private _transformIncoming(extension: ILocalExtension, uriTransformer: IURITransformer): ILocalExtension {
		return extension ? { ...extension, ...{ location: URI.revive(uriTransformer.transformIncoming(extension.location)) } } : extension;
	}

function transformOutgoingURI(uri: URI, transformer: IURITransformer | null): URI {
	return transformer ? transformer.transformOutgoingURI(uri) : uri;
}

function transformIncomingURI(uri: UriComponents, transformer: IURITransformer | null): URI {
	return URI.revive(transformer ? transformer.transformIncoming(uri) : uri);
}

	download(from: URI, to: string): TPromise<void> {
		from = this.uriTransformer.transformOutgoing(from);
		const dirName = path.dirname(to);
		let out: fs.WriteStream;
		return new TPromise((c, e) => {
			return mkdirp(dirName)
				.then(() => {
					out = fs.createWriteStream(to);
					out.once('close', () => c(null));
					out.once('error', e);
					const uploadStream = this.channel.listen('upload', from);
					const disposable = uploadStream((result: UploadResponse) => {
						if (result === void 0) {
							out.end();
							disposable.dispose();
							c(null);
						} else if (Buffer.isBuffer(result)) {
							out.write(result);
						} else if (typeof result === 'string') {
							out.close();
							disposable.dispose();
							e(result);
						}
					});
				});
		});
	}

	install(vsix: URI): Promise<IExtensionIdentifier> {
		return Promise.resolve(this.channel.call('install', [this.uriTransformer.transformOutgoing(vsix)]));
	}

	private _transformOutgoing(extension: ILocalExtension | undefined): ILocalExtension | undefined {
		return extension ? { ...extension, ...{ location: this.uriTransformer.transformOutgoing(extension.location) } } : extension;
	}

	private _transformIncoming(extension: ILocalExtension | undefined): ILocalExtension | undefined {
		return extension ? { ...extension, ...{ location: URI.revive(this.uriTransformer.transformIncoming(extension.location)) } } : extension;
	}

	return transformer ? cloneAndChange(extension, value => value instanceof URI ? transformer.transformOutgoingURI(value) : undefined) : extension;