Change the index file format to use "export ... from" (fixes #3)

src/utilities/readDirectory.js

@@ -0,0 +1,97 @@
+import fs from 'fs';
+import _ from 'lodash';
+import path from 'path';
+import validateTargetDirectory from './validateTargetDirectory';
+
+let hasIndex,
+    hasMultipleExtensions,
+    hasNoExtension,
+    isSafeName,
+    removeDuplicates;
+
+hasIndex = (directoryPath) => {
+    let indexPath;
+
+    indexPath = path.resolve(directoryPath, 'index.js');
+
+    try {
+        fs.statSync(indexPath);
+
+        return true;
+    } catch (error) {
+        return false;
+    }
+};
+
+hasNoExtension = (fileName) => {
+    let matches;
+
+    matches = fileName.match(/\./g);
+
+    return !matches;
+};
+
+hasMultipleExtensions = (fileName) => {
+    let matches;
+
+    matches = fileName.match(/\./g);
+
+    return matches && matches.length > 1;
+};
+
+isSafeName = (fileName) => {
+    return /^[a-z][a-z0-9\.]+$/i.test(fileName);
+};
+
+removeDuplicates = (files) => {
+    return _.filter(files, (fileName) => {
+        return !_.includes(files, fileName + '.js');
+    });
+};
+
+export default (directoryPath) => {
+    let children;
+
+    validateTargetDirectory(directoryPath);
+
+    children = fs.readdirSync(directoryPath);
+
+    children = _.filter(children, (fileName) => {
+        let absolutePath,
+            isDirectory;
+
+        absolutePath = path.resolve(directoryPath, fileName);
+
+        isDirectory = fs.statSync(absolutePath).isDirectory();
+
+        if (!isSafeName(fileName)) {
+            return false;
+        }
+
+        if (hasNoExtension(fileName) && !isDirectory) {
+            return false;
+        }
+
+        if (hasMultipleExtensions(fileName)) {
+            return false;
+        }
+
+        if (_.startsWith(fileName, 'index.js')) {
+            return false;
+        }
+
+        if (!isDirectory && !_.endsWith(fileName, '.js')) {
+            return false;
+        }
+
+        if (isDirectory && !hasIndex(absolutePath)) {
+            return false;
+        }
+
+        return true;
+    });
+
+    children = removeDuplicates(children);
+
+    return children.sort();
+};