fixes #42909

src/vs/workbench/api/electron-browser/mainThreadEditors.ts

@@ -247,11 +247,17 @@ export class MainThreadTextEditors implements MainThreadTextEditorsShape {
 		const diffEditors = this._codeEditorService.listDiffEditors();
 		const [diffEditor] = diffEditors.filter(d => d.getOriginalEditor().getId() === codeEditorId || d.getModifiedEditor().getId() === codeEditorId);
 
-		if (!diffEditor) {
-			return TPromise.as([]);
+		if (diffEditor) {
+			return TPromise.as(diffEditor.getLineChanges());
 		}
 
-		return TPromise.as(diffEditor.getLineChanges());
+		const dirtyDiffContribution = codeEditor.getContribution('editor.contrib.dirtydiff');
+
+		if (dirtyDiffContribution) {
+			return TPromise.as((dirtyDiffContribution as any).getChanges());
+		}
+
+		return TPromise.as([]);
 	}
 }
 

src/vs/workbench/parts/scm/electron-browser/dirtydiffDecorator.ts

@@ -775,6 +775,20 @@ export class DirtyDiffController implements IEditorContribution {
 		}
 	}
 
+	getChanges(): IChange[] {
+		if (!this.modelRegistry) {
+			return [];
+		}
+
+		const model = this.modelRegistry.getModel(this.editor.getModel());
+
+		if (!model) {
+			return [];
+		}
+
+		return model.changes;
+	}
+
 	dispose(): void {
 		this.disposables = dispose(this.disposables);
 	}