: false,
+    },
+    {
+      selectorInfo: [{ type: 'ClassSelector', name: 'class1' }],
+      elData: { elName: 'path', atts: [['class', 'class1']] },
+      expected: true,
+    },
+    {
+      selectorInfo: [
+        { type: 'ClassSelector', name: 'class1' },
+        { type: 'IdSelector', name: 'id1' },
+      ],
+      elData: { elName: 'path', atts: [['class', 'class1']] },
+      expected: null,
+    },
+    {
+      selectorInfo: [{ type: 'IdSelector', name: 'id1' }],
+      elData: { elName: 'path', atts: [] },
+      expected: false,
+    },
+    {
+      selectorInfo: [{ type: 'IdSelector', name: 'id1' }],
+      elData: { elName: 'path', atts: [['id', 'id1']] },
+      expected: true,
+    },
+    {
+      selectorInfo: [{ type: 'IdSelector', name: 'id1' }],
+      elData: { elName: 'path', atts: [['id', 'class1']] },
+      expected: false,
+    },
+    {
+      selectorInfo: [{ type: 'TypeSelector', name: 'path' }],
+      elData: { elName: 'path', atts: [] },
+      expected: true,
+    },
+    {
+      selectorInfo: [{ type: 'TypeSelector', name: 'path' }],
+      elData: { elName: 'circle', atts: [] },
+      expected: false,
+    },
+  ];
+  const declarations = new Map();
+
+  for (const test of tests) {
+    const sequences = [new CSSSelectorSequence(undefined, test.selectorInfo)];
+    const selector = new CSSSelector(sequences);
+    it(`test ${selector.getString()}`, function () {
+      const rule = new CSSRule(selector, [0, 0, 0], declarations, false);
+      const element = createElement(test.elData);
+      expect(rule._matches(element)).toBe(test.expected);
+    });
+  }
+});

test/lib/styledata.updatereferencedids.test.js

@@ -16,15 +16,19 @@ test('make sure compiled query cache is cleared correctly when style ids are cha
 
   // Should match to begin with.
   const rules = styleData.getMatchingRules(element);
+  const rule = rules[0];
+  expect(rule._matches(element)).toBe(true);
   expect(rules.length).toBe(1);
 
   // Replace the id in the rules; should no longer match.
   const m = new Map();
   m.set('id1', 'a');
   styleData.updateReferencedIds(styleData.getReferencedIds(), m);
+  expect(rule._matches(element)).toBe(false);
   expect(styleData.getMatchingRules(element).length).toBe(0);
 
   // Change the id of the element; it should match again.
   element.attributes.id = 'a';
+  expect(rule._matches(element)).toBe(true);
   expect(styleData.getMatchingRules(element).length).toBe(1);
 });

test/lib/testutils.js

@@ -3,6 +3,28 @@ import { parseSvg } from '../../lib/parser.js';
 import { getDocData } from '../../lib/docdata.js';
 import { visit } from '../../lib/xast.js';
 
+/**
+ * @param {{elName:string,atts:[string,string][]}} elData
+ * @returns {import('../../lib/types.js').XastElement}
+ */
+export function createElement(elData) {
+  /** @type {import('../../lib/types.js').XastRoot} */
+  const root = { type: 'root', children: [] };
+  /** @type {import('../../lib/types.js').XastElement} */
+  const element = {
+    type: 'element',
+    name: elData.elName,
+    parentNode: root,
+    attributes: {},
+    children: [],
+  };
+  for (const att of elData.atts) {
+    element.attributes[att[0]] = att[1];
+  }
+  root.children.push(element);
+  return element;
+}
+
 /**
  * @param {string} fileName
  */

test/lib/tools.getReferencedIds.test.js

@@ -1,4 +1,5 @@
 import { getReferencedIds } from '../../lib/svgo/tools.js';
+import { createElement } from './testutils.js';
 
 /**
  * @typedef {{
@@ -8,29 +9,6 @@ import { getReferencedIds } from '../../lib/svgo/tools.js';
  * }} TestInfo
  */
 
-/**
- *
- * @param {TestInfo} test
- * @returns {import('../../lib/types.js').XastElement}
- */
-function createElement(test) {
-  /** @type {import('../../lib/types.js').XastRoot} */
-  const root = { type: 'root', children: [] };
-  /** @type {import('../../lib/types.js').XastElement} */
-  const element = {
-    type: 'element',
-    name: test.elName,
-    parentNode: root,
-    attributes: {},
-    children: [],
-  };
-  for (const att of test.atts) {
-    element.attributes[att[0]] = att[1];
-  }
-  root.children.push(element);
-  return element;
-}
-
 describe('getReferencedIds()', () => {
   /**
    * @type {TestInfo[]}