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https://github.com/rust-lang/rust-clippy
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d647696c1f
So, some context for this, well, more a story. I'm not used to scripting, I've never really scripted anything, even if it's a valuable skill. I just never really needed it. Now, `@flip1995` correctly suggested using a script for this in `rust-clippy#7813`...
And I decided to write a script using nushell because why not? This was a mistake... I spend way more time on this than I would like to admit. It has definitely been more than 4 hours. It shouldn't take that long, but me being new to scripting and nushell just wasn't a good mixture... Anyway, here is the script that creates another script which adds the versions. Fun...
Just execute this on the `gh-pages` branch and the resulting `replacer.sh` in `clippy_lints` and it should all work.
```nu
mv v0.0.212 rust-1.00.0;
mv beta rust-1.57.0;
mv master rust-1.58.0;
let paths = (open ./rust-1.58.0/lints.json | select id id_span | flatten | select id path);
let versions = (
ls | where name =~ "rust-" | select name | format {name}/lints.json |
each { open $it | select id | insert version $it | str substring "5,11" version} |
group-by id | rotate counter-clockwise id version |
update version {get version | first 1} | flatten | select id version);
$paths | each { |row|
let version = ($versions | where id == ($row.id) | format {version})
let idu = ($row.id | str upcase)
$"sed -i '0,/($idu),/{s/pub ($idu),/#[clippy::version = "($version)"]\n pub ($idu),/}' ($row.path)"
} | str collect ";" | str find-replace --all '1.00.0' 'pre 1.29.0' | save "replacer.sh";
```
And this still has some problems, but at this point I just want to be done -.-
68 lines
2.2 KiB
Rust
68 lines
2.2 KiB
Rust
//! lint when there is an enum with no variants
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use clippy_utils::diagnostics::span_lint_and_help;
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use rustc_hir::{Item, ItemKind};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_session::{declare_lint_pass, declare_tool_lint};
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declare_clippy_lint! {
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/// ### What it does
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/// Checks for `enum`s with no variants.
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///
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/// As of this writing, the `never_type` is still a
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/// nightly-only experimental API. Therefore, this lint is only triggered
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/// if the `never_type` is enabled.
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///
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/// ### Why is this bad?
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/// If you want to introduce a type which
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/// can't be instantiated, you should use `!` (the primitive type "never"),
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/// or a wrapper around it, because `!` has more extensive
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/// compiler support (type inference, etc...) and wrappers
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/// around it are the conventional way to define an uninhabited type.
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/// For further information visit [never type documentation](https://doc.rust-lang.org/std/primitive.never.html)
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///
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///
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/// ### Example
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/// Bad:
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/// ```rust
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/// enum Test {}
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/// ```
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///
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/// Good:
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/// ```rust
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/// #![feature(never_type)]
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///
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/// struct Test(!);
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/// ```
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#[clippy::version = "pre 1.29.0"]
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pub EMPTY_ENUM,
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pedantic,
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"enum with no variants"
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}
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declare_lint_pass!(EmptyEnum => [EMPTY_ENUM]);
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impl<'tcx> LateLintPass<'tcx> for EmptyEnum {
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fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
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// Only suggest the `never_type` if the feature is enabled
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if !cx.tcx.features().never_type {
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return;
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}
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if let ItemKind::Enum(..) = item.kind {
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let ty = cx.tcx.type_of(item.def_id);
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let adt = ty.ty_adt_def().expect("already checked whether this is an enum");
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if adt.variants.is_empty() {
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span_lint_and_help(
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cx,
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EMPTY_ENUM,
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item.span,
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"enum with no variants",
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None,
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"consider using the uninhabited type `!` (never type) or a wrapper \
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around it to introduce a type which can't be instantiated",
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);
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}
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}
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}
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}
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