haskell support (thanks @RaphyJake), cleaner readline for JS, size tool

.gitignore

@@ -1,2 +1,3 @@
 node_modules
 package-lock.json
+testing

index.js

@@ -9,7 +9,10 @@ const run = require('./runner');
 const { fatal, failed } = require('./errors');
 
 const args = parseArgs(process.argv.slice(2), {
-	alias: { t: 'test' }
+	alias: {
+		t: 'test',
+		s: 'size'
+	}
 });
 
 const readTests = () => {
@@ -49,4 +52,16 @@ const main = tests => {
 	}
 };
 
+if (args.size) {
+	const files = Array.isArray(args.size)
+		? args.size
+		: [ args.size ];
+	// eslint-disable-next-line global-require
+	const { statSync } = require('fs');
+	files.forEach(file =>
+		console.log(
+			file + ': ' +
+			statSync(file).size + ' bytes'));
+}
+
 readTests().then(main);

readline/child.js

@@ -1,10 +0,0 @@
-'use strict';
-
-const { createInterface } = require('readline');
-
-const rl = createInterface({ input: process.stdin });
-
-rl.once('line', line => {
-	process.stdout.write(line);
-	process.stdin.pause();
-});

readline/index.js

@@ -1,14 +1,21 @@
 'use strict';
 
-const { join } = require('path');
-const { spawnSync } = require('child_process');
+const { readSync } = require('fs');
 
 const readline = () => {
-	const { stdout } = spawnSync(
-		'node',
-		[ join(__dirname, 'child.js') ],
-		{ stdio: [ 'inherit', 'pipe', 'ignore' ] });
-	return String(stdout);
+	let line = '';
+	let char = '';
+	const buf = Buffer.alloc(1);
+	while (char !== '\r' && char !== '\n') {
+		line += char;
+		try {
+			readSync(process.stdin.fd, buf, 0, 1);
+		} catch (err) {
+			return line;
+		}
+		char = String(buf);
+	}
+	return line;
 };
 
 module.exports = readline;

runner/index.js

@@ -29,15 +29,8 @@ const runners = {
 				: [],
 			'-r', join(__dirname, 'setup.js'), path
 		], input),
-	hs: (path, input) => {
-		const [ cout, cerr, code ] = spawn(
-			'ghc',
-			[ path ]);
-		if (code > 0) {
-			return [ cout, cerr ];
-		}
-		return spawn(basename(path, '.hs'), [], input);
-	}
+	hs: (path, input) =>
+		spawn('runhaskell', [ path ], input)
 };
 
 const run = (path, input = null) => {