nushell/crates/nu-cmd-extra
Piepmatz 3d5f853b03
Start to Add WASM Support Again (#14418)
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# Description
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The [nushell/demo](https://github.com/nushell/demo) project successfully
demonstrated running Nushell in the browser using WASM. However, the
current version of Nushell cannot be easily built for the
`wasm32-unknown-unknown` target, the default for `wasm-bindgen`.

This PR introduces initial support for the `wasm32-unknown-unknown`
target by disabling OS-dependent features such as filesystem access, IO,
and platform/system-specific functionality. This separation is achieved
using a new `os` feature in the following crates:

 - `nu-cmd-lang`
 - `nu-command`
 - `nu-engine`
 - `nu-protocol`

The `os` feature includes all functionality that interacts with an
operating system. It is enabled by default, but can be disabled using
`--no-default-features`. All crates that depend on these core crates now
use `--no-default-features` to allow compilation for WASM.

To demonstrate compatibility, the following script builds all crates
expected to work with WASM. Direct user interaction, running external
commands, working with plugins, and features requiring `openssl` are out
of scope for now due to their complexity or reliance on C libraries,
which are difficult to compile and link in a WASM environment.

```nushell
[ # compatible crates
	"nu-cmd-base",
	"nu-cmd-extra",
	"nu-cmd-lang",
	"nu-color-config",
	"nu-command",
	"nu-derive-value",
	"nu-engine",
	"nu-glob",
	"nu-json",
	"nu-parser",
	"nu-path",
	"nu-pretty-hex",
	"nu-protocol",
	"nu-std",
	"nu-system",
	"nu-table",
	"nu-term-grid",
	"nu-utils",
	"nuon"
] | each {cargo build -p $in --target wasm32-unknown-unknown --no-default-features}
```

## Caveats
This PR has a few caveats:
1. **`miette` and `terminal-size` Dependency Issue**
`miette` depends on `terminal-size`, which uses `rustix` when the target
is not Windows. However, `rustix` requires `std::os::unix`, which is
unavailable in WASM. To address this, I opened a
[PR](https://github.com/eminence/terminal-size/pull/68) for
`terminal-size` to conditionally compile `rustix` only when the target
is Unix. For now, the `Cargo.toml` includes patches to:
    - Use my forked version of `terminal-size`.
- ~~Use an unreleased version of `miette` that depends on
`terminal-size@0.4`.~~

These patches are temporary and can be removed once the upstream changes
are merged and released.

2. **Test Output Adjustments**
Due to the slight bump in the `miette` version, one test required
adjustments to accommodate minor formatting changes in the error output,
such as shifted newlines.

# User-Facing Changes
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helps us keep track of breaking changes. -->
This shouldn't break anything but allows using some crates for targeting
`wasm32-unknown-unknown` to revive the demo page eventually.

# Tests + Formatting
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> ```
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- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

I did not add any extra tests, I just checked that compiling works, also
when using the host target but unselecting the `os` feature.

# After Submitting
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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.
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~~Breaking the wasm support can be easily done by adding some `use`s or
by adding a new dependency, we should definitely add some CI that also
at least builds against wasm to make sure that building for it keep
working.~~
I added a job to build wasm.

---------

Co-authored-by: Ian Manske <ian.manske@pm.me>
2024-11-30 07:57:11 -06:00
..
assets REFACTOR: move the 0% commands to nu-cmd-extra (#9404) 2023-07-06 08:31:31 -07:00
src Add Filesize type (#14369) 2024-11-29 21:24:17 +00:00
tests Make into bits produce bitstring stream (#13310) 2024-07-07 08:00:57 -05:00
Cargo.toml Start to Add WASM Support Again (#14418) 2024-11-30 07:57:11 -06:00
LICENSE nu-cmd-extra crate infrastructure in place with the Bits command as the model for adding other commands (#9327) 2023-06-01 10:46:16 -07:00
README.md Remove feat extra and include in default (#12140) 2024-03-10 17:29:02 +01:00

nu-cmd-extra

The commands in this crate are the extra commands of Nushell. These commands are not in a state to be guaranteed to be part of the 1.0 API; meaning that there is no guarantee longer term that these commands will be around into the future.

For a while we did exclude them behind the --features extra compile time flag, meaning that the default release did not contain them. As we (the Nushell team) shipped a full build including both extra and dataframe for some time, we chose to sunset the extra feature but keep the commands in this crate for now. In the future the commands may be moved to more topical crates or discarded into plugins.