nushell/crates/nu-command/tests
Devyn Cairns e69a02d379
Add tee command for operating on copies of streams (#11928)
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# Description
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This is inspired by the Unix tee command, but significantly more
powerful. Rather than just writing to a file, you can do any kind of
stream operation that Nushell supports within the closure.

The equivalent of Unix `tee -a file.txt` would be, for example, `command
| tee { save -a file.txt }` - but of course this is Nushell, and you can
do the same with structured data to JSON objects, or even just run any
other command on the system with it.

A `--stderr` flag is provided for operating on the stderr stream from
external programs. This may produce unexpected results if the stderr
stream is not then also printed by something else - nushell currently
doesn't. See #11929 for the fix for that.

# User-Facing Changes
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If someone was using the system `tee` command, they might be surprised
to find that it's different.

# Tests + Formatting
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crates/nu-std"` to run the tests for the standard library

> **Note**
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- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`


# After Submitting
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2024-02-28 17:08:31 -06:00
..
commands Add tee command for operating on copies of streams (#11928) 2024-02-28 17:08:31 -06:00
format_conversions Add date support in from xlsx (#11952) 2024-02-24 07:25:51 -06:00
main.rs Enforce required, optional, and rest positional arguments start with an uppercase and end with a period. (#11285) 2023-12-15 14:32:37 +08:00