fix: add safe traverse to loaderoptionsplugin (#77)

* fix: add safe traverse to loaderoptionsplugin

* test: write a failing test case

lib/transformations/loaderOptionsPlugin/__snapshots__/loaderOptionsPlugin.test.js.snap

@@ -37,3 +37,24 @@ module.exports = {
 }
 "
 `;
+
+exports[`loaderOptionsPlugin transforms correctly using "loaderOptionsPlugin-3" data 1`] = `
+"// Don't modify LoaderOptionsPlugin
+
+const ExtractTextPlugin = require('extract-text-webpack-plugin');
+module.exports = {
+    entry: ['./index.js'],
+    output: {
+        filename: 'bundle.js'
+    },
+    module: {
+		rules: [{
+			test: /\\\\.css$/,
+			use: ExtractTextPlugin.extract([
+				'css-loader'
+			])
+		}]
+	},
+}
+"
+`;

lib/transformations/loaderOptionsPlugin/__testfixtures__/loaderOptionsPlugin-3.input.js

@@ -0,0 +1,17 @@
+// Don't modify LoaderOptionsPlugin
+
+const ExtractTextPlugin = require('extract-text-webpack-plugin');
+module.exports = {
+    entry: ['./index.js'],
+    output: {
+        filename: 'bundle.js'
+    },
+    module: {
+		rules: [{
+			test: /\.css$/,
+			use: ExtractTextPlugin.extract([
+				'css-loader'
+			])
+		}]
+	},
+}

lib/transformations/loaderOptionsPlugin/loaderOptionsPlugin.js

@@ -1,6 +1,7 @@
 const isEmpty = require('lodash/isEmpty');
 const findPluginsByName = require('../utils').findPluginsByName;
 const createOrUpdatePluginByName = require('../utils').createOrUpdatePluginByName;
+const safeTraverse = require('../utils').safeTraverse;
 
 module.exports = function(j, ast) {
 	const loaderOptions = {};
@@ -19,7 +20,7 @@ module.exports = function(j, ast) {
 
 	return ast
 		.find(j.ArrayExpression)
-		.filter(path => path.parent.value.key.name === 'plugins')
+		.filter(path => safeTraverse(path, ['parent', 'value', 'key', 'name']) === 'plugins')
 		.forEach(path => {
 			!isEmpty(loaderOptions) &&
 			createOrUpdatePluginByName(j, path, 'webpack.optimize.LoaderOptionsPlugin', loaderOptions);

lib/transformations/loaderOptionsPlugin/loaderOptionsPlugin.test.js

@@ -3,3 +3,4 @@ const defineTest = require('../defineTest');
 defineTest(__dirname, 'loaderOptionsPlugin', 'loaderOptionsPlugin-0');
 defineTest(__dirname, 'loaderOptionsPlugin', 'loaderOptionsPlugin-1');
 defineTest(__dirname, 'loaderOptionsPlugin', 'loaderOptionsPlugin-2');
+defineTest(__dirname, 'loaderOptionsPlugin', 'loaderOptionsPlugin-3');