split_once() t 0x5634d1e02050 0x5634d1e02038 .f 80000000 .split_once() .result = foo bar .BufLineReader 1 [foo ] 2 [bar ] 3 [leftover] 4 [] 5 [] .stdout isatty() = 0 stdin isatty() = 0 files_test Oils Source Code ================ [![Build Status](https://github.com/oils-for-unix/oils/actions/workflows/all-builds.yml/badge.svg)](https://github.com/oils-for-unix/oils/actions/workflows/all-builds.yml) files_test DONE stdout..c = h c = i . Total: 8 tests (270 ticks, 0.000 sec), 27 assertions Pass: 8, fail: 0, skip: 0.