SIP-32: Moving frontend code to the base of the repo (#9098)

* move assets out, get webpack dev working

* update docs to reference superset-frontend

* draw the rest of the owl

* fix docs

* fix webpack script

* rats

* correct docs

* fix tox dox

superset-frontend/spec/javascripts/utils/getClientErrorObject_spec.js

@@ -0,0 +1,61 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+import getClientErrorObject from '../../../src/utils/getClientErrorObject';
+
+describe('getClientErrorObject()', () => {
+  it('Returns a Promise', () => {
+    const response = getClientErrorObject('error');
+    expect(response.constructor === Promise).toBe(true);
+  });
+
+  it('Returns a Promise that resolves to an object with an error key', () => {
+    const error = 'error';
+
+    return getClientErrorObject(error).then(errorObj => {
+      expect(errorObj).toMatchObject({ error });
+    });
+  });
+
+  it('Handles Response that can be parsed as json', () => {
+    const jsonError = { something: 'something', error: 'Error message' };
+    const jsonErrorString = JSON.stringify(jsonError);
+
+    return getClientErrorObject(new Response(jsonErrorString)).then(
+      errorObj => {
+        expect(errorObj).toMatchObject(jsonError);
+      },
+    );
+  });
+
+  it('Handles Response that can be parsed as text', () => {
+    const textError = 'Hello I am a text error';
+
+    return getClientErrorObject(new Response(textError)).then(errorObj => {
+      expect(errorObj).toMatchObject({ error: textError });
+    });
+  });
+
+  it('Handles plain text as input', () => {
+    const error = 'error';
+
+    return getClientErrorObject(error).then(errorObj => {
+      expect(errorObj).toMatchObject({ error });
+    });
+  });
+});