src/vs/workbench/contrib/files/common/explorerFileNestingTrie.ts/ExplorerFileNestingTrie/getAttributes
class ExplorerFileNestingTrie:	private getAttributes(filename: string, dirname: string): FilenameAttributes {
		const lastDot = filename.lastIndexOf('.');
		if (lastDot < 1) {
			return {
				dirname,
				basename: filename,
				extname: ''
			};
		} else {
			return {
				dirname,
				basename: filename.substring(0, lastDot),
				extname: filename.substring(lastDot + 1)
			};
		}
	}