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-rw-r--r--ext/js/dom/sandbox/css-style-applier.js69
1 files changed, 53 insertions, 16 deletions
diff --git a/ext/js/dom/sandbox/css-style-applier.js b/ext/js/dom/sandbox/css-style-applier.js
index 9952fa7d..a6938d92 100644
--- a/ext/js/dom/sandbox/css-style-applier.js
+++ b/ext/js/dom/sandbox/css-style-applier.js
@@ -21,11 +21,17 @@
*/
class CssStyleApplier {
/**
+ * A CSS rule.
* @typedef {object} CssRule
* @property {string} selectors A CSS selector string representing one or more selectors.
- * @property {[string, string][]} styles A list of CSS property and value pairs.
- * @property {string} styles[][0] The CSS property.
- * @property {string} styles[][1] The CSS value.
+ * @property {CssDeclaration[]} styles A list of CSS property and value pairs.
+ */
+
+ /**
+ * A single CSS property declaration.
+ * @typedef {object} CssDeclaration
+ * @property {string} property A CSS property's name, using kebab-case.
+ * @property {string} value The property's value.
*/
/**
@@ -54,14 +60,24 @@ class CssStyleApplier {
* Loads the data file for use.
*/
async prepare() {
- let styleData;
+ let rawData;
try {
- styleData = await this._fetchJsonAsset(this._styleDataUrl);
+ rawData = await this._fetchJsonAsset(this._styleDataUrl);
} catch (e) {
console.error(e);
}
- if (Array.isArray(styleData)) {
- this._styleData = styleData;
+ const styleData = this._styleData;
+ styleData.length = 0;
+ for (const {selectors, styles} of rawData) {
+ const selectors2 = selectors.join(',');
+ const styles2 = [];
+ for (const [property, value] of styles) {
+ styles2.push({property, value});
+ }
+ styleData.push({
+ selectors: selectors2,
+ styles: styles2
+ });
}
}
@@ -76,8 +92,8 @@ class CssStyleApplier {
const className = element.getAttribute('class');
if (className.length === 0) { continue; }
let cssTextNew = '';
- for (const {selectorText, styles} of this._getCandidateCssRulesForClass(className)) {
- if (!element.matches(selectorText)) { continue; }
+ for (const {selectors, styles} of this._getCandidateCssRulesForClass(className)) {
+ if (!element.matches(selectors)) { continue; }
cssTextNew += this._getCssText(styles);
}
cssTextNew += element.style.cssText;
@@ -95,6 +111,12 @@ class CssStyleApplier {
// Private
+ /**
+ * Fetches and parses a JSON file.
+ * @param {string} url The URL to the file.
+ * @returns {Promise<*>} A JSON object.
+ * @throws {Error} An error is thrown if the fetch fails.
+ */
async _fetchJsonAsset(url) {
const response = await fetch(url, {
method: 'GET',
@@ -124,37 +146,52 @@ class CssStyleApplier {
const classList = this._getTokens(className);
for (const {selectors, styles} of this._styleData) {
- const selectorText = selectors.join(',');
- if (!this._selectorMatches(selectorText, classList)) { continue; }
- rules.push({selectorText, styles});
+ if (!this._selectorMightMatch(selectors, classList)) { continue; }
+ rules.push({selectors, styles});
}
return rules;
}
+ /**
+ * Converts an array of CSS rules to a CSS string.
+ * @param {CssRule[]} styles An array of CSS rules.
+ * @returns {string} The CSS string.
+ */
_getCssText(styles) {
let cssText = '';
- for (const [property, value] of styles) {
+ for (const {property, value} of styles) {
cssText += `${property}:${value};`;
}
return cssText;
}
- _selectorMatches(selectorText, classList) {
+ /**
+ * Checks whether or not a CSS string might match at least one class in a list.
+ * @param {string} selectors A CSS selector string.
+ * @param {string[]} classList An array of CSS classes.
+ * @returns {boolean} `true` if the selector string might match one of the classes in `classList`, false otherwise.
+ */
+ _selectorMightMatch(selectors, classList) {
const pattern = this._patternClassNameCharacter;
for (const item of classList) {
const prefixedItem = `.${item}`;
let start = 0;
while (true) {
- const index = selectorText.indexOf(prefixedItem, start);
+ const index = selectors.indexOf(prefixedItem, start);
if (index < 0) { break; }
start = index + prefixedItem.length;
- if (start >= selectorText.length || !pattern.test(selectorText[start])) { return true; }
+ if (start >= selectors.length || !pattern.test(selectors[start])) { return true; }
}
}
return false;
}
+ /**
+ * Gets the whitespace-delimited tokens from a string.
+ * @param {string} tokenListString The string to parse.
+ * @returns {string[]} An array of tokens.
+ */
_getTokens(tokenListString) {
let start = 0;
const pattern = this._patternHtmlWhitespace;