From eb72130f0b6cda58e7d4b148b14124c3cc3819ce Mon Sep 17 00:00:00 2001
From: Tomas Heie <DaxterSpeed@users.noreply.github.com>
Date: Mon, 6 May 2019 16:08:37 +0200
Subject: [PATCH] Refactor lib/parser.js to use ES6 Classes.

This was done mostly automatically with VSCode's refactoring. Some care was put into matching this project's formatting and the resulting dead code was removed.

Additionally since ES6 Classes disallow calling classes without the new keyword the exported object is wrapped in a Proxy to handle that use case.
---
 lib/parser.js | 444 +++++++++++++++++++++++++-------------------------
 1 file changed, 223 insertions(+), 221 deletions(-)

diff --git a/lib/parser.js b/lib/parser.js
index e005d1b..3992c8f 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -2,288 +2,290 @@
 
 const SPACE = /\s/;
 
-const Parser = exports = module.exports = function Parser(options) {
-	if ( ! (this instanceof Parser) )
-		return new Parser(options);
-
-	this.opts = Object.assign({
-		OPEN: '{',
-		CLOSE: '}',
-		SEP: ',',
-		SUB_VAR: '#',
-		ESCAPE: "'",
-		OFFSET: 'offset:',
-
-		subnumeric_types: ['plural', 'selectordinal'],
-		submessage_types: ['plural', 'selectordinal', 'select']
-	}, options)
-}
-
-Parser.prototype.parse = function(msg) {
-	return this.parseAST({msg: String(msg), i: 0}, null);
-}
-
-Parser.prototype.parseAST = function(context, parent) {
-	const msg = context.msg,
-		length = msg.length,
-		special_hash = parent && this.opts.subnumeric_types.includes(parent.t),
-		out = [];
-
-	while ( context.i < length ) {
-		const start = context.i,
-			char = msg[start];
-
-		if ( char === this.opts.CLOSE ) {
-			if ( ! parent )
-				throw unexpected(char, context.i);
-			break;
-
-		} else if ( char === this.opts.OPEN || (special_hash && char === this.opts.SUB_VAR) ) {
-			const element = this.parseElement(context, parent);
-			if ( element )
-				out.push(element);
-
-		} else {
-			const text = this.parseText(context, parent);
-			if ( text )
-				out.push(text);
+class Parser {
+	constructor(options) {
+		this.opts = Object.assign(
+			{
+				OPEN: '{',
+				CLOSE: '}',
+				SEP: ',',
+				SUB_VAR: '#',
+				ESCAPE: "'",
+				OFFSET: 'offset:',
+				subnumeric_types: ['plural', 'selectordinal'],
+				submessage_types: ['plural', 'selectordinal', 'select']
+			},
+			options
+		);
+	}
+	
+	parse(msg) {
+		return this.parseAST({ msg: String(msg), i: 0 }, null);
+	}
+	
+	parseAST(context, parent) {
+		const msg = context.msg,
+			length = msg.length,
+			special_hash =
+				parent && this.opts.subnumeric_types.includes(parent.t),
+			out = [];
+
+		while (context.i < length) {
+			const start = context.i,
+				char = msg[start];
+			if (char === this.opts.CLOSE) {
+				if (!parent) throw unexpected(char, context.i);
+				break;
+			} else if (
+				char === this.opts.OPEN ||
+				(special_hash && char === this.opts.SUB_VAR)
+			) {
+				const element = this.parseElement(context, parent);
+				if (element) out.push(element);
+			} else {
+				const text = this.parseText(context, parent);
+				if (text) out.push(text);
+			}
+
+			// Infinite Loop Protection
+			if (context.i === start) throw unexpected(char, context.i);
 		}
 
-		// Infinite Loop Protection
-		if ( context.i === start )
-			throw unexpected(char, context.i);
+		return out;
 	}
-
-	return out;
-}
-
-Parser.prototype.parseText = function(context, parent, include_separator = true, include_space = true) {
-	const msg = context.msg,
-		length = msg.length,
-		special_hash = parent && this.opts.subnumeric_types.includes(parent.t);
-
-	let out = '';
-
-	while ( context.i < length ) {
-		const char = msg[context.i];
-		if ( char === this.opts.OPEN ||
+	
+	parseText(context, parent, include_separator = true, include_space = true) {
+		const msg = context.msg,
+			length = msg.length,
+			special_hash =
+				parent && this.opts.subnumeric_types.includes(parent.t);
+
+		let out = '';
+		while (context.i < length) {
+			const char = msg[context.i];
+			if (
+				char === this.opts.OPEN ||
 				char === this.opts.CLOSE ||
 				(!include_separator && char === this.opts.SEP) ||
 				(!include_space && SPACE.test(char)) ||
-				(special_hash && char === this.opts.SUB_VAR) )
-			break;
-
-		if ( char === this.opts.ESCAPE ) {
-			let next = msg[++context.i];
-			if ( next === this.opts.ESCAPE ) {
-				// Escaped Escape Character
-				out += next;
+				(special_hash && char === this.opts.SUB_VAR)
+			)
+				break;
+
+			if (char === this.opts.ESCAPE) {
+				let next = msg[++context.i];
+				if (next === this.opts.ESCAPE) {
+					// Escaped Escape Character
+					out += next;
+					context.i++;
+				} else if (
+					next === this.opts.OPEN ||
+					next === this.opts.CLOSE ||
+					(special_hash && next === this.opts.SUB_VAR) ||
+					!include_space ||
+					!include_separator
+				) {
+					// Special Character
+					out += next;
+
+					while (++context.i < length) {
+						next = msg[context.i];
+						if (next === this.opts.ESCAPE) {
+							// Check for an escaped escape character, and don't
+							// stop if we encounter one.
+							next = msg[context.i + 1];
+							if (next === this.opts.ESCAPE) {
+								out += next;
+								context.i++;
+							} else {
+								context.i++;
+								break;
+							}
+						} else out += next;
+					}
+				} else out += char;
+			} else {
 				context.i++;
-			} else if ( next === this.opts.OPEN || next === this.opts.CLOSE || (special_hash && next === this.opts.SUB_VAR) || ! include_space || ! include_separator ) {
-				// Special Character
-				out += next;
-				while( ++context.i < length ) {
-					next = msg[context.i];
-					if ( next === this.opts.ESCAPE ) {
-						// Check for an escaped escape character, and don't
-						// stop if we encounter one.
-						next = msg[context.i + 1];
-						if ( next === this.opts.ESCAPE ) {
-							out += next;
-							context.i++;
-						} else {
-							context.i++;
-							break;
-						}
-					} else
-						out += next;
-				}
-			} else
 				out += char;
+			}
+		}
 
-		} else {
+		return out;
+	}
+	
+	parseElement(context, parent) {
+		const msg = context.msg,
+			special_hash =
+				parent && this.opts.subnumeric_types.includes(parent.t);
+
+		let char = msg[context.i];
+		if (special_hash && char === this.opts.SUB_VAR) {
 			context.i++;
-			out += char;
+			return { v: parent.v };
 		}
-	}
 
-	return out;
-}
+		if (char !== this.opts.OPEN)
+			throw expected(this.opts.OPEN, char, context.i);
 
-Parser.prototype.parseElement = function(context, parent) {
-	const msg = context.msg,
-		special_hash = parent && this.opts.subnumeric_types.includes(parent.t);
+		context.i++;
+		skipSpace(context);
 
-	let char = msg[context.i];
+		// ID
+		const id = this.parseText(context, null, false, false);
+		if (!id) throw expected('placeholder id', char, context.i);
 
-	if ( special_hash && char === this.opts.SUB_VAR ) {
-		context.i++;
-		return {v: parent.v}
-	}
+		const out = { v: id };
+		skipSpace(context);
+		char = msg[context.i];
+
+		if (char === this.opts.CLOSE) {
+			context.i++;
+			return out;
+		} else if (char !== this.opts.SEP)
+			throw expected(
+				`${this.opts.SEP} or ${this.opts.CLOSE}`,
+				char,
+				context.i
+			);
 
-	if ( char !== this.opts.OPEN )
-		throw expected(this.opts.OPEN, char, context.i);
+		context.i++;
+		skipSpace(context);
 
-	context.i++;
-	skipSpace(context);
+		// Type
+		const type = this.parseText(context, null, false, false);
+		if (!type) throw expected('type', context);
 
-	// ID
-	const id = this.parseText(context, null, false, false);
-	if ( ! id )
-		throw expected('placeholder id', char, context.i);
+		out.t = type;
+		skipSpace(context);
+		char = msg[context.i];
 
-	const out = {v: id};
+		if (char === this.opts.CLOSE) {
+			if (this.opts.submessage_types.includes(out.t))
+				throw expected('sub-messages', context);
 
-	skipSpace(context);
+			context.i++;
+			return out;
+		} else if (char !== this.opts.SEP)
+			throw expected(
+				`${this.opts.SEP} or ${this.opts.CLOSE}`,
+				char,
+				context.i
+			);
 
-	char = msg[context.i];
-	if ( char === this.opts.CLOSE ) {
 		context.i++;
-		return out;
+		skipSpace(context);
 
-	} else if ( char !== this.opts.SEP )
-		throw expected(`${this.opts.SEP} or ${this.opts.CLOSE}`, char, context.i);
+		// Formatting
+		if (this.opts.subnumeric_types.includes(out.t)) {
+			const offset = this.parseOffset(context);
+			if (offset) {
+				out.f = offset;
+				skipSpace(context);
+			}
+		}
 
-	context.i++;
-	skipSpace(context);
+		if (this.opts.submessage_types.includes(out.t)) {
+			const submessages = this.parseSubmessages(context, out);
+			if (!submessages.other)
+				throw expected('other sub-message', context);
 
-	// Type
-	const type = this.parseText(context, null, false, false);
-	if ( ! type )
-		throw expected('type', context);
+			out.o = submessages;
+		} else {
+			const format = this.parseText(context, null, true, true);
+			if (!format) throw expected('format', context);
 
-	out.t = type;
-	skipSpace(context);
+			// Since we allow spaces mid-format, we should trim any
+			// remaining spaces off the end.
+			out.f = format.trimRight();
+		}
 
-	char = msg[context.i];
-	if ( char === this.opts.CLOSE ) {
-		if ( this.opts.submessage_types.includes(out.t) )
-			throw expected('sub-messages', context);
+		skipSpace(context);
+		char = msg[context.i];
+		if (char !== this.opts.CLOSE)
+			throw expected(this.opts.CLOSE, char, context.i);
 
 		context.i++;
 		return out;
+	}
+	
+	parseSubmessages(context, parent) {
+		const msg = context.msg,
+			length = msg.length,
+			out = {};
 
-	} else if ( char !== this.opts.SEP )
-		throw expected(`${this.opts.SEP} or ${this.opts.CLOSE}`, char, context.i);
+		while (context.i < length) {
+			const char = msg[context.i];
+			if (char === this.opts.CLOSE) break;
 
-	context.i++;
-	skipSpace(context);
+			const selector = this.parseText(context, null, true, false);
+			if (!selector) throw expected('sub-message selector', context);
 
-	// Formatting
-	if ( this.opts.subnumeric_types.includes(out.t) ) {
-		const offset = this.parseOffset(context);
-		if ( offset ) {
-			out.f = offset;
+			skipSpace(context);
+			out[selector] = this.parseSubmessage(context, parent);
 			skipSpace(context);
 		}
-	}
-
-	if ( this.opts.submessage_types.includes(out.t) ) {
-		const submessages = this.parseSubmessages(context, out);
-		if ( ! submessages.other )
-			throw expected('other sub-message', context);
-
-		out.o = submessages;
 
-	} else {
-		const format = this.parseText(context, null, true, true);
-		if ( ! format )
-			throw expected('format', context);
-
-		// Since we allow spaces mid-format, we should trim any
-		// remaining spaces off the end.
-		out.f = format.trimRight();
+		return out;
 	}
+	
+	parseSubmessage(context, parent) {
+		const msg = context.msg;
 
-	skipSpace(context);
-	char = msg[context.i];
-	if ( char !== this.opts.CLOSE )
-		throw expected(this.opts.CLOSE, char, context.i);
+		if (msg[context.i] !== this.opts.OPEN)
+			throw expected(this.opts.OPEN, context);
 
-	context.i++;
-	return out;
-}
-
-
-Parser.prototype.parseSubmessages = function(context, parent) {
-	const msg = context.msg,
-		length = msg.length,
-		out = {};
-
-	while(context.i < length ) {
-		const char = msg[context.i];
-		if ( char === this.opts.CLOSE )
-			break;
+		context.i++;
+		const out = this.parseAST(context, parent);
 
-		const selector = this.parseText(context, null, true, false);
-		if ( ! selector )
-			throw expected('sub-message selector', context);
+		if (msg[context.i] !== this.opts.CLOSE)
+			throw expected(this.opts.CLOSE, context);
 
-		skipSpace(context);
-		out[selector] = this.parseSubmessage(context, parent);
-		skipSpace(context);
+		context.i++;
+		return out;
 	}
+	
+	parseOffset(context) {
+		const msg = context.msg,
+			OFFSET = this.opts.OFFSET,
+			length = msg.length;
 
-	return out;
-}
-
-
-Parser.prototype.parseSubmessage = function(context, parent) {
-	const msg = context.msg;
-
-	if ( msg[context.i] !== this.opts.OPEN )
-		throw expected(this.opts.OPEN, context);
-
-	context.i++;
-	const out = this.parseAST(context, parent);
+		if (msg.slice(context.i, context.i + OFFSET.length) !== OFFSET) return;
 
-	if ( msg[context.i] !== this.opts.CLOSE )
-		throw expected(this.opts.CLOSE, context);
-
-	context.i++;
-	return out;
-}
-
-
-Parser.prototype.parseOffset = function(context) {
-	const msg = context.msg,
-		OFFSET = this.opts.OFFSET,
-		length = msg.length;
-
-	if ( msg.slice(context.i, context.i + OFFSET.length) !== OFFSET )
-		return;
-
-	context.i += OFFSET.length;
-	skipSpace(context);
+		context.i += OFFSET.length;
+		skipSpace(context);
 
-	const start = context.i;
-	while(context.i < length && /\d/.test(msg[context.i]))
-		context.i++;
+		const start = context.i;
+		while (context.i < length && /\d/.test(msg[context.i])) context.i++;
 
-	if ( start === context.i )
-		throw expected('number', context);
+		if (start === context.i) throw expected('number', context);
 
-	return +msg.slice(start, context.i);
+		return +msg.slice(start, context.i);
+	}
 }
 
-
 function expected(char, found, index) {
-	if ( typeof found === 'object' ) {
+	if (typeof found === 'object') {
 		index = found.i;
 		found = found.msg[index];
 	}
 
-	return new SyntaxError(`expected ${char} at position ${index} but found ${found || 'eof'}`);
+	return new SyntaxError(
+		`expected ${char} at position ${index} but found ${found || 'eof'}`
+	);
 }
 
 function unexpected(char, index) {
-	return new SyntaxError(`unexpected ${char} at position ${index}`)
+	return new SyntaxError(`unexpected ${char} at position ${index}`);
 }
 
 function skipSpace(context) {
 	const msg = context.msg,
 		length = msg.length;
 
-	while ( context.i < length && SPACE.test(msg[context.i]) )
-		context.i++;
+	while (context.i < length && SPACE.test(msg[context.i])) context.i++;
 }
+
+exports = module.exports = new Proxy(Parser, {
+	apply: (target, _, argumentsList) =>
+		Reflect.construct(target, argumentsList)
+});