Add dynamic-import test

packages/dependency-extraction-webpack-plugin/test/__snapshots__/build.js.snap

@@ -1,5 +1,34 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`Webpack \`dynamic-import\` should produce expected output: Dependencies JSON should match snapshot 1`] = `
+Array [
+  "lodash",
+  "wp-blob",
+]
+`;
+
+exports[`Webpack \`dynamic-import\` should produce expected output: External modules should match snapshot 1`] = `
+Array [
+  Object {
+    "externalType": "this",
+    "request": Object {
+      "this": Array [
+        "wp",
+        "blob",
+      ],
+    },
+    "userRequest": "@wordpress/blob",
+  },
+  Object {
+    "externalType": "this",
+    "request": Object {
+      "this": "lodash",
+    },
+    "userRequest": "lodash",
+  },
+]
+`;
+
 exports[`Webpack \`no-default\` should produce expected output: Dependencies JSON should match snapshot 1`] = `Array []`;
 
 exports[`Webpack \`no-default\` should produce expected output: External modules should match snapshot 1`] = `Array []`;

packages/dependency-extraction-webpack-plugin/test/fixtures/dynamic-import/index.js

@@ -0,0 +1,6 @@
+/**
+ * External dependencies
+ */
+import _ from 'lodash';
+
+import( './util' ).then( _.noop );

packages/dependency-extraction-webpack-plugin/test/fixtures/dynamic-import/util.js

@@ -0,0 +1,6 @@
+/**
+ * WordPress dependencies
+ */
+import { isBlobURL } from '@wordpress/blob';
+
+isBlobURL();

packages/dependency-extraction-webpack-plugin/test/fixtures/dynamic-import/webpack.config.js

@@ -0,0 +1,5 @@
+const DependencyExtractionWebpackPlugin = require( '../../..' );
+
+module.exports = {
+	plugins: [ new DependencyExtractionWebpackPlugin() ],
+};