# 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:
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.
I've been working on streaming and pipeline interruption lately. It was
bothering me that checking ctrl+c (something we want to do often) always
requires a bunch of boilerplate like:
```rust
use std::sync::atomic::Ordering;
if let Some(ctrlc) = &engine_state.ctrlc {
if ctrlc.load(Ordering::SeqCst) {
...
```
I added a helper method to cut that down to:
```rust
if nu_utils::ctrl_c::was_pressed(&engine_state.ctrlc) {
...
```
Allows use of slightly optimized variants that check if they have to use
the heavier vte parser. Tries to avoid unnnecessary allocations. Initial
performance characteristics proven out in #4378.
Also reduces boilerplate with right-ward drift.
* Add decimals to int when using `into string --decimals`
* Add tests for `into string` when converting int with `--decimals`
* Apply formatting
* Merge `into_str` test files
* Comment out unused code and add TODOs
* Use decimal separator depending on system locale
* Add test helper to run closure in different locale
* Add tests for int-to-string conversion using different locales
* Add utils function to get system locale
* Add panic message when locking mutex fails
* Catch and resume panic later to prevent Mutex poisoning when test fails
* Move test to `nu-test-support` to keep `nu-utils` free of `nu-*` dependencies
See https://github.com/nushell/nushell/pull/6085#issuecomment-1193131694
* Rename test support fn `with_fake_locale` to `with_locale_override`
* Move `get_system_locale()` to `locale` module
* Allow overriding locale with special env variable (when not in release)
* Use special env var to override locale during testing
* Allow callback to return a value in `with_locale_override()`
* Allow multiple options in `nu!` macro
* Allow to set locale as `nu!` macro option
* Use new `locale` option of `nu!` macro instead of `with_locale_override`
Using the `locale` options does not lock the `LOCALE_OVERRIDE_MUTEX`
mutex in `nu-test-support::locale_override` but instead calls the `nu`
command directly with the `NU_LOCALE_OVERRIDE` environment variable.
This allows for parallel test excecution.
* Fix: Add option identifier for `cwd` in usage of `nu!` macro
* Rely on `Display` trait for formatting `nu!` macro command
- Removed the `DisplayPath` trait
- Implement `Display` for `AbsolutePath`, `RelativePath` and
`AbsoluteFile`
* Default to locale `en_US.UTF-8` for tests when using `nu!` macro
* Add doc comment to `nu!` macro
* Format code using `cargo fmt --all`
* Pass function directly instead of wrapping the call in a closure
https://rust-lang.github.io/rust-clippy/master/index.html#redundant_closure
* Pass function to `or_else()` instead of calling it inside `or()`
https://rust-lang.github.io/rust-clippy/master/index.html#or_fun_call
* Fix: Add option identifier for `cwd` in usage of `nu!` macro
