Add editor.disableMonospaceOptimizations (closes #19062)

src/vs/editor/browser/viewParts/lines/viewLine.ts

@@ -70,7 +70,7 @@ export class ViewLine implements IVisibleLineData {
 	private _renderWhitespace: 'none' | 'boundary' | 'all';
 	private _renderControlCharacters: boolean;
 	private _spaceWidth: number;
-	private _fontIsMonospace: boolean;
+	private _useMonospaceOptimizations: boolean;
 	private _lineHeight: number;
 	private _stopRenderingLineAfter: number;
 
@@ -83,7 +83,10 @@ export class ViewLine implements IVisibleLineData {
 		this._renderWhitespace = this._context.configuration.editor.viewInfo.renderWhitespace;
 		this._renderControlCharacters = this._context.configuration.editor.viewInfo.renderControlCharacters;
 		this._spaceWidth = this._context.configuration.editor.fontInfo.spaceWidth;
-		this._fontIsMonospace = this._context.configuration.editor.fontInfo.isMonospace;
+		this._useMonospaceOptimizations = (
+			this._context.configuration.editor.fontInfo.isMonospace
+			&& !this._context.configuration.editor.viewInfo.disableMonospaceOptimizations
+		);
 		this._lineHeight = this._context.configuration.editor.lineHeight;
 		this._stopRenderingLineAfter = this._context.configuration.editor.viewInfo.stopRenderingLineAfter;
 
@@ -126,10 +129,20 @@ export class ViewLine implements IVisibleLineData {
 			this._isMaybeInvalid = true;
 			this._renderControlCharacters = this._context.configuration.editor.viewInfo.renderControlCharacters;
 		}
+		if (e.viewInfo.disableMonospaceOptimizations) {
+			this._isMaybeInvalid = true;
+			this._useMonospaceOptimizations = (
+				this._context.configuration.editor.fontInfo.isMonospace
+				&& !this._context.configuration.editor.viewInfo.disableMonospaceOptimizations
+			);
+		}
 		if (e.fontInfo) {
 			this._isMaybeInvalid = true;
 			this._spaceWidth = this._context.configuration.editor.fontInfo.spaceWidth;
-			this._fontIsMonospace = this._context.configuration.editor.fontInfo.isMonospace;
+			this._useMonospaceOptimizations = (
+				this._context.configuration.editor.fontInfo.isMonospace
+				&& !this._context.configuration.editor.viewInfo.disableMonospaceOptimizations
+			);
 		}
 		if (e.lineHeight) {
 			this._isMaybeInvalid = true;
@@ -153,7 +166,7 @@ export class ViewLine implements IVisibleLineData {
 		const lineContent = model.getLineContent(lineNumber);
 
 		let renderLineInput = new RenderLineInput(
-			this._fontIsMonospace,
+			this._useMonospaceOptimizations,
 			lineContent,
 			model.mightContainRTL(),
 			model.getLineMinColumn(lineNumber) - 1,
@@ -174,7 +187,7 @@ export class ViewLine implements IVisibleLineData {
 		const output = renderViewLine(renderLineInput);
 
 		let renderedViewLine: IRenderedViewLine = null;
-		if (canUseFastRenderedViewLine && this._fontIsMonospace && !output.containsForeignElements) {
+		if (canUseFastRenderedViewLine && this._useMonospaceOptimizations && !output.containsForeignElements) {
 			let isRegularASCII = true;
 			if (model.mightContainNonBasicASCII()) {
 				isRegularASCII = strings.isBasicASCII(lineContent);

src/vs/editor/browser/widget/diffEditorWidget.ts

@@ -1894,7 +1894,7 @@ class InlineViewZonesComputer extends ViewZonesComputer {
 		let actualDecorations = Decoration.filter(decorations, lineNumber, 1, lineContent.length + 1);
 
 		let r = renderViewLine(new RenderLineInput(
-			config.fontInfo.isMonospace,
+			(config.fontInfo.isMonospace && !config.viewInfo.disableMonospaceOptimizations),
 			lineContent,
 			originalModel.mightContainRTL(),
 			0,

src/vs/editor/common/config/commonEditorConfig.ts

@@ -252,6 +252,7 @@ class InternalEditorOptionsHelper {
 		let viewInfo = new editorCommon.InternalEditorViewOptions({
 			theme: opts.theme,
 			canUseTranslate3d: canUseTranslate3d,
+			disableMonospaceOptimizations: toBoolean(opts.disableMonospaceOptimizations),
 			experimentalScreenReader: toBoolean(opts.experimentalScreenReader),
 			rulers: toSortedIntegerArray(opts.rulers),
 			ariaLabel: String(opts.ariaLabel),

src/vs/editor/common/config/defaultConfig.ts

@@ -63,6 +63,7 @@ class ConfigClass implements IConfiguration {
 			cursorStyle: 'line',
 			fontLigatures: false,
 			disableTranslate3d: false,
+			disableMonospaceOptimizations: false,
 			hideCursorInOverviewRuler: false,
 			scrollBeyondLastLine: true,
 			automaticLayout: false,

src/vs/editor/common/editorCommon.ts

@@ -292,6 +292,11 @@ export interface IEditorOptions {
 	 * Defaults to false.
 	 */
 	disableTranslate3d?: boolean;
+	/**
+	 * Disable the optimizations for monospace fonts.
+	 * Defaults to false.
+	 */
+	disableMonospaceOptimizations?: boolean;
 	/**
 	 * Should the cursor be hidden in the overview ruler.
 	 * Defaults to false.
@@ -663,6 +668,7 @@ export class InternalEditorViewOptions {
 
 	readonly theme: string;
 	readonly canUseTranslate3d: boolean;
+	readonly disableMonospaceOptimizations: boolean;
 	readonly experimentalScreenReader: boolean;
 	readonly rulers: number[];
 	readonly ariaLabel: string;
@@ -694,6 +700,7 @@ export class InternalEditorViewOptions {
 	constructor(source: {
 		theme: string;
 		canUseTranslate3d: boolean;
+		disableMonospaceOptimizations: boolean;
 		experimentalScreenReader: boolean;
 		rulers: number[];
 		ariaLabel: string;
@@ -721,6 +728,7 @@ export class InternalEditorViewOptions {
 	}) {
 		this.theme = String(source.theme);
 		this.canUseTranslate3d = Boolean(source.canUseTranslate3d);
+		this.disableMonospaceOptimizations = Boolean(source.disableMonospaceOptimizations);
 		this.experimentalScreenReader = Boolean(source.experimentalScreenReader);
 		this.rulers = InternalEditorViewOptions._toSortedIntegerArray(source.rulers);
 		this.ariaLabel = String(source.ariaLabel);
@@ -782,6 +790,7 @@ export class InternalEditorViewOptions {
 		return (
 			this.theme === other.theme
 			&& this.canUseTranslate3d === other.canUseTranslate3d
+			&& this.disableMonospaceOptimizations === other.disableMonospaceOptimizations
 			&& this.experimentalScreenReader === other.experimentalScreenReader
 			&& InternalEditorViewOptions._numberArraysEqual(this.rulers, other.rulers)
 			&& this.ariaLabel === other.ariaLabel
@@ -816,6 +825,7 @@ export class InternalEditorViewOptions {
 		return {
 			theme: this.theme !== newOpts.theme,
 			canUseTranslate3d: this.canUseTranslate3d !== newOpts.canUseTranslate3d,
+			disableMonospaceOptimizations: this.disableMonospaceOptimizations !== newOpts.disableMonospaceOptimizations,
 			experimentalScreenReader: this.experimentalScreenReader !== newOpts.experimentalScreenReader,
 			rulers: (!InternalEditorViewOptions._numberArraysEqual(this.rulers, newOpts.rulers)),
 			ariaLabel: this.ariaLabel !== newOpts.ariaLabel,
@@ -854,6 +864,7 @@ export class InternalEditorViewOptions {
 export interface IViewConfigurationChangedEvent {
 	readonly theme: boolean;
 	readonly canUseTranslate3d: boolean;
+	readonly disableMonospaceOptimizations: boolean;
 	readonly experimentalScreenReader: boolean;
 	readonly rulers: boolean;
 	readonly ariaLabel: boolean;

src/vs/editor/common/viewLayout/viewLineRenderer.ts

@@ -17,7 +17,7 @@ export const enum RenderWhitespace {
 
 export class RenderLineInput {
 
-	public readonly fontIsMonospace: boolean;
+	public readonly useMonospaceOptimizations: boolean;
 	public readonly lineContent: string;
 	public readonly mightContainRTL: boolean;
 	public readonly fauxIndentLength: number;
@@ -30,7 +30,7 @@ export class RenderLineInput {
 	public readonly renderControlCharacters: boolean;
 
 	constructor(
-		fontIsMonospace: boolean,
+		useMonospaceOptimizations: boolean,
 		lineContent: string,
 		mightContainRTL: boolean,
 		fauxIndentLength: number,
@@ -42,7 +42,7 @@ export class RenderLineInput {
 		renderWhitespace: 'none' | 'boundary' | 'all',
 		renderControlCharacters: boolean,
 	) {
-		this.fontIsMonospace = fontIsMonospace;
+		this.useMonospaceOptimizations = useMonospaceOptimizations;
 		this.lineContent = lineContent;
 		this.mightContainRTL = mightContainRTL;
 		this.fauxIndentLength = fauxIndentLength;
@@ -63,7 +63,7 @@ export class RenderLineInput {
 
 	public equals(other: RenderLineInput): boolean {
 		return (
-			this.fontIsMonospace === other.fontIsMonospace
+			this.useMonospaceOptimizations === other.useMonospaceOptimizations
 			&& this.lineContent === other.lineContent
 			&& this.mightContainRTL === other.mightContainRTL
 			&& this.fauxIndentLength === other.fauxIndentLength
@@ -249,7 +249,7 @@ class ResolvedRenderLineInput {
 }
 
 function resolveRenderLineInput(input: RenderLineInput): ResolvedRenderLineInput {
-	const fontIsMonospace = input.fontIsMonospace;
+	const useMonospaceOptimizations = input.useMonospaceOptimizations;
 	const lineContent = input.lineContent;
 
 	let isOverflowing: boolean;
@@ -265,7 +265,7 @@ function resolveRenderLineInput(input: RenderLineInput): ResolvedRenderLineInput
 
 	let tokens = removeOverflowing(input.lineTokens, len);
 	if (input.renderWhitespace === RenderWhitespace.All || input.renderWhitespace === RenderWhitespace.Boundary) {
-		tokens = _applyRenderWhitespace(lineContent, len, tokens, input.fauxIndentLength, input.tabSize, fontIsMonospace, input.renderWhitespace === RenderWhitespace.Boundary);
+		tokens = _applyRenderWhitespace(lineContent, len, tokens, input.fauxIndentLength, input.tabSize, useMonospaceOptimizations, input.renderWhitespace === RenderWhitespace.Boundary);
 	}
 	let containsForeignElements = false;
 	if (input.lineDecorations.length > 0) {
@@ -287,7 +287,7 @@ function resolveRenderLineInput(input: RenderLineInput): ResolvedRenderLineInput
 	}
 
 	return new ResolvedRenderLineInput(
-		fontIsMonospace,
+		useMonospaceOptimizations,
 		lineContent,
 		len,
 		isOverflowing,
@@ -369,7 +369,7 @@ function splitLargeTokens(tokens: ViewLineToken[]): ViewLineToken[] {
  * Moreover, a token is created for every visual indent because on some fonts the glyphs used for rendering whitespace (→ or ·) do not have the same width as  .
  * The rendering phase will generate `style="width:..."` for these tokens.
  */
-function _applyRenderWhitespace(lineContent: string, len: number, tokens: ViewLineToken[], fauxIndentLength: number, tabSize: number, fontIsMonospace: boolean, onlyBoundary: boolean): ViewLineToken[] {
+function _applyRenderWhitespace(lineContent: string, len: number, tokens: ViewLineToken[], fauxIndentLength: number, tabSize: number, useMonospaceOptimizations: boolean, onlyBoundary: boolean): ViewLineToken[] {
 
 	let result: ViewLineToken[] = [], resultLen = 0;
 	let tokenIndex = 0;
@@ -431,7 +431,7 @@ function _applyRenderWhitespace(lineContent: string, len: number, tokens: ViewLi
 
 		if (wasInWhitespace) {
 			// was in whitespace token
-			if (!isInWhitespace || (!fontIsMonospace && tmpIndent >= tabSize)) {
+			if (!isInWhitespace || (!useMonospaceOptimizations && tmpIndent >= tabSize)) {
 				// leaving whitespace token or entering a new indent
 				result[resultLen++] = new ViewLineToken(charIndex, 'vs-whitespace');
 				tmpIndent = tmpIndent % tabSize;

src/vs/monaco.d.ts

@@ -1210,6 +1210,11 @@ declare module monaco.editor {
          * Defaults to false.
          */
         disableTranslate3d?: boolean;
+        /**
+         * Disable the optimizations for monospace fonts.
+         * Defaults to false.
+         */
+        disableMonospaceOptimizations?: boolean;
         /**
          * Should the cursor be hidden in the overview ruler.
          * Defaults to false.
@@ -1474,6 +1479,7 @@ declare module monaco.editor {
         readonly _internalEditorViewOptionsBrand: void;
         readonly theme: string;
         readonly canUseTranslate3d: boolean;
+        readonly disableMonospaceOptimizations: boolean;
         readonly experimentalScreenReader: boolean;
         readonly rulers: number[];
         readonly ariaLabel: string;
@@ -1503,6 +1509,7 @@ declare module monaco.editor {
     export interface IViewConfigurationChangedEvent {
         readonly theme: boolean;
         readonly canUseTranslate3d: boolean;
+        readonly disableMonospaceOptimizations: boolean;
         readonly experimentalScreenReader: boolean;
         readonly rulers: boolean;
         readonly ariaLabel: boolean;