Use better check for equality that works with floats and make sure the position of a hit test result is always contained in the range

Author: alexdima

src/vs/editor/browser/controller/mouseTarget.ts

@@ -495,15 +495,17 @@ export class MouseTargetFactory {
 		const request = new HitTestRequest(ctx, editorPos, pos, relativePos, target);
 		try {
 			const r = MouseTargetFactory._createMouseTarget(ctx, request, false);
-			// console.log(MouseTarget.toString(r));
 
 			if (r.type === MouseTargetType.CONTENT_TEXT) {
 				// Snap to the nearest soft tab boundary if atomic soft tabs are enabled.
 				if (ctx.stickyTabStops && r.position !== null) {
 					const position = MouseTargetFactory._snapToSoftTabBoundary(r.position, ctx.viewModel);
-					return request.fulfillContentText(position, r.range, r.detail);
+					const range = EditorRange.fromPositions(position, position).plusRange(r.range);
+					return request.fulfillContentText(position, range, r.detail);
 				}
 			}
+
+			// console.log(MouseTarget.toString(r));
 			return r;
 		} catch (err) {
 			// console.log(err);
@@ -782,12 +784,10 @@ export class MouseTargetFactory {
 		const lineNumber = pos.lineNumber;
 		const column = pos.column;
 
-		const mouseContentHorizontalOffset = Math.floor(request.mouseContentHorizontalOffset);
-
 		const lineWidth = ctx.getLineWidth(lineNumber);
 
-		if (mouseContentHorizontalOffset > lineWidth) {
-			const detail = createEmptyContentDataInLines(mouseContentHorizontalOffset - lineWidth);
+		if (request.mouseContentHorizontalOffset > lineWidth) {
+			const detail = createEmptyContentDataInLines(request.mouseContentHorizontalOffset - lineWidth);
 			return request.fulfillContentEmpty(pos, detail);
 		}
 
@@ -799,7 +799,7 @@ export class MouseTargetFactory {
 
 		const columnHorizontalOffset = visibleRange.left;
 
-		if (mouseContentHorizontalOffset === columnHorizontalOffset) {
+		if (Math.abs(request.mouseContentHorizontalOffset - columnHorizontalOffset) < 1) {
 			return request.fulfillContentText(pos, null, { mightBeForeignElement: !!injectedText, injectedText });
 		}
 
@@ -833,15 +833,15 @@ export class MouseTargetFactory {
 		for (let i = 1; i < points.length; i++) {
 			const prev = points[i - 1];
 			const curr = points[i];
-			if (prev.offset <= mouseContentHorizontalOffset && mouseContentHorizontalOffset <= curr.offset) {
+			if (prev.offset <= request.mouseContentHorizontalOffset && request.mouseContentHorizontalOffset <= curr.offset) {
 				rng = new EditorRange(lineNumber, prev.column, lineNumber, curr.column);
 
 				// See https://github.com/microsoft/vscode/issues/152819
 				// Due to the use of zwj, the browser's hit test result is skewed towards the left
 				// Here we try to correct that if the mouse horizontal offset is closer to the right than the left
 
-				const prevDelta = Math.abs(prev.offset - mouseContentHorizontalOffset);
-				const nextDelta = Math.abs(curr.offset - mouseContentHorizontalOffset);
+				const prevDelta = Math.abs(prev.offset - request.mouseContentHorizontalOffset);
+				const nextDelta = Math.abs(curr.offset - request.mouseContentHorizontalOffset);
 
 				pos = (
 					prevDelta < nextDelta