CodeEditor: Improved styles when the code editor is loading (#88102)

* fix: monaco loading state

* chore: betterer

* test: leverage e2e selectors

* refactor: prefer HOC to wrap with testid

* refactor: add clarity

* docs: add clarity

* refactor: loading messaging

* test: rename vars to improve clarity

* test: rename vars to improve clarity

.betterer.results

@@ -5054,8 +5054,6 @@ exports[`no gf-form usage`] = {
       [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"]
     ],
     "packages/grafana-prometheus/src/components/PromQueryField.tsx:5381": [
-      [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"],
-      [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"],
       [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"],
       [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"],
       [0, 0, 0, "gf-form usage has been deprecated. Use a component from @grafana/ui or custom CSS instead.", "5381"],

packages/grafana-e2e-selectors/src/selectors/components.ts

@@ -526,6 +526,9 @@ export const Components = {
   CodeEditor: {
     container: 'data-testid Code editor container',
   },
+  ReactMonacoEditor: {
+    container: 'data-testid ReactMonacoEditor container',
+  },
   DashboardImportPage: {
     textarea: 'data-testid-import-dashboard-textarea',
     submit: 'data-testid-load-dashboard',

packages/grafana-prometheus/src/components/PromQueryField.tsx

@@ -238,7 +238,7 @@ class PromQueryFieldClass extends React.PureComponent<PromQueryFieldProps, PromQ
                   <Icon name={labelBrowserVisible ? 'angle-down' : 'angle-right'} />
                 </button>
 
-                <div className="gf-form gf-form--grow flex-shrink-1 min-width-15">
+                <div className="flex-grow-1 min-width-15">
                   <MonacoQueryFieldWrapper
                     languageProvider={languageProvider}
                     history={history}

packages/grafana-prometheus/src/components/monaco-query-field/MonacoQueryField.tsx

@@ -83,6 +83,11 @@ const getStyles = (theme: GrafanaTheme2, placeholder: string) => {
     container: css({
       borderRadius: theme.shape.radius.default,
       border: `1px solid ${theme.components.input.borderColor}`,
+      display: 'flex',
+      flexDirection: 'row',
+      justifyContent: 'start',
+      alignItems: 'center',
+      height: '100%',
     }),
     placeholder: css({
       '::after': {

packages/grafana-ui/src/components/Monaco/ReactMonacoEditorLazy.tsx

@@ -1,5 +1,10 @@
+import { css } from '@emotion/css';
 import React from 'react';
 
+import { GrafanaTheme2 } from '@grafana/data';
+import { selectors } from '@grafana/e2e-selectors';
+
+import { useStyles2 } from '../../themes';
 import { useAsyncDependency } from '../../utils/useAsyncDependency';
 import { ErrorWithStack } from '../ErrorBoundary/ErrorWithStack';
 import { LoadingPlaceholder } from '../LoadingPlaceholder/LoadingPlaceholder';
@@ -11,13 +16,14 @@ import type { ReactMonacoEditorProps } from './types';
  * @internal
  * Experimental export
  **/
-export const ReactMonacoEditorLazy = (props: ReactMonacoEditorProps) => {
+const MonacoEditorLazy = (props: ReactMonacoEditorProps) => {
+  const styles = useStyles2(getStyles);
   const { loading, error, dependency } = useAsyncDependency(
     import(/* webpackChunkName: "react-monaco-editor" */ './ReactMonacoEditor')
   );
 
   if (loading) {
-    return <LoadingPlaceholder text={''} />;
+    return <LoadingPlaceholder text={'Loading editor'} className={styles.container} />;
   }
 
   if (error) {
@@ -31,5 +37,29 @@ export const ReactMonacoEditorLazy = (props: ReactMonacoEditorProps) => {
   }
 
   const ReactMonacoEditor = dependency.ReactMonacoEditor;
-  return <ReactMonacoEditor {...props} />;
+  return <ReactMonacoEditor {...props} loading={props.loading ?? null} />;
+};
+
+const getStyles = (theme: GrafanaTheme2) => {
+  return {
+    container: css({
+      marginBottom: 'unset',
+      marginLeft: theme.spacing(1),
+    }),
+  };
 };
+
+const withContainer = <P extends object>(Component: React.ComponentType<P>): React.ComponentType<P> => {
+  const WithContainer = (props: P) => (
+    // allow tests to easily determine if the code editor has rendered in any of its three states (loading, error, or ready)
+    <div data-testid={selectors.components.ReactMonacoEditor.container}>
+      <Component {...props} />
+    </div>
+  );
+
+  WithContainer.displayName = Component.displayName;
+
+  return WithContainer;
+};
+
+export const ReactMonacoEditorLazy = withContainer(MonacoEditorLazy);

public/app/plugins/datasource/loki/components/monaco-query-field/MonacoFieldWrapper.test.tsx

@@ -1,6 +1,8 @@
 import { render, screen, waitFor } from '@testing-library/react';
 import React from 'react';
 
+import { selectors } from '@grafana/e2e-selectors';
+
 import { createLokiDatasource } from '../../__mocks__/datasource';
 
 import { MonacoQueryFieldWrapper, Props } from './MonacoQueryFieldWrapper';
@@ -25,7 +27,8 @@ describe('MonacoFieldWrapper', () => {
     renderComponent();
 
     await waitFor(async () => {
-      expect(await screen.findByText('Loading...')).toBeInTheDocument();
+      const monacoEditor = await screen.findByTestId(selectors.components.ReactMonacoEditor.container);
+      expect(monacoEditor).toBeInTheDocument();
     });
   });
 });

public/app/plugins/datasource/loki/components/monaco-query-field/MonacoQueryField.test.tsx

@@ -1,6 +1,8 @@
 import { render, screen } from '@testing-library/react';
 import React from 'react';
 
+import { selectors } from '@grafana/e2e-selectors';
+
 import { createLokiDatasource } from '../../__mocks__/datasource';
 
 import MonacoQueryField from './MonacoQueryField';
@@ -31,6 +33,7 @@ describe('MonacoQueryField', () => {
   test('Renders with no errors', async () => {
     renderComponent();
 
-    expect(await screen.findByText('Loading...')).toBeInTheDocument();
+    const monacoEditor = await screen.findByTestId(selectors.components.ReactMonacoEditor.container);
+    expect(monacoEditor).toBeInTheDocument();
   });
 });

public/app/plugins/datasource/loki/querybuilder/components/LokiQueryCodeEditor.test.tsx

@@ -1,6 +1,8 @@
 import { render, screen } from '@testing-library/react';
 import React from 'react';
 
+import { selectors } from '@grafana/e2e-selectors';
+
 import { createLokiDatasource } from '../../__mocks__/datasource';
 import { LokiQuery } from '../../types';
 
@@ -32,7 +34,8 @@ describe('LokiQueryCodeEditor', () => {
     props.showExplain = true;
     props.datasource.metadataRequest = jest.fn().mockResolvedValue([]);
     render(<LokiQueryCodeEditor {...props} query={defaultQuery} />);
-    expect(await screen.findByText('Loading...')).toBeInTheDocument();
+    const monacoEditor = await screen.findByTestId(selectors.components.ReactMonacoEditor.container);
+    expect(monacoEditor).toBeInTheDocument();
     expect(screen.getByText(EXPLAIN_LABEL_FILTER_CONTENT)).toBeInTheDocument();
   });
 
@@ -40,7 +43,8 @@ describe('LokiQueryCodeEditor', () => {
     const props = createDefaultProps();
     props.datasource.metadataRequest = jest.fn().mockResolvedValue([]);
     render(<LokiQueryCodeEditor {...props} query={defaultQuery} />);
-    expect(await screen.findByText('Loading...')).toBeInTheDocument();
+    const monacoEditor = await screen.findByTestId(selectors.components.ReactMonacoEditor.container);
+    expect(monacoEditor).toBeInTheDocument();
     expect(screen.queryByText(EXPLAIN_LABEL_FILTER_CONTENT)).not.toBeInTheDocument();
   });
 });