Mobile,Desktop: Fixes #9522: Fix code block borders in headers of Beta Markdown editor (#9523)

packages/editor/CodeMirror/createEditor.test.ts

@@ -42,15 +42,12 @@ describe('createEditor', () => {
 
 		const headerLine = document.body.querySelector('.cm-headerLine')!;
 		expect(headerLine.textContent).toBe(headerLineText);
+		expect(getComputedStyle(headerLine).fontSize).toBe('1.6em');
 
 		// CodeMirror nests the tag that styles the header within .cm-headerLine:
 		//  <div class='cm-headerLine'><span class='someclass'>Testing...</span></div>
 		const headerLineContent = document.body.querySelectorAll('.cm-headerLine > span');
 		expect(headerLineContent.length).toBeGreaterThanOrEqual(1);
-		for (const part of headerLineContent) {
-			const style = getComputedStyle(part);
-			expect(style.fontSize).toBe('1.6em');
-		}
 
 		// Cleanup
 		editor.remove();

packages/editor/CodeMirror/markdown/decoratorExtension.ts

@@ -48,8 +48,28 @@ const blockQuoteDecoration = Decoration.line({
 	attributes: { class: 'cm-blockQuote' },
 });
 
-const headerLineDecoration = Decoration.line({
-	attributes: { class: 'cm-headerLine' },
+const header1LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h1 cm-headerLine' },
+});
+
+const header2LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h2 cm-headerLine' },
+});
+
+const header3LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h3 cm-headerLine' },
+});
+
+const header4LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h4 cm-headerLine' },
+});
+
+const header5LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h5 cm-headerLine' },
+});
+
+const header6LineDecoration = Decoration.line({
+	attributes: { class: 'cm-h6 cm-headerLine' },
 });
 
 const tableHeaderDecoration = Decoration.line({
@@ -72,6 +92,37 @@ const taskMarkerDecoration = Decoration.mark({
 	attributes: { class: 'cm-taskMarker' },
 });
 
+const nodeNameToLineDecoration: Record<string, Decoration> = {
+	'FencedCode': codeBlockDecoration,
+	'CodeBlock': codeBlockDecoration,
+	'BlockMath': mathBlockDecoration,
+	'Blockquote': blockQuoteDecoration,
+
+	'SetextHeading1': header1LineDecoration,
+	'ATXHeading1': header1LineDecoration,
+	'SetextHeading2': header2LineDecoration,
+	'ATXHeading2': header2LineDecoration,
+	'ATXHeading3': header3LineDecoration,
+	'ATXHeading4': header4LineDecoration,
+	'ATXHeading5': header5LineDecoration,
+	'ATXHeading6': header6LineDecoration,
+
+	'TableHeader': tableHeaderDecoration,
+	'TableDelimiter': tableDelimiterDecoration,
+	'TableRow': tableBodyDecoration,
+};
+
+const nodeNameToMarkDecoration: Record<string, Decoration> = {
+	'InlineCode': inlineCodeDecoration,
+	'URL': urlDecoration,
+	'InlineMath': inlineMathDecoration,
+	'HTMLTag': htmlTagNameDecoration,
+	'TagName': htmlTagNameDecoration,
+	'HorizontalRule': horizontalRuleDecoration,
+	'TaskMarker': taskMarkerDecoration,
+};
+
+
 type DecorationDescription = { pos: number; length?: number; decoration: Decoration };
 
 // Returns a set of [Decoration]s, associated with block syntax groups that require
@@ -116,58 +167,15 @@ const computeDecorations = (view: EditorView) => {
 				const viewFrom = Math.max(from, node.from);
 				const viewTo = Math.min(to, node.to);
 
-				switch (node.name) {
-				case 'FencedCode':
-				case 'CodeBlock':
-					addDecorationToLines(viewFrom, viewTo, codeBlockDecoration);
+				if (nodeNameToLineDecoration.hasOwnProperty(node.name)) {
+					const decoration = nodeNameToLineDecoration[node.name];
+					addDecorationToLines(viewFrom, viewTo, decoration);
 					blockDecorated = true;
-					break;
-				case 'BlockMath':
-					addDecorationToLines(viewFrom, viewTo, mathBlockDecoration);
-					blockDecorated = true;
-					break;
-				case 'Blockquote':
-					addDecorationToLines(viewFrom, viewTo, blockQuoteDecoration);
-					blockDecorated = true;
-					break;
-				case 'InlineMath':
-					addDecorationToRange(viewFrom, viewTo, inlineMathDecoration);
-					break;
-				case 'InlineCode':
-					addDecorationToRange(viewFrom, viewTo, inlineCodeDecoration);
-					break;
-				case 'URL':
-					addDecorationToRange(viewFrom, viewTo, urlDecoration);
-					break;
-				case 'SetextHeading1':
-				case 'SetextHeading2':
-				case 'ATXHeading1':
-				case 'ATXHeading2':
-				case 'ATXHeading3':
-				case 'ATXHeading4':
-				case 'ATXHeading5':
-				case 'ATXHeading6':
-					addDecorationToLines(viewFrom, viewTo, headerLineDecoration);
-					break;
-				case 'HTMLTag':
-				case 'TagName':
-					addDecorationToRange(viewFrom, viewTo, htmlTagNameDecoration);
-					break;
-				case 'TableHeader':
-					addDecorationToLines(viewFrom, viewTo, tableHeaderDecoration);
-					break;
-				case 'TableDelimiter':
-					addDecorationToLines(viewFrom, viewTo, tableDelimiterDecoration);
-					break;
-				case 'TableRow':
-					addDecorationToLines(viewFrom, viewTo, tableBodyDecoration);
-					break;
-				case 'HorizontalRule':
-					addDecorationToRange(viewFrom, viewTo, horizontalRuleDecoration);
-					break;
-				case 'TaskMarker':
-					addDecorationToRange(viewFrom, viewTo, taskMarkerDecoration);
-					break;
+				}
+
+				if (nodeNameToMarkDecoration.hasOwnProperty(node.name)) {
+					const decoration = nodeNameToMarkDecoration[node.name];
+					addDecorationToRange(viewFrom, viewTo, decoration);
 				}
 
 				// Only block decorations will have differing first and last lines

packages/editor/CodeMirror/theme.ts

@@ -78,6 +78,11 @@ const createTheme = (theme: any): Extension[] => {
 	// be at least this specific.
 	const selectionBackgroundSelector = '&.cm-focused > .cm-scroller > .cm-selectionLayer .cm-selectionBackground';
 
+	const baseHeadingStyle = {
+		fontWeight: 'bold',
+		fontFamily: theme.fontFamily,
+	};
+
 	const codeMirrorTheme = EditorView.theme({
 		'&': baseGlobalStyle,
 
@@ -145,7 +150,7 @@ const createTheme = (theme: any): Extension[] => {
 		// span with a larger font-size, the .cm-inlineCode's bounding box won't
 		// be big enough for its content.
 		// As such, we need to style whichever element directly wraps its content.
-		'& .cm-headerLine > .cm-inlineCode > *, & :not(.cm-headerLine) > .cm-inlineCode': {
+		'& .cm-inlineCode': {
 			borderWidth: '1px',
 			borderStyle: 'solid',
 			borderColor: isDarkTheme ? 'rgba(200, 200, 200, 0.5)' : 'rgba(100, 100, 100, 0.5)',
@@ -166,6 +171,34 @@ const createTheme = (theme: any): Extension[] => {
 			opacity: theme.isDesktop ? 0.6 : 1,
 		},
 
+		// Applying font size changes with CSS rather than the theme below works
+		// around an issue where the border for code blocks in headings was too
+		// small.
+		'& .cm-h1': {
+			...baseHeadingStyle,
+			fontSize: '1.6em',
+		},
+		'& .cm-h2': {
+			...baseHeadingStyle,
+			fontSize: '1.4em',
+		},
+		'& .cm-h3': {
+			...baseHeadingStyle,
+			fontSize: '1.3em',
+		},
+		'& .cm-h4': {
+			...baseHeadingStyle,
+			fontSize: '1.2em',
+		},
+		'& .cm-h5': {
+			...baseHeadingStyle,
+			fontSize: '1.1em',
+		},
+		'& .cm-h6': {
+			...baseHeadingStyle,
+			fontSize: '1.0em',
+		},
+
 		// Style the search widget. Use ':root' to increase the selector's precedence
 		// (override the existing preset styles).
 		':root & .cm-panel.cm-search': {
@@ -176,11 +209,6 @@ const createTheme = (theme: any): Extension[] => {
 		},
 	}, { dark: isDarkTheme });
 
-	const baseHeadingStyle = {
-		fontWeight: 'bold',
-		fontFamily: theme.fontFamily,
-	};
-
 	const highlightingStyle = HighlightStyle.define([
 		{
 			tag: tags.strong,
@@ -190,36 +218,6 @@ const createTheme = (theme: any): Extension[] => {
 			tag: tags.emphasis,
 			fontStyle: 'italic',
 		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading1,
-			fontSize: '1.6em',
-		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading2,
-			fontSize: '1.4em',
-		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading3,
-			fontSize: '1.3em',
-		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading4,
-			fontSize: '1.2em',
-		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading5,
-			fontSize: '1.1em',
-		},
-		{
-			...baseHeadingStyle,
-			tag: tags.heading6,
-			fontSize: '1.0em',
-		},
 		{
 			tag: tags.list,
 			fontFamily: theme.fontFamily,