Lint: Add miscellaneous extra rules

Among the newly added rules, there are quite a few intended to enforce
compliance of CONTRIBUTING.md-blessed idioms, as well as ensure
safe usage of classes and constant bindings.

We are also now enforcing usage of early return in commands.js,
which has 100% compliance as of fd2c45c.

.eslintrc

@@ -19,20 +19,20 @@
 		"comma-dangle": [2, "always-multiline"],
 		"no-cond-assign": [2, "except-parens"],
 		"no-console": 0,
-		"no-constant-condition": 0,
+		"no-constant-condition": 2,
 		"no-control-regex": 0,
 		"no-debugger": 2,
 		"no-dupe-args": 2,
 		"no-dupe-keys": 2,
 		"no-duplicate-case": 2,
 		"no-empty-character-class": 2,
-		"no-empty": 0,
+		"no-empty": [2, {"allowEmptyCatch": true}],
 		"no-ex-assign": 2,
-		"disallow-extra-boolean-casts": 0,
+		"no-extra-boolean-cast": 2,
 		"no-extra-parens": 0,
 		"no-extra-semi": 2,
 		"no-func-assign": 2,
-		"no-inner-declarations": 2,
+		"no-inner-declarations": [2, "functions"],
 		"no-invalid-regexp": 2,
 		"no-irregular-whitespace": 2,
 		"no-negated-in-lhs": 2,
@@ -45,6 +45,7 @@
 		"valid-jsdoc": 0,
 		"valid-typeof": 2,
 
+		"array-callback-return": 2,
 		"block-scoped-var": 2,
 		"complexity": 0,
 		"consistent-return": 0,
@@ -53,6 +54,7 @@
 		"dot-location": [2, "property"],
 		"dot-notation": 0,
 		"eqeqeq": 2,
+		"guard-for-in": 0,
 		"no-caller": 2,
 		"no-case-declarations": 0,
 		"no-div-regex": 2,
@@ -63,30 +65,34 @@
 		"no-implied-eval": 2,
 		"no-extend-native": 2,
 		"no-extra-bind": 1,
+		"no-extra-label": 2,
 		"no-fallthrough": 2,
 		"no-floating-decimal": 2,
 		"no-implicit-coercion": 0,
 		"no-invalid-this": 0,
+		"no-iterator": 2,
 		"no-lone-blocks": 0,
 		"no-loop-func": 0,
 		"no-magic-numbers": 0,
-		"no-multi-spaces": 0,
+		"no-multi-spaces": 1,
 		"no-multi-str": 2,
 		"no-native-reassign": 2,
 		"no-new-func": 2,
 		"no-new-wrappers": 2,
 		"no-new": 2,
 		"no-octal-escape": 2,
-		"no-octal": 1,
+		"no-octal": 2,
 		"no-param-reassign": 0,
-		"no-process-env": 0,
 		"no-proto": 2,
 		"no-redeclare": 2,
 		"no-return-assign": [2, "except-parens"],
+		"no-self-assign": 2,
 		"no-self-compare": 2,
-		"no-sequences": 1,
+		"no-sequences": 2,
 		"no-throw-literal": 2,
+		"no-unmodified-loop-condition": 2,
 		"no-unused-expressions": 2,
+		"no-unused-labels": 2,
 		"no-useless-call": 2,
 		"no-useless-concat": 0,
 		"no-void": 0,
@@ -96,23 +102,32 @@
 		"vars-on-top": 0,
 		"wrap-iife": [2, "inside"],
 		"yoda": 0,
+
 		"strict": [2, "global"],
+
 		"init-declarations": 0,
+		"no-catch-shadow": 0,
 		"no-delete-var": 2,
 		"no-label-var": 2,
+		"no-restricted-globals": [2, "Proxy", "Reflect", "Symbol", "WeakSet"],
 		"no-shadow-restricted-names": 2,
 		"no-shadow": 0,
-		"no-undef-init": 0,
+		"no-undef-init": 1,
 		"no-undef": [2, {"typeof": true}],
 		"no-undefined": 0,
 		"no-unused-vars": [1, {"args": "none"}],
-		"no-use-before-define": [2, "nofunc"],
+		"no-use-before-define": [2, {"functions": false, "classes": false}],
 
+		"callback-return": [2, ["callback", "cb", "done"]],
+		"no-mixed-requires": 2,
 		"no-new-require": 2,
+		"no-path-concat": 0,
+		"no-process-env": 0,
+		"no-process-exit": 0,
+		"no-restricted-modules": [2, "moment", "request", "sugar"],
+		"no-sync": 0,
 
 		"array-bracket-spacing": [2, "never"],
-		"arrow-parens": [2, "as-needed"],
-		"arrow-spacing": [2, {"before": true, "after": true}],
 		"block-spacing": 0,
 		"brace-style": [2, "1tbs", {"allowSingleLine": true}],
 		"camelcase": 0,
@@ -128,9 +143,11 @@
 		"key-spacing": 0,
 		"lines-around-comment": 0,
 		"max-nested-callbacks": 0,
+		"max-statements-per-line": 0,
 		"new-cap": [2, {"newIsCap": true, "capIsNew": false}],
 		"new-parens": 2,
 		"newline-after-var": 0,
+		"newline-before-return": 0,
 		"no-array-constructor": 2,
 		"no-continue": 0,
 		"no-inline-comments": 0,
@@ -145,7 +162,6 @@
 		"no-trailing-spaces": 2,
 		"no-underscore-dangle": 0,
 		"no-unneeded-ternary": 2,
-		"no-var": 2,
 		"object-curly-spacing": [2, "never"],
 		"one-var": 0,
 		"operator-assignment": 0,
@@ -166,6 +182,19 @@
 		"spaced-comment": 0,
 		"wrap-regex": 0,
 
+		"arrow-parens": [2, "as-needed"],
+		"arrow-spacing": [2, {"before": true, "after": true}],
+		"constructor-super": 2,
+		"no-class-assign": 2,
+		"no-confusing-arrow": 0,
+		"no-const-assign": 2,
+		"no-dupe-class-members": 2,
+		"no-this-before-super": 2,
+		"no-var": 2,
+		"require-yield": 2,
+		"template-curly-spacing": [2, "never"],
+		"no-restricted-syntax": [2, "TaggedTemplateExpression", "ObjectPattern", "ArrayPattern"],
+
 		"validate-conditionals": 2,
 	}
 }

chat-plugins/datasearch.js

@@ -625,7 +625,7 @@ function runDexsearch(target, cmd, canAll, message) {
 				for (let i = 0; i < moveGroups[group].length; i++) {
 					let problem = TeamValidator('anythinggoes').checkLearnset(moveGroups[group][i], mon, lsetData);
 					if (!problem) break;
-					if (i === moveGroups[group].length - 1) return;
+					if (i === moveGroups[group].length - 1) return false;
 				}
 			}
 			return true;

chat-plugins/jeopardy.js

@@ -133,7 +133,7 @@ let Jeopardy = (() => {
 		let checks = Array.prototype.slice.call(arguments, 2);
 
 		let currentCheck = '';
-		while (!!(currentCheck = checks.pop())) {
+		while ((currentCheck = checks.pop())) {
 			switch (currentCheck) {
 			case 'started':
 				if (this.isStarted) break;

chat-plugins/mafia.js

@@ -619,7 +619,7 @@ class Mafia extends Rooms.RoomGame {
 			this.timer = setTimeout(() => {
 				this.progress();
 			}, 10000);
-		}, ((mins -  0.167) * 60000));
+		}, ((mins - 0.167) * 60000));
 	}
 
 	// Meetings:

chat-plugins/tcgtabletop.js

@@ -31,8 +31,8 @@ function wikiaSearch(subdomain, query, callback) {
 			return callback(null, result.items[0]);
 		});
 	}).once('error', function (err) {
-		callback(err);
 		this.on('error', noop);
+		callback(err);
 	});
 }
 

commands.js

@@ -15,6 +15,8 @@
 
 'use strict';
 
+/* eslint no-else-return: "error" */
+
 const crypto = require('crypto');
 const fs = require('fs');
 
@@ -378,7 +380,6 @@ exports.commands = {
 		if (Rooms.search(roomid)) return this.errorReply("A group chat named '" + title + "' already exists.");
 		// Tab title is prefixed with '[G]' to distinguish groupchats from
 		// registered chatrooms
-		title = title;
 
 		if (Monitor.countGroupChat(connection.ip)) {
 			this.errorReply("Due to high load, you are limited to creating 4 group chats every hour.");

data/scripts.js

@@ -760,10 +760,15 @@ exports.BattleScripts = {
 			}
 
 			// Make sure forme/item combo is correct
-			while ((poke === 'Giratina' && item === 'griseousorb') ||
-					(poke === 'Arceus' && item.substr(-5) === 'plate') ||
-					(poke === 'Genesect' && item.substr(-5) === 'drive')) {
-				item = items[this.random(items.length)];
+			switch (poke) {
+			case 'Giratina':
+				while (item === 'griseousorb') item = items[this.random(items.length)];
+				break;
+			case 'Arceus':
+				while (item.substr(-5) === 'plate') item = items[this.random(items.length)];
+				break;
+			case 'Genesect':
+				while (item.substr(-5) === 'drive') item = items[this.random(items.length)];
 			}
 
 			// Random ability
@@ -917,12 +922,12 @@ exports.BattleScripts = {
 
 			// Random unique moves
 			let m = [];
-			while (true) {
+			do {
 				let moveid = this.sampleNoReplace(movePool);
 				if (!this.data.Movedex[moveid].isNonstandard && (moveid === 'hiddenpower' || moveid.substr(0, 11) !== 'hiddenpower')) {
-					if (m.push(moveid) >= 4) break;
+					m.push(moveid);
 				}
-			}
+			} while (m.length < 4);
 
 			// Random EVs
 			let evs = {hp: 0, atk: 0, def: 0, spa: 0, spd: 0, spe: 0};
@@ -1311,7 +1316,7 @@ exports.BattleScripts = {
 					if (counter.setupType || !!counter['speedsetup'] || (hasMove['rest'] && hasMove['sleeptalk'])) rejected = true;
 					break;
 				case 'healbell':
-					if (!!counter['speedsetup']) rejected = true;
+					if (counter['speedsetup']) rejected = true;
 					break;
 				case 'healingwish': case 'memento':
 					if (counter.setupType || !!counter['recovery'] || hasMove['substitute']) rejected = true;

dnsbl.js

@@ -35,11 +35,10 @@ function queryDnsblLoop(ip, callback, reversedIpDot, index) {
 		if (!err) {
 			// blocked
 			dnsblCache.set(ip, blocklist);
-			callback(blocklist);
-		} else {
-			// not blocked, try next blocklist
-			queryDnsblLoop(ip, callback, reversedIpDot, index + 1);
+			return callback(blocklist);
 		}
+		// not blocked, try next blocklist
+		queryDnsblLoop(ip, callback, reversedIpDot, index + 1);
 	});
 }
 

mods/gen5/moves.js

@@ -133,6 +133,7 @@ exports.BattleMovedex = {
 				if (move.id !== 'conversion' && !target.hasType(move.type)) {
 					return move.type;
 				}
+				return '';
 			}).filter(type => type);
 			if (!possibleTypes.length) {
 				return false;

mods/seasonal/scripts.js

@@ -387,7 +387,7 @@ exports.BattleScripts = {
 				species: 'Mr. Mime', ability: 'Prankster', item: 'Leftovers', gender: 'M',
 				moves: ['batonpass', ['substitute', 'milkdrink'][this.random(2)], 'encore'],
 				signatureMove: "Meme Mime",
-				evs: {hp:252, def:4, spe:252},  ivs: {atk:0, spa:0}, nature: 'Timid',
+				evs: {hp:252, def:4, spe:252}, ivs: {atk:0, spa:0}, nature: 'Timid',
 			},
 			'ih8ih8sn0w': {
 				species: 'Deoxys-Speed', ability: 'Pressure', item: 'Leftovers', gender: 'N', shiny: true,

repl.js

@@ -61,9 +61,9 @@ exports.start = function (prefix, suffix, evalFunction) {
 			output: socket,
 			eval: (cmd, context, filename, callback) => {
 				try {
-					callback(null, evalFunction(cmd));
+					return callback(null, evalFunction(cmd));
 				} catch (e) {
-					callback(e);
+					return callback(e);
 				}
 			},
 		}).on('exit', () => socket.end());

test/simulator/items/shedshell.js

@@ -13,7 +13,7 @@ describe('Shed Shell', function () {
 		battle.join('p1', 'Guest 1', 1, [{species: "Gothitelle", ability: 'shadowtag', moves: ['calmmind']}]);
 		battle.join('p2', 'Guest 2', 1, [
 			{species: "Starmie", ability: 'naturalcure', item: 'shedshell', moves: ['recover']},
-			{species: "Heatran", ability: 'flashfire',  moves: ['rest']},
+			{species: "Heatran", ability: 'flashfire', moves: ['rest']},
 		]);
 		battle.choose('p2', 'switch 2');
 		battle.commitDecisions();
@@ -25,7 +25,7 @@ describe('Shed Shell', function () {
 		battle.join('p1', 'Guest 1', 1, [{species: "Gengar", ability: 'levitate', moves: ['meanlook']}]);
 		battle.join('p2', 'Guest 2', 1, [
 			{species: "Venusaur", ability: 'overgrow', item: 'shedshell', moves: ['ingrain']},
-			{species: "Heatran", ability: 'flashfire',  moves: ['rest']},
+			{species: "Heatran", ability: 'flashfire', moves: ['rest']},
 		]);
 		battle.commitDecisions();
 		battle.choose('p2', 'switch 2');
@@ -38,7 +38,7 @@ describe('Shed Shell', function () {
 		battle.join('p1', 'Guest 1', 1, [{species: "Dragonite", ability: 'multiscale', moves: ['skydrop']}]);
 		battle.join('p2', 'Guest 2', 1, [
 			{species: "Magnezone", ability: 'sturdy', item: 'shedshell', moves: ['sleeptalk']},
-			{species: "Heatran", ability: 'flashfire',  moves: ['rest']},
+			{species: "Heatran", ability: 'flashfire', moves: ['rest']},
 		]);
 		battle.commitDecisions();
 		battle.choose('p2', 'switch 2');

test/simulator/misc/eventemitter.js

@@ -37,14 +37,14 @@ describe('Battle#on', function () {
 		battle.join('p2', 'Guest 2', 1, [{species: 'Talonflame', ability: 'galewings', moves: ['peck']}]);
 		battle.commitDecisions(); // Team Preview
 		let eventCount = 0;
-		let callback = function (count) {
+		let modHandler = function (count) {
 			return function () {
 				assert.strictEqual(eventCount, count);
 				eventCount++;
 			};
 		};
 		for (let i = 0; i < 9; i++) {
-			battle.on('ModifyDamage', battle.getFormat(), -i, callback(i));
+			battle.on('ModifyDamage', battle.getFormat(), -i, modHandler(i));
 		}
 		battle.commitDecisions();
 		assert.strictEqual(eventCount, 9);

tools.js

@@ -247,7 +247,7 @@ module.exports = (() => {
 			if (!this.data.Pokedex[id]) {
 				if (id.startsWith('mega') && this.data.Pokedex[id.slice(4) + 'mega']) {
 					id = id.slice(4) + 'mega';
-				} else if (id.startsWith('m') && this.data.Pokedex[id.slice(1) + 'mega'])  {
+				} else if (id.startsWith('m') && this.data.Pokedex[id.slice(1) + 'mega']) {
 					id = id.slice(1) + 'mega';
 				} else if (id.startsWith('primal') && this.data.Pokedex[id.slice(6) + 'primal']) {
 					id = id.slice(6) + 'primal';

users.js

@@ -59,9 +59,11 @@ function getUser(name, exactName) {
 	if (name && name.userid) return name;
 	let userid = toId(name);
 	let i = 0;
-	while (!exactName && userid && !users.has(userid) && i < 1000) {
-		userid = prevUsers.get(userid);
-		i++;
+	if (!exactName) {
+		while (userid && !users.has(userid) && i < 1000) {
+			userid = prevUsers.get(userid);
+			i++;
+		}
 	}
 	return users.get(userid);
 }
@@ -631,7 +633,7 @@ class User {
 
 		for (let i = 0; i < this.connections.length; i++) {
 			// console.log('' + name + ' renaming: connection ' + i + ' of ' + this.connections.length);
-			let initdata = '|updateuser|' + this.name + '|' + (false ? '1' : '0') + '|' + this.avatar;
+			let initdata = '|updateuser|' + this.name + '|' + ('0' /* not named */) + '|' + this.avatar;
 			this.connections[i].send(initdata);
 		}
 		this.named = false;
@@ -916,7 +918,7 @@ class User {
 
 		for (let i = 0; i < this.connections.length; i++) {
 			//console.log('' + name + ' renaming: socket ' + i + ' of ' + this.connections.length);
-			let initdata = '|updateuser|' + this.name + '|' + (true ? '1' : '0') + '|' + this.avatar;
+			let initdata = '|updateuser|' + this.name + '|' + ('1' /* named */) + '|' + this.avatar;
 			this.connections[i].send(initdata);
 		}
 		let joining = !this.named;
@@ -972,7 +974,7 @@ class User {
 		this.connected = true;
 		this.connections.push(connection);
 		//console.log('' + this.name + ' merging: connection ' + connection.socket.id);
-		let initdata = '|updateuser|' + this.name + '|' + (true ? '1' : '0') + '|' + this.avatar;
+		let initdata = '|updateuser|' + this.name + '|' + ('1' /* named */) + '|' + this.avatar;
 		connection.send(initdata);
 		connection.user = this;
 		for (let i in connection.rooms) {