From 6dcfa8fbfed9c1ff80bd0024e71f766f1f5f6070 Mon Sep 17 00:00:00 2001
From: Johannes Rieken <johannes.rieken@gmail.com>
Date: Tue, 19 Jun 2018 16:13:14 +0200
Subject: [PATCH] add proposed onWillRenameFile event, #43768

---
 src/vs/vscode.proposed.d.ts                   |  7 +++++++
 src/vs/workbench/api/node/extHost.api.impl.ts |  3 +++
 .../api/node/extHostFileSystemEventService.ts | 20 ++++++++++++++++++-
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index 6e4e551b5d9..13c728dda87 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -634,7 +634,14 @@ declare module 'vscode' {
 		readonly newUri: Uri;
 	}
 
+	export interface FileWillRenameEvent {
+		readonly oldUri: Uri;
+		readonly newUri: Uri;
+		waitUntil(thenable: Thenable<any>): void;
+	}
+
 	export namespace workspace {
+		export const onWillRenameFile: Event<FileWillRenameEvent>;
 		export const onDidRenameFile: Event<FileRenameEvent>;
 	}
 	//#endregion
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index 59476e88872..8002c970830 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -578,6 +578,9 @@ export function createApiFactory(
 			}),
 			onDidRenameFile: proposedApiFunction(extension, (listener, thisArg?, disposables?) => {
 				return extHostFileSystemEvent.onDidRenameFile(listener, thisArg, disposables);
+			}),
+			onWillRenameFile: proposedApiFunction(extension, (listener, thisArg?, disposables?) => {
+				return extHostFileSystemEvent.onWillRenameFile(listener, thisArg, disposables);
 			})
 		};
 
diff --git a/src/vs/workbench/api/node/extHostFileSystemEventService.ts b/src/vs/workbench/api/node/extHostFileSystemEventService.ts
index 5fd040d24a6..476a96a3c00 100644
--- a/src/vs/workbench/api/node/extHostFileSystemEventService.ts
+++ b/src/vs/workbench/api/node/extHostFileSystemEventService.ts
@@ -98,8 +98,10 @@ export class ExtHostFileSystemEventService implements ExtHostFileSystemEventServ
 
 	private _onFileEvent = new Emitter<FileSystemEvents>();
 	private _onDidRenameFile = new Emitter<vscode.FileRenameEvent>();
+	private _onWillRenameFile = new Emitter<vscode.FileWillRenameEvent>();
 
 	readonly onDidRenameFile: Event<vscode.FileRenameEvent> = this._onDidRenameFile.event;
+	readonly onWillRenameFile: Event<vscode.FileWillRenameEvent> = this._onWillRenameFile.event;
 
 	constructor() {
 	}
@@ -117,6 +119,22 @@ export class ExtHostFileSystemEventService implements ExtHostFileSystemEventServ
 	}
 
 	$onWillRename(oldUri: UriComponents, newUri: UriComponents): TPromise<any> {
-		return undefined;
+
+		let thenables: Thenable<any>[] = [];
+
+		this._onWillRenameFile.fire({
+			oldUri: URI.revive(oldUri),
+			newUri: URI.revive(newUri),
+			waitUntil(thenable: Thenable<any>): void {
+				if (Object.isFrozen(thenables)) {
+					throw new Error('waitUntil cannot be called async');
+				}
+				thenables.push(thenable.then(undefined, err => console.error(err)));
+			}
+		});
+
+		Object.freeze(thenables);
+
+		return TPromise.join(thenables);
 	}
 }