extensions/typescript-language-features/src/utils/pluginPathsProvider.ts/TypeScriptPluginPathsProvider/resolvePluginPath
class TypeScriptPluginPathsProvider:	private resolvePluginPath(pluginPath: string): string[] {
		if (path.isAbsolute(pluginPath)) {
			return [pluginPath];
		}

		const workspacePath = RelativeWorkspacePathResolver.asAbsoluteWorkspacePath(pluginPath);
		if (workspacePath !== undefined) {
			return [workspacePath];
		}

		return (vscode.workspace.workspaceFolders || [])
			.map(workspaceFolder => path.join(workspaceFolder.uri.fsPath, pluginPath));
	}