Only show a certain subset of decorations when they are collapsed

src/vs/editor/browser/viewParts/decorations/decorations.ts

@@ -146,24 +146,26 @@ export class DecorationsOverlay extends DynamicViewOverlay {
 		let visibleStartLineNumber = ctx.visibleRange.startLineNumber;
 
 		for (let i = 0, lenI = decorations.length; i < lenI; i++) {
-			let d = decorations[i];
+			const d = decorations[i];
 
 			if (d.source.options.isWholeLine) {
 				continue;
 			}
 
-			let className = d.source.options.className;
+			const className = d.source.options.className;
 
 			let linesVisibleRanges = ctx.linesVisibleRangesForRange(d.range, /*TODO@Alex*/className === 'findMatch');
 			if (!linesVisibleRanges) {
 				continue;
 			}
 
+			const showIfCollapsed = d.source.options.showIfCollapsed;
+
 			for (let j = 0, lenJ = linesVisibleRanges.length; j < lenJ; j++) {
 				let lineVisibleRanges = linesVisibleRanges[j];
-				let lineIndex = lineVisibleRanges.lineNumber - visibleStartLineNumber;
+				const lineIndex = lineVisibleRanges.lineNumber - visibleStartLineNumber;
 
-				if (lineVisibleRanges.ranges.length === 1) {
+				if (showIfCollapsed && lineVisibleRanges.ranges.length === 1) {
 					const singleVisibleRange = lineVisibleRanges.ranges[0];
 					if (singleVisibleRange.width === 0) {
 						// collapsed range case => make the decoration visible by faking its width
@@ -172,8 +174,8 @@ export class DecorationsOverlay extends DynamicViewOverlay {
 				}
 
 				for (let k = 0, lenK = lineVisibleRanges.ranges.length; k < lenK; k++) {
-					let visibleRange = lineVisibleRanges.ranges[k];
-					let decorationOutput = (
+					const visibleRange = lineVisibleRanges.ranges[k];
+					const decorationOutput = (
 						'<div class="cdr '
 						+ className
 						+ '" style="left:'

src/vs/editor/common/editorCommon.ts

@@ -85,6 +85,11 @@ export interface IModelDecorationOptions {
 	 * Should the decoration expand to encompass a whole line.
 	 */
 	isWholeLine?: boolean;
+	/**
+	 * Always render the decoration (even when the range it encompasses is collapsed).
+	 * @internal
+	 */
+	showIfCollapsed?: boolean;
 	/**
 	 * @deprecated : Use `overviewRuler` instead
 	 */

src/vs/editor/common/model/textModelWithDecorations.ts

@@ -846,6 +846,7 @@ export class ModelDecorationOptions implements editorCommon.IModelDecorationOpti
 	hoverMessage: MarkedString | MarkedString[];
 	glyphMarginHoverMessage: MarkedString | MarkedString[];
 	isWholeLine: boolean;
+	showIfCollapsed: boolean;
 	showInOverviewRuler: string;
 	overviewRuler: editorCommon.IModelDecorationOverviewRulerOptions;
 	glyphMarginClassName: string;
@@ -861,6 +862,7 @@ export class ModelDecorationOptions implements editorCommon.IModelDecorationOpti
 		this.hoverMessage = options.hoverMessage || [];
 		this.glyphMarginHoverMessage = options.glyphMarginHoverMessage || strings.empty;
 		this.isWholeLine = options.isWholeLine || false;
+		this.showIfCollapsed = options.showIfCollapsed || false;
 		this.overviewRuler = _normalizeOverviewRulerOptions(options.overviewRuler, options.showInOverviewRuler);
 		this.glyphMarginClassName = options.glyphMarginClassName ? cleanClassName(options.glyphMarginClassName) : strings.empty;
 		this.linesDecorationsClassName = options.linesDecorationsClassName ? cleanClassName(options.linesDecorationsClassName) : strings.empty;
@@ -883,6 +885,7 @@ export class ModelDecorationOptions implements editorCommon.IModelDecorationOpti
 			this.stickiness === other.stickiness
 			&& this.className === other.className
 			&& this.isWholeLine === other.isWholeLine
+			&& this.showIfCollapsed === other.showIfCollapsed
 			&& this.showInOverviewRuler === other.showInOverviewRuler
 			&& this.glyphMarginClassName === other.glyphMarginClassName
 			&& this.linesDecorationsClassName === other.linesDecorationsClassName

src/vs/editor/common/services/modelServiceImpl.ts

@@ -157,6 +157,7 @@ class ModelMarkerHandler {
 			stickiness: editorCommon.TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
 			className,
 			hoverMessage,
+			showIfCollapsed: true,
 			overviewRuler: {
 				color,
 				darkColor,

src/vs/editor/contrib/find/common/findDecorations.ts

@@ -154,6 +154,7 @@ export class FindDecorations implements IDisposable {
 		return {
 			stickiness: editorCommon.TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
 			className: isCurrent ? 'currentFindMatch' : 'findMatch',
+			showIfCollapsed: true,
 			overviewRuler: {
 				color: 'rgba(246, 185, 77, 0.7)',
 				darkColor: 'rgba(246, 185, 77, 0.7)',