sync wordwrap transient state to input1/2 editors (microsoft#158484)

fixes microsoft#155280

Author: jrieken

src/vs/workbench/contrib/mergeEditor/browser/view/mergeEditor.ts

@@ -39,6 +39,7 @@ import { AbstractTextEditor } from 'vs/workbench/browser/parts/editor/textEditor
 import { DEFAULT_EDITOR_ASSOCIATION, EditorInputWithOptions, IEditorOpenContext, IResourceMergeEditorInput } from 'vs/workbench/common/editor';
 import { EditorInput } from 'vs/workbench/common/editor/editorInput';
 import { applyTextEditorOptions } from 'vs/workbench/common/editor/editorOptions';
+import { readTransientState, writeTransientState } from 'vs/workbench/contrib/codeEditor/browser/toggleWordWrap';
 import { MergeEditorInput } from 'vs/workbench/contrib/mergeEditor/browser/mergeEditorInput';
 import { DocumentMapping, getOppositeDirection, MappingDirection } from 'vs/workbench/contrib/mergeEditor/browser/model/mapping';
 import { MergeEditorModel } from 'vs/workbench/contrib/mergeEditor/browser/model/mergeEditorModel';
@@ -117,6 +118,7 @@ export class MergeEditor extends AbstractTextEditor<IMergeEditorViewState> {
 		@IEditorService editorService: IEditorService,
 		@IEditorGroupsService editorGroupService: IEditorGroupsService,
 		@IFileService fileService: IFileService,
+		@ICodeEditorService private readonly _codeEditorService: ICodeEditorService,
 	) {
 		super(MergeEditor.ID, telemetryService, instantiation, storageService, textResourceConfigurationService, themeService, editorService, editorGroupService, fileService);
 
@@ -177,7 +179,6 @@ export class MergeEditor extends AbstractTextEditor<IMergeEditorViewState> {
 			)
 		);
 
-
 		// TODO@jrieken make this proper: add menu id and allow extensions to contribute
 		const toolbarMenu = this._menuService.createMenu(MenuId.MergeToolbar, this._contextKeyService);
 		const toolbarMenuDisposables = new DisposableStore();
@@ -377,6 +378,19 @@ export class MergeEditor extends AbstractTextEditor<IMergeEditorViewState> {
 			});
 		}, 'update alignment view zones'));
 
+		// word wrap special case - sync transient state from result model to input[1|2] models
+		const mirrorWordWrapTransientState = () => {
+			const state = readTransientState(model.resultTextModel, this._codeEditorService);
+			writeTransientState(model.input2.textModel, state, this._codeEditorService);
+			writeTransientState(model.input1.textModel, state, this._codeEditorService);
+		};
+		this._sessionDisposables.add(this._codeEditorService.onDidChangeTransientModelProperty(candidate => {
+			if (candidate === this.inputResultView.editor.getModel()) {
+				mirrorWordWrapTransientState();
+			}
+		}));
+		mirrorWordWrapTransientState();
+
 
 		// detect when base, input1, and input2 become empty and replace THIS editor with its result editor
 		// TODO@jrieken@hediet this needs a better/cleaner solution