From 95355e457d0abc852e4a6fdb310eb853de041814 Mon Sep 17 00:00:00 2001
From: Henning Dieterichs <hdieterichs@microsoft.com>
Date: Tue, 17 Aug 2021 13:25:10 +0200
Subject: [PATCH] When injected text changes, only call setCursors when the
 cursor position also changed. This fixes #130982.

---
 src/vs/editor/common/controller/cursor.ts | 32 ++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/vs/editor/common/controller/cursor.ts b/src/vs/editor/common/controller/cursor.ts
index a14ba69259f..d4e43cd3a00 100644
--- a/src/vs/editor/common/controller/cursor.ts
+++ b/src/vs/editor/common/controller/cursor.ts
@@ -332,7 +332,15 @@ export class CursorsController extends Disposable {
 		if (e instanceof ModelInjectedTextChangedEvent) {
 			// If injected texts change, the view positions of all cursors need to be updated.
 			const selectionsFromMarkers = this._cursors.readSelectionFromMarkers();
-			this.setStates(eventsCollector, 'modelChange', CursorChangeReason.RecoverFromMarkers, CursorState.fromModelSelections(selectionsFromMarkers));
+			const newState = CursorState.fromModelSelections(selectionsFromMarkers);
+
+			if (didStateChange(this.getCursorStates(), newState || [])) {
+				// setStates might remove markers, which could trigger a decoration change.
+				// If there are injected text decorations for that line, `onModelContentChanged` is emitted again
+				// and an endless recursion happens.
+				// This is why we only call setStates if we really need to (this fixes recursion).
+				this.setStates(eventsCollector, 'modelChange', CursorChangeReason.RecoverFromMarkers, newState);
+			}
 		} else {
 			this._knownModelVersionId = e.versionId;
 			if (this._isHandling) {
@@ -719,6 +727,28 @@ export class CursorsController extends Disposable {
 	}
 }
 
+function didStateChange(currentStates: CursorState[], newStates: PartialCursorState[]): boolean {
+	if (currentStates.length !== newStates.length) {
+		return true;
+	}
+
+	for (let i = 0; i < currentStates.length; i++) {
+		const curState = currentStates[i];
+		const newState = newStates[i];
+		if (newState.modelState) {
+			if (!newState.modelState.equals(curState.modelState)) {
+				return true;
+			}
+		}
+		if (newState.viewState) {
+			if (!newState.viewState.equals(curState.viewState)) {
+				return true;
+			}
+		}
+	}
+	return false;
+}
+
 interface IExecContext {
 	readonly model: ITextModel;
 	readonly selectionsBefore: Selection[];