From 47a6d93693f209da68d24699d66353d3c60aec9e Mon Sep 17 00:00:00 2001
From: Alex Dima <alexdima@microsoft.com>
Date: Thu, 24 Sep 2020 09:10:14 +0200
Subject: [PATCH] Instantiate text models even if the undo / redo stack for a
 text model contains foreign elements (#101789)

---
 .../common/services/modelServiceImpl.ts       | 21 ++-----------------
 .../services/modelUndoRedoParticipant.ts      | 10 +++------
 2 files changed, 5 insertions(+), 26 deletions(-)

diff --git a/src/vs/editor/common/services/modelServiceImpl.ts b/src/vs/editor/common/services/modelServiceImpl.ts
index 576a7dd4ce863..b21a32c25dc63 100644
--- a/src/vs/editor/common/services/modelServiceImpl.ts
+++ b/src/vs/editor/common/services/modelServiceImpl.ts
@@ -24,9 +24,9 @@ import { RunOnceScheduler } from 'vs/base/common/async';
 import { CancellationTokenSource } from 'vs/base/common/cancellation';
 import { IThemeService } from 'vs/platform/theme/common/themeService';
 import { ILogService } from 'vs/platform/log/common/log';
-import { IUndoRedoService, IUndoRedoElement, IPastFutureElements, ResourceEditStackSnapshot } from 'vs/platform/undoRedo/common/undoRedo';
+import { IUndoRedoService, ResourceEditStackSnapshot } from 'vs/platform/undoRedo/common/undoRedo';
 import { StringSHA1 } from 'vs/base/common/hash';
-import { SingleModelEditStackElement, MultiModelEditStackElement, EditStackElement, isEditStackElement } from 'vs/editor/common/model/editStack';
+import { EditStackElement, isEditStackElement } from 'vs/editor/common/model/editStack';
 import { Schemas } from 'vs/base/common/network';
 import { SemanticTokensProviderStyling, toMultilineTokens2 } from 'vs/editor/common/services/semanticTokensProviderStyling';
 
@@ -118,23 +118,6 @@ export interface EditStackPastFutureElements {
 	future: EditStackElement[];
 }
 
-export function isEditStackPastFutureElements(undoElements: IPastFutureElements): undoElements is EditStackPastFutureElements {
-	return (isEditStackElements(undoElements.past) && isEditStackElements(undoElements.future));
-}
-
-function isEditStackElements(elements: IUndoRedoElement[]): elements is EditStackElement[] {
-	for (const element of elements) {
-		if (element instanceof SingleModelEditStackElement) {
-			continue;
-		}
-		if (element instanceof MultiModelEditStackElement) {
-			continue;
-		}
-		return false;
-	}
-	return true;
-}
-
 class DisposedModelInfo {
 	constructor(
 		public readonly uri: URI,
diff --git a/src/vs/editor/common/services/modelUndoRedoParticipant.ts b/src/vs/editor/common/services/modelUndoRedoParticipant.ts
index 0862ccf8d6e26..6a03af9e80f3d 100644
--- a/src/vs/editor/common/services/modelUndoRedoParticipant.ts
+++ b/src/vs/editor/common/services/modelUndoRedoParticipant.ts
@@ -6,8 +6,7 @@
 import { IModelService } from 'vs/editor/common/services/modelService';
 import { ITextModelService } from 'vs/editor/common/services/resolverService';
 import { Disposable, IDisposable, dispose } from 'vs/base/common/lifecycle';
-import { IUndoRedoService, UndoRedoElementType } from 'vs/platform/undoRedo/common/undoRedo';
-import { isEditStackPastFutureElements } from 'vs/editor/common/services/modelServiceImpl';
+import { IUndoRedoService } from 'vs/platform/undoRedo/common/undoRedo';
 import { IUndoRedoDelegate, MultiModelEditStackElement } from 'vs/editor/common/model/editStack';
 
 export class ModelUndoRedoParticipant extends Disposable implements IUndoRedoDelegate {
@@ -23,16 +22,13 @@ export class ModelUndoRedoParticipant extends Disposable implements IUndoRedoDel
 			if (elements.past.length === 0 && elements.future.length === 0) {
 				return;
 			}
-			if (!isEditStackPastFutureElements(elements)) {
-				return;
-			}
 			for (const element of elements.past) {
-				if (element.type === UndoRedoElementType.Workspace) {
+				if (element instanceof MultiModelEditStackElement) {
 					element.setDelegate(this);
 				}
 			}
 			for (const element of elements.future) {
-				if (element.type === UndoRedoElementType.Workspace) {
+				if (element instanceof MultiModelEditStackElement) {
 					element.setDelegate(this);
 				}
 			}