JavaScript file highlight for Prism.js (support function arguments)

prism-javascript.js

// current

Prism.languages.javascript = Prism.languages.extend('clike', {
	'keyword': /\b(?:as|async|await|break|case|catch|class|const|continue|debugger|default|delete|do|else|enum|export|extends|finally|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/,
	'number': /\b(?:0[xX][\dA-Fa-f]+|0[bB][01]+|0[oO][0-7]+|NaN|Infinity)\b|(?:\b\d+\.?\d*|\B\.\d+)(?:[Ee][+-]?\d+)?/,
	// Allow for all non-ASCII characters (See http://stackoverflow.com/a/2008444)
	'function': /[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?=\s*\()/i,
	'operator': /-[-=]?|\+[+=]?|!=?=?|<<?=?|>>?>?=?|=(?:==?|>)?|&[&=]?|\|[|=]?|\*\*?=?|\/=?|~|\^=?|%=?|\?|\.{3}/
});

Prism.languages.insertBefore('javascript', 'keyword', {
	'regex': {
		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s])\s*)\/(\[[^\]\r\n]+]|\\.|[^/\\\[\r\n])+\/[gimyu]{0,5}(?=\s*($|[\r\n,.;})]))/,
		lookbehind: true,
		greedy: true
	},
	// This must be declared before keyword because we use "function" inside the look-forward
	'function-variable': {
		pattern: /([_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*|(?<=\W))?(\s*=?\s*(function\s*\([^()]*\)|(\([^()]*\)|[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*)\s*=>))/i,
		alias: 'function',
		inside: {
			'argument': {
				pattern: /((?<=\()[^()]*(?=\)))|((?<=\b)[^()\s]*?(?=\s*=>))/,
				inside: {
					rest: Prism.languages.javascript
				}
			},
			rest: Prism.languages.javascript
		}
	},
	'function-declaration': {
		pattern: /(?<=(\s|\/|^))[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?<!(if|else|for|while|switch))\b.*?\((.*?[^\)])?\)[^)\w]*?\{/,
		alias: 'function',
		inside: {
			'argument': {
				pattern: /((?<=\()[^()]*(?=\)))|((?<=\b)[^()\s]*?(?=\s*=>))/,
				inside: {
					rest: Prism.languages.javascript
				}
			},
			rest: Prism.languages.javascript
		}
	},
	'constant': /\b[A-Z][A-Z\d_]*\b/
});

Prism.languages.insertBefore('javascript', 'string', {
	'template-string': {
		pattern: /`(?:\\[\s\S]|[^\\`])*`/,
		greedy: true,
		inside: {
			'interpolation': {
				pattern: /\$\{[^}]+\}/,
				inside: {
					'interpolation-punctuation': {
						pattern: /^\$\{|\}$/,
						alias: 'punctuation'
					},
					rest: Prism.languages.javascript
				}
			},
			'string': /[\s\S]+/
		}
	}
});

if (Prism.languages.markup) {
	Prism.languages.insertBefore('markup', 'tag', {
		'script': {
			pattern: /(<script[\s\S]*?>)[\s\S]*?(?=<\/script>)/i,
			lookbehind: true,
			inside: Prism.languages.javascript,
			alias: 'language-javascript',
			greedy: true
		}
	});
}

Prism.languages.js = Prism.languages.javascript;