nushell/crates
Leon 774769a7ad
color_config now accepts closures as color values (#7141)
# Description

Closes #6909. You can now add closures to your `color_config` themes.
Whenever a value would be printed with `table`, the closure is run with
the value piped-in. The closure must return either a {fg,bg,attr} record
or a color name (`'light_red'` etc.). This returned style is used to
colour the value.

This is entirely backwards-compatible with existing config.nu files.

Example code excerpt:
```
let my_theme = {
    header: green_bold
    bool: { if $in { 'light_cyan' } else { 'light_red' } }
    int: purple_bold
    filesize: { |e| if $e == 0b { 'gray' } else if $e < 1mb { 'purple_bold' } else { 'cyan_bold' } }
    duration: purple_bold
    date: { (date now) - $in | if $in > 1wk { 'cyan_bold' } else if $in > 1day { 'green_bold' } else { 'yellow_bold' } }
    range: yellow_bold
    string: { if $in =~ '^#\w{6}$' { $in } else { 'white' } }
    nothing: white
```
Example output with this in effect:
![2022-11-16 12 47 23 AM - style_computer
rs_-_nushell_-_VSCodium](https://user-images.githubusercontent.com/83939/201952558-482de05d-69c7-4bf2-91fc-d0964bf71264.png)
![2022-11-16 12 39 41 AM - style_computer
rs_-_nushell_-_VSCodium](https://user-images.githubusercontent.com/83939/201952580-2384bb86-b680-40fe-8192-71bae396c738.png)
![2022-11-15 09 21 54 PM - run_external
rs_-_nushell_-_VSCodium](https://user-images.githubusercontent.com/83939/201952601-343fc15d-e4a8-4a92-ad89-9a7d17d42748.png)

Slightly important notes:

* Some color_config names, namely "separator", "empty" and "hints", pipe
in `null` instead of a value.
* Currently, doing anything non-trivial inside a closure has an
understandably big perf hit. I currently do not actually recommend
something like `string: { if $in =~ '^#\w{6}$' { $in } else { 'white' }
}` for serious work, mainly because of the abundance of string-type data
in the world. Nevertheless, lesser-used types like "date" and "duration"
work well with this.
* I had to do some reorganisation in order to make it possible to call
`eval_block()` that late in table rendering. I invented a new struct
called "StyleComputer" which holds the engine_state and stack of the
initial `table` command (implicit or explicit).
* StyleComputer has a `compute()` method which takes a color_config name
and a nu value, and always returns the correct Style, so you don't have
to worry about A) the color_config value was set at all, B) whether it
was set to a closure or not, or C) which default style to use in those
cases.
* Currently, errors encountered during execution of the closures are
thrown in the garbage. Any other ideas are welcome. (Nonetheless, errors
result in a huge perf hit when they are encountered. I think what should
be done is to assume something terrible happened to the user's config
and invalidate the StyleComputer for that `table` run, thus causing
subsequent output to just be Style::default().)
* More thorough tests are forthcoming - ran into some difficulty using
`nu!` to take an alternative config, and for some reason `let-env config
=` statements don't seem to work inside `nu!` pipelines(???)
* The default config.nu has not been updated to make use of this yet. Do
tell if you think I should incorporate that into this.

# User-Facing Changes

See above.

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace --features=extra -- -D warnings -D
clippy::unwrap_used -A clippy::needless_collect` to check that you're
using the standard code style
- `cargo test --workspace --features=extra` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
2022-12-17 07:07:56 -06:00
..
nu_plugin_custom_values bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu_plugin_example Reduced LOC by replacing several instances of Value::Int {}, Value::Float{}, Value::Bool {}, and Value::String {} with Value::int(), Value::float(), Value::boolean() and Value::string() (#7412) 2022-12-09 11:37:51 -05:00
nu_plugin_gstat Reduced LOC by replacing several instances of Value::Int {}, Value::Float{}, Value::Bool {}, and Value::String {} with Value::int(), Value::float(), Value::boolean() and Value::string() (#7412) 2022-12-09 11:37:51 -05:00
nu_plugin_inc Reduced LOC by replacing several instances of Value::Int {}, Value::Float{}, Value::Bool {}, and Value::String {} with Value::int(), Value::float(), Value::boolean() and Value::string() (#7412) 2022-12-09 11:37:51 -05:00
nu_plugin_python (nu_plugin_python): Send back the signature required fields. (#7489) 2022-12-15 14:37:12 -06:00
nu_plugin_query bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-cli color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-color-config color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-command color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-engine Add helper method to check whether ctrl+c was pressed, adopt it (#7482) 2022-12-15 09:39:24 -08:00
nu-explore color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-glob bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-json bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-parser Fix for escaping backslashes in interpolated strings (fixes #6737) (#7119) 2022-12-14 07:54:13 -06:00
nu-path bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-plugin bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-pretty-hex bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-protocol color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-system bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-table color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
nu-term-grid bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
nu-test-support Use nu-path correctly in nu! test macro to make dev-dependency transitive (#7488) 2022-12-15 18:53:26 +01:00
nu-utils color_config now accepts closures as color values (#7141) 2022-12-17 07:07:56 -06:00
old bump to dev build v0.72.2 (#7360) 2022-12-05 14:18:06 -06:00
README.md Remove old nushell/merge engine-q 2022-02-07 14:54:06 -05:00

Nushell core libraries and plugins

These sub-crates form both the foundation for Nu and a set of plugins which extend Nu with additional functionality.

Foundational libraries are split into two kinds of crates:

  • Core crates - those crates that work together to build the Nushell language engine
  • Support crates - a set of crates that support the engine with additional features like JSON support, ANSI support, and more.

Plugins are likewise also split into two types:

  • Core plugins - plugins that provide part of the default experience of Nu, including access to the system properties, processes, and web-connectivity features.
  • Extra plugins - these plugins run a wide range of different capabilities like working with different file types, charting, viewing binary data, and more.