[BUGFIX release] Require Octane features when using Octane preview.

lib/index.js

@@ -63,6 +63,55 @@ module.exports = {
   paths,
   absolutePaths,
 
+  included() {
+    this._super.included.apply(this, arguments);
+
+    const { has } = require('@ember/edition-utils');
+
+    if (has('octane')) {
+      let optionalFeatures = this.project.addons.find(a => a.name === '@ember/optional-features');
+      let optionalFeaturesMissing = optionalFeatures !== undefined;
+      let missingFeatures = [];
+
+      if (optionalFeaturesMissing) {
+        missingFeatures.push(
+          `* the @ember/optional-features addon is missing, run \`ember install @ember/optional-features\` to install it`
+        );
+      }
+
+      if (optionalFeaturesMissing || optionalFeatures.isFeatureEnabled('jquery-integration')) {
+        missingFeatures.push(
+          `* The jquery-integration optional feature should be disabled under Octane, run \`ember feature:disable jquery-integration\` to disable it`
+        );
+      }
+
+      if (
+        optionalFeaturesMissing ||
+        optionalFeatures.isFeatureEnabled('application-template-wrapper')
+      ) {
+        missingFeatures.push(
+          `* The application-template-wrapper optional feature should be disabled under Octane, run \`ember feature:disable application-template-wrapper\` to disable it`
+        );
+      }
+
+      if (
+        optionalFeaturesMissing ||
+        !optionalFeatures.isFeatureEnabled('template-only-glimmer-component')
+      ) {
+        missingFeatures.push(
+          `* The template-only-glimmer-component optional feature should be enabled under Octane, run \`ember feature:enabled template-only-glimmer-component\` to enable it`
+        );
+      }
+
+      if (missingFeatures.length > 0) {
+        let intro = `You have configured your application to indicate that it is using the 'octane' edition (via \`setEdition('octane')\`), but the appropriate Octane features were not enabled:`;
+
+        const SilentError = require('silent-error');
+        throw new SilentError(`${intro}\n\n${missingFeatures.join('\n\t')}`);
+      }
+    }
+  },
+
   transpileTree(tree, isProduction) {
     let emberCliBabel = this.addons.find(a => a.name === 'ember-cli-babel');