63 lines
2.4 KiB
JavaScript
63 lines
2.4 KiB
JavaScript
function attributeEntryToString(attribute, context) {
|
|
let [key, value] = attribute;
|
|
|
|
if (typeof value === "function") { // Callback must return a string or a number
|
|
value = value(context); // Run the provided callback and store the result
|
|
}
|
|
|
|
if (typeof value !== "string" && typeof value !== "number") {
|
|
throw new Error(
|
|
`Attribute "${key}" must have, or evaluate to, a value of type string or number, not "${typeof value}".`
|
|
);
|
|
}
|
|
|
|
return `${key}="${value}"`;
|
|
}
|
|
|
|
/**
|
|
* ## Usage
|
|
* The function `getAttributes` is used to convert an object, `attributes`, with HTML attributes as keys and the values as the corresponding HTML attribute's values.
|
|
* If it is falsey, an empty string will be returned.
|
|
*
|
|
* ```js
|
|
getAttributes({
|
|
tabindex: 0,
|
|
'data-language': function (context) { return context.language; },
|
|
'data-otherStuff': 'value'
|
|
}) // => ' tabindex="0" data-language="JavaScript" data-otherStuff="value"'
|
|
```
|
|
*
|
|
* @param {{[s: string]: string | number}} attributes An object with key-value pairs that represent attributes.
|
|
* @param {object} context An object with the current context.
|
|
* @param {string} context.content The code to parse and highlight.
|
|
* @param {string} context.language The language for the current instance.
|
|
* @param {object} context.options The options passed to the syntax highlighter.
|
|
* @returns {string} A string containing the above HTML attributes preceded by a single space.
|
|
*/
|
|
function getAttributes(attributes, context = {}) {
|
|
let langClass = context.language ? `language-${context.language}` : "";
|
|
|
|
if (!attributes) {
|
|
return langClass ? ` class="${langClass}"` : "";
|
|
} else if (typeof attributes === "object") {
|
|
if(!("class" in attributes) && langClass) {
|
|
// class attribute should be first in order
|
|
let tempAttrs = { class: langClass };
|
|
for(let key in attributes) {
|
|
tempAttrs[key] = attributes[key];
|
|
}
|
|
attributes = tempAttrs;
|
|
}
|
|
|
|
const formattedAttributes = Object.entries(attributes).map(
|
|
entry => attributeEntryToString(entry, context)
|
|
);
|
|
|
|
return formattedAttributes.length ? ` ${formattedAttributes.join(" ")}` : "";
|
|
} else if (typeof attributes === "string") {
|
|
throw new Error("Syntax highlighter plugin custom attributes on <pre> and <code> must be an object. Received: " + JSON.stringify(attributes));
|
|
}
|
|
}
|
|
|
|
module.exports = getAttributes;
|