[v11.5.x] CodeEditor: Fix cursor alignment (#99863)

CodeEditor: Fix cursor alignment (#99090)

* remeasure fonts once they've loaded

* add test mock

* fix unit test

* remeasure fonts after the editor has mounted just to be safe

(cherry picked from commit 8e59f618c1)

Co-authored-by: Ashley Harrison <ashley.harrison@grafana.com>

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

@@ -11,7 +11,7 @@ import type { ReactMonacoEditorProps } from './types';
 monacoEditorLoader.config({ monaco });
 
 export const ReactMonacoEditor = (props: ReactMonacoEditorProps) => {
-  const { beforeMount, options, ...restProps } = props;
+  const { beforeMount, onMount, options, ...restProps } = props;
 
   const theme = useTheme2();
   const onMonacoBeforeMount = useCallback(
@@ -31,6 +31,15 @@ export const ReactMonacoEditor = (props: ReactMonacoEditorProps) => {
       }}
       theme={theme.isDark ? 'grafana-dark' : 'grafana-light'}
       beforeMount={onMonacoBeforeMount}
+      onMount={(editor, monaco) => {
+        // we use a custom font in our monaco editor
+        // we need monaco to remeasure the fonts after they are loaded to prevent alignment issues
+        // see https://github.com/microsoft/monaco-editor/issues/648#issuecomment-564978560
+        document.fonts.ready.then(() => {
+          monaco.editor.remeasureFonts();
+        });
+        onMount?.(editor, monaco);
+      }}
     />
   );
 };

public/app/plugins/panel/datagrid/DataGridPanel.test.tsx

@@ -59,16 +59,18 @@ describe('DataGrid', () => {
       jest.clearAllMocks();
     });
 
-    it('converts dataframe values to cell values properly', () => {
+    it('converts dataframe values to cell values properly', async () => {
       jest.useFakeTimers();
       render(<DataGridPanel {...props} />);
       prep(false);
 
+      await waitFor(() => {
         expect(screen.getByTestId('glide-cell-1-0')).toHaveTextContent('1');
         expect(screen.getByTestId('glide-cell-2-1')).toHaveTextContent('b');
         expect(screen.getByTestId('glide-cell-3-2')).toHaveTextContent('c');
         expect(screen.getByTestId('glide-cell-3-3')).toHaveTextContent('d');
       });
+    });
 
     it('should open context menu on right click', async () => {
       jest.useFakeTimers();

public/test/jest-setup.ts

@@ -61,6 +61,9 @@ const mockIntersectionObserver = jest
     disconnect: jest.fn(),
   }));
 global.IntersectionObserver = mockIntersectionObserver;
+Object.defineProperty(document, 'fonts', {
+  value: { ready: Promise.resolve({}) },
+});
 
 global.TextEncoder = TextEncoder;
 global.TextDecoder = TextDecoder;