mirror of
https://github.com/nushell/nushell.git
synced 2024-12-25 08:29:07 +01:00
ed8dee04b6
# Description
just caught a last mention to `let-env` in the `CONTRIBUTING.md`
document 😋
# User-Facing Changes
# Tests + Formatting
# After Submitting
249 lines
11 KiB
Markdown
249 lines
11 KiB
Markdown
# Contributing
|
|
|
|
Welcome to the Nushell standard library and thank you for considering
|
|
contributing!
|
|
|
|
## Ideas for the standard library
|
|
If you've got a great idea, or just want to contribute to open source by
|
|
working on the Nushell standard library, we invite you to talk to the team
|
|
before you start coding. You'll find we're friendly, passionate about Nushell
|
|
and always open to new ideas!
|
|
|
|
You'll generally find the team members on
|
|
[Discord `#standard-library` channel][discord#standard-library] and can have
|
|
preliminary discussions there to clarify the issues involved.
|
|
|
|
You can open a [Github issue][new-issue] to have a more focused discussion of
|
|
your idea.
|
|
|
|
Generally, we think the standard library should contain items that are relevant
|
|
to most/all Nushell users regardless of the application space they're working
|
|
in. If your idea isn't quite so broadly applicable, consider publishing it in
|
|
[`nu_scripts`].
|
|
|
|
Preliminary discussions should focus on the *user benefit* your idea would
|
|
provide.
|
|
|
|
How many users will be affected by your idea, how much would it help them solve
|
|
a problem or work more productively? Given consensus on the user benefit, the
|
|
team will be motivated to help you create, deploy and maintain a solution long
|
|
term.
|
|
|
|
## Lifecycle of a change
|
|
1. Verify the team thinks your idea is potentially relevant and useful, as
|
|
above.
|
|
1. If it's more than a simple bug fix, open a placeholder PR as soon as you get
|
|
started and [set it to draft status][github_draft_pr].
|
|
This will alert other contributors that you're working in this area and let
|
|
you advertise roughly what scope of changes you're thinking of. See
|
|
[below](#the-pr) for details.
|
|
1. Get things working in your local development environment.
|
|
If you have questions along the way, you can post a question in your PR or
|
|
have a more casual discussion with Nushell fans on
|
|
[Discord `#implementation-chat` channel][discord#implementation-chat].
|
|
1. When you get to an appropriate state of doneness, push your changes to the
|
|
PR and remove the draft status.
|
|
1. Team members and other contributors will then review your PR.
|
|
Respond to any review comments they raise and address them one way or
|
|
another. (Not all comments demand you make a change!)
|
|
1. When you and the team are comfortable with the PR, a team member will merge
|
|
it into the repo and you can delete your working branch.
|
|
1. If you've added a whole new command or made a breaking change,
|
|
(strongly) consider writing it up for the release notes.
|
|
Currently, release notes are maintained in a different repo,
|
|
[`nushell.github.io`]. Make your change in a local clone of that repo and
|
|
submit a PR to the release notes repo to get it integrated.
|
|
|
|
## Developing
|
|
(All paths below shown relative to the root folder of the git repository
|
|
containing the standard library.)
|
|
|
|
### Setup
|
|
0. Install the Rust toolchain and Nushell build tools.
|
|
See [`nushell`'s `CONTRIBUTING.md`][`CONTRIBUTING.md`] for details. The
|
|
standard library is tightly coupled to a particular version of Nushell
|
|
interpreter, you need to be running that version to test your changes (unlike
|
|
a "normal" script module library).
|
|
1. Clone the Nushell repo containing the standard library and create a feature
|
|
branch for your development work.
|
|
Currently, that's the [Nushell interpreter source repo][`nushell`].
|
|
Once you set your working directory to the root of this repository, you'll
|
|
generally leave it there throughout the session.
|
|
```shell
|
|
git clone https://github.com/nushell/nushell
|
|
cd nushell
|
|
git checkout -b <featureBranch>
|
|
```
|
|
1. In your IDE, open the folder within the repository containing the standard
|
|
library. The folder is currently `./crates/nu-std`, and it is a Rust crate,
|
|
containing a `Cargo.toml` and subfolders:
|
|
* `src/` (which contains the Rust code to load the standard library modules
|
|
into memory for efficiency),
|
|
* `lib` (which contains all the script module sources for the standard
|
|
library),
|
|
* `tests/` (unit tests for lib).
|
|
|
|
### The PR
|
|
Assuming you've already validated the need with other Nushell contributors,
|
|
you're focusing on design and implementation at this point. Share your thinking
|
|
all along the way!
|
|
|
|
You can open a [draft][github_draft_pr] pull request based on a small,
|
|
placeholder code change and use the PR comments to outline your design and user
|
|
interface. You'll get feedback from other contributors that may lead to a more
|
|
robust and perhaps more idomatic solution. The threads in the PR can be a
|
|
convenient reference for you when writing release notes and for others on the
|
|
team when researching issues.
|
|
|
|
> **Note**
|
|
> the PR will not get final code review or be merged until you remove the draft
|
|
> status.
|
|
|
|
### Design considerations
|
|
The standard library consists of Nushell custom commands and their associated
|
|
environment variables, packaged in script modules underneath module `std`. For
|
|
background on scripts, custom commands and modules, see the
|
|
[Modules chapter of the Nushell book][book@modules].
|
|
|
|
To add a completely new module, for example, a `foo` command and some
|
|
`foo subcommand`s, you will be dealing with 2 new source files: the module
|
|
source itself (`./crates/nu-std/lib/foo.nu`) and a unit tests file
|
|
(`./crates/nu-std/tests/test_foo`); and will be modifying 1 or 2 existing files
|
|
(`./crates/nu-std/lib/mod.nu` and possibly `./crates/nu-std/src/lib.rs`). This
|
|
is described below:
|
|
|
|
1. Source for a custom command `foo` should go in `./crates/nu-std/lib/foo.nu`.
|
|
* A source file will typically implement multiple subcommands and possibly
|
|
a main command as well.
|
|
Use `export def` to make these names public to your users.
|
|
* If your command is updating environment variables, you must use
|
|
`export def --env` (instead of `export def`) to define the subcommand,
|
|
`export-env {}` to initialize the environment variables and `$env.VAR = val` to
|
|
update them. For an example of a custom command which modifies
|
|
environment variables, see: `./crates/nu-std/lib/dirs.nu`.
|
|
For an example of a custom command which does *not* modify environment
|
|
variables, see: `./crates/nu-std/lib/assert.nu`.
|
|
* If your standard library module wishes to use a utility from another
|
|
module of the standard library, for example `log info`, you need to
|
|
import it directly from its module in the `use` statement.
|
|
```nushell
|
|
... your foo.nu ...
|
|
export def mycommand [] {
|
|
use log "log info"
|
|
. . .
|
|
log info "info level log message"
|
|
. . .
|
|
}
|
|
```
|
|
This is `use log "log info"` rather than `use std "log info"` (which is
|
|
the usual way commands are imported from the standard library) because
|
|
your `foo` module is also a child module under `std`.
|
|
1. Unit tests for `foo` should go in `./crates/nu-std/tests/test_foo.nu`. Thou
|
|
shalt provide unit tests to cover your changes.
|
|
* Unit tests should use one of the `assert` commands to check a condition
|
|
and report the failure in a standard format.
|
|
* To import `assert` commands for use in your test, import them via
|
|
`use std` (unlike the `use log` for your source code; the tests are not
|
|
modules under `std`). For example:
|
|
```nushell
|
|
... your test_foo.nu ...
|
|
def test1 [] {
|
|
use std
|
|
. . .
|
|
std assert greater $l $r
|
|
. . .
|
|
std assert $predicate
|
|
}
|
|
|
|
def test2 [] {
|
|
use std ['assert greater' assert]
|
|
. . .
|
|
assert greater $l $r
|
|
. . .
|
|
assert $predicate
|
|
}
|
|
```
|
|
The choice of import style is up to you.
|
|
1. A `foo` command will be exposed to the user as `std foo` (at a minimum).
|
|
To enable this, update file `./crates/nu-std/lib/mod.nu` and add this code:
|
|
```nushell
|
|
export use foo * # command doesn't update environment
|
|
export-env {
|
|
use bar * # command *does* update environment
|
|
}
|
|
```
|
|
The `use *` hoists the public definitions in `foo.nu` into `mod.nu` and
|
|
thus into the `std` namespace.
|
|
1. Some commands from the standard library are also preloaded, so user can
|
|
invoke them without explicit import via `use std ...`.
|
|
A command implemented as `std foo`, can be preloaded as a bare `foo`:
|
|
* modify `./crates/nu-std/src/lib.rs`,
|
|
* find the initialization of the "prelude" at line 90 or thereabouts
|
|
* add `("foo", "foo")`
|
|
* or, to be preloaded as `std foo`, add `("std foo", "foo")`.
|
|
|
|
(This code may be restructured soon: if you can't find it, check with the
|
|
team on Discord.)
|
|
> **Note**
|
|
> that you will need to recompile the Nushell interpreter to test this
|
|
> change, see the ["setup" section][`CONTRIBUTING.md`#setup] of Nushell's
|
|
> `CONTRIBUTING.md`.
|
|
|
|
More design guidelines:
|
|
|
|
1. Ensure your custom command provides useful help.
|
|
This is done with comments before the `def` for the custom command.
|
|
1. Use `error make` to report can't-proceed errors to user, not `log error`.
|
|
1. Use `log info` to provide verbose progress messages that the user can
|
|
optionally enable for troubleshooting. e.g:
|
|
```nushell
|
|
NU_LOG_LEVEL=INFO foo # verbose messages from command foo
|
|
```
|
|
1. Use `assert` in unit tests to check for and report failures.
|
|
|
|
### Useful Commands
|
|
- Run all unit tests for the standard library:
|
|
```nushell
|
|
cargo run -- -c 'use std testing; testing run-tests --path crates/nu-std'
|
|
```
|
|
> **Note**
|
|
> this uses the debug version of NU interpreter from the same repo, which is
|
|
> the usual development scenario.
|
|
> Log level 'ERROR' shows only failures (meaning no output is the desired
|
|
> outcome).
|
|
> Log level 'INFO' shows progress by module and 'DEBUG' show each individual
|
|
> test.
|
|
- Run all tests for a specific test module, e.g,
|
|
`crates/nu-std/tests/test_foo.nu`
|
|
```nushell
|
|
cargo run -- -c 'use std testing; testing run-tests --path crates/nu-std --module test_foo'
|
|
```
|
|
- Run a custom command with additional logging (assuming you have instrumented
|
|
the command with `log <level>`, as we recommend.)
|
|
```nushell
|
|
NU_LOG_LEVEL=INFO std foo bar bas # verbose
|
|
NU_LOG_LEVEL=DEBUG std foo bar bas # very verbose
|
|
```
|
|
- Build and run Nushell (e.g, if you modify the prelude):
|
|
```nushell
|
|
cargo run
|
|
```
|
|
|
|
## Git commit and repo conventions
|
|
The standard library project uses the same protocols and conventions
|
|
for squashing git commits and handling github PRs as the core Nushell project.
|
|
Please see the ["Git etiquette" section][`CONTRIBUTING.md`#git-etiquette] of
|
|
Nushell's `CONTRIBUTING.md` for details.
|
|
|
|
[github_draft_pr]: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/changing-the-stage-of-a-pull-request
|
|
[discord#standard-library]: https://discord.com/channels/601130461678272522/1075541668922658868
|
|
[discord#implementation-chat]: https://discord.com/channels/601130461678272522/615962413203718156
|
|
[new-issue]: https://github.com/nushell/nushell/issues/new/choose
|
|
[`nushell`]: https://github.com/nushell/nushell
|
|
[`nu_scripts`]: https://github.com/nushell/nu_scripts
|
|
[`nushell.github.io`]: https://github.com/nushell/nushell.github.io
|
|
[`CONTRIBUTING.md`]: https://github.com/nushell/nushell/blob/main/CONTRIBUTING.md
|
|
[`CONTRIBUTING.md`#setup]: https://github.com/nushell/nushell/blob/main/CONTRIBUTING.md#setup
|
|
[`CONTRIBUTING.md`#git-etiquette]: https://github.com/nushell/nushell/blob/main/CONTRIBUTING.md#git-etiquette
|
|
[book@modules]: https://www.nushell.sh/book/modules.html
|