Auto-generated completion scripts add `NuShell` support

[epage]

Issue by hustcer Monday Sep 20, 2021 at 00:22 GMT Originally opened as https://github.com/clap-rs/clap/issues/2778

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Please complete the following tasks

• [X] I have searched the discussions
• [X] I have searched the existing issues

Clap Version

3.0.0-beta.4

Describe your use case

Auto-generated completion scripts add NuShell support

Describe the solution you'd like

Auto-generated completion scripts add NuShell support, just as clap support (Bash, Zsh, Fish, Elvish and PowerShell), Thx

Alternatives, if applicable

No response

Additional Context

nu --version
───┬────────────────────┬────────────────────────────────────────────────────────────────────────────────────
 # │      Column0       │                                      Column1
───┼────────────────────┼────────────────────────────────────────────────────────────────────────────────────
 0 │ version            │ 0.37.0
 1 │ build_os           │ macos-x86_64
 2 │ rust_version       │ rustc 1.55.0
 3 │ cargo_version      │ cargo 1.55.0
 4 │ pkg_version        │ 0.37.0
 5 │ build_time         │ 2021-09-14 19:45:30 +00:00
 6 │ build_rust_channel │ release
 7 │ features           │ clipboard-cli, ctrlc, dataframe, default, rustyline, term, trash, uuid, which, zip
 8 │ installed_plugins  │
───┴────────────────────┴────────────────────────────────────────────────────────────────────────────────────

[epage]

Comment by epage Monday Sep 20, 2021 at 17:01 GMT

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Somewhat unrelated but I wonder what the code size / compile time looks like for all of our generators and if there is anything we can help developers with development time as our generators expand in number of targets and capabilities.

[epage]

Comment by pksunkara Monday Sep 20, 2021 at 21:09 GMT

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That was the intention for extra generators. For the basic common ones, we have them in the package itself, but if we were to implement this, we would create a new package called clap_generator_nushell or something.

One thing I am not sure if we can do in Rust because of these new const stuff is, can a user extend the Shell enum through 3rd party code (traits)?

[epage]

Comment by epage Monday Sep 20, 2021 at 21:27 GMT

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A user could manually impl ArgEnum and flatten Shell into their enum or we could add flatten support but I'm not aware of a language feature that would help.