First list and integer questions, spaces to tabs

src/normalizers.js

@@ -2,31 +2,48 @@ import fs from 'fs';
 import path from 'path';
 
 export function boolean(value) {
-    if (typeof value === 'boolean') {
-        return value;
-    } else if (value === 'true') {
-        return true;
-    } else if (value === 'false') {
-        return false;
-    }
+	if (typeof value === 'boolean') {
+		return value;
+	} else if (value === 'true') {
+		return true;
+	} else if (value === 'false') {
+		return false;
+	}
 
-    throw new Error('Must be true or false.');
+	throw new Error('Must be true or false.');
 }
 
 export function filePath(value) {
-    const unwrapped = value.replace(/"(.*?)"/, '$1');
-    const absolute = path.resolve(unwrapped);
+	const unwrapped = value.replace(/"(.*?)"/, '$1');
+	const absolute = path.resolve(unwrapped);
 
-    let fileExists;
-    try {
-        fileExists = fs.existsSync(absolute) && fs.statSync(absolute).isFile();
-    } catch (ex) {
-        fileExists = false;
-    }
+	let fileExists;
+	try {
+		fileExists = fs.existsSync(absolute) && fs.statSync(absolute).isFile();
+	} catch (ex) {
+		fileExists = false;
+	}
 
-    if (fileExists) {
-        return absolute;
-    } else {
-        throw new Error('File not found at ' + absolute + '.');
-    }
+	if (fileExists) {
+		return absolute;
+	}
+
+	throw new Error('File not found at ' + absolute + '.');
+}
+
+export function list(value) {
+	if (Array.isArray(value)) {
+		return value;
+	} else {
+		return value.trim().split(/\s*,\s*/);
+	}
+}
+
+export function integer(value) {
+	const int = parseInt(value);
+	if (!Number.isNaN(int) && int >= 0) {
+		return int;
+	}
+
+	throw new Error('Must be an integer >= 0.');
 }