80 lines
2.8 KiB
Rust
80 lines
2.8 KiB
Rust
use ast::AttrStyle;
|
|
use clippy_utils::diagnostics::span_lint_and_sugg;
|
|
use rustc_ast as ast;
|
|
use rustc_errors::Applicability;
|
|
use rustc_lint::{LateContext, LateLintPass};
|
|
use rustc_session::{declare_lint_pass, declare_tool_lint};
|
|
|
|
declare_clippy_lint! {
|
|
/// Detects uses of the `#[allow]` attribute and suggests replacing it with
|
|
/// the `#[expect]` (See [RFC 2383](https://rust-lang.github.io/rfcs/2383-lint-reasons.html))
|
|
///
|
|
/// The expect attribute is still unstable and requires the `lint_reasons`
|
|
/// on nightly. It can be enabled by adding `#![feature(lint_reasons)]` to
|
|
/// the crate root.
|
|
///
|
|
/// This lint only warns outer attributes (`#[allow]`), as inner attributes
|
|
/// (`#![allow]`) are usually used to enable or disable lints on a global scale.
|
|
///
|
|
/// ### Why is this bad?
|
|
///
|
|
/// `#[expect]` attributes suppress the lint emission, but emit a warning, if
|
|
/// the expectation is unfulfilled. This can be useful to be notified when the
|
|
/// lint is no longer triggered.
|
|
///
|
|
/// ### Example
|
|
/// ```rust,ignore
|
|
/// #[allow(unused_mut)]
|
|
/// fn foo() -> usize {
|
|
/// let mut a = Vec::new();
|
|
/// a.len()
|
|
///}
|
|
/// ```
|
|
/// Use instead:
|
|
/// ```rust,ignore
|
|
/// # #![feature(lint_reasons)]
|
|
/// #[expect(unused_mut)]
|
|
/// fn foo() -> usize {
|
|
/// let mut a = Vec::new();
|
|
/// a.len()
|
|
/// }
|
|
/// ```
|
|
#[clippy::version = "1.69.0"]
|
|
pub ALLOW_ATTRIBUTES,
|
|
restriction,
|
|
"`#[allow]` will not trigger if a warning isn't found. `#[expect]` triggers if there are no warnings."
|
|
}
|
|
|
|
declare_lint_pass!(AllowAttribute => [ALLOW_ATTRIBUTES]);
|
|
|
|
impl LateLintPass<'_> for AllowAttribute {
|
|
// Separate each crate's features.
|
|
fn check_attribute(&mut self, cx: &LateContext<'_>, attr: &ast::Attribute) {
|
|
if_chain! {
|
|
if cx.tcx.features().lint_reasons;
|
|
if let AttrStyle::Outer = attr.style;
|
|
if let Some(ident) = attr.ident();
|
|
if ident.name == rustc_span::symbol::sym::allow;
|
|
then {
|
|
span_lint_and_sugg(
|
|
cx,
|
|
ALLOW_ATTRIBUTES,
|
|
ident.span,
|
|
"#[allow] attribute found",
|
|
"replace it with", "expect".into()
|
|
// format!("expect{}", snippet(
|
|
// cx,
|
|
// ident.span
|
|
// .with_lo(
|
|
// ident.span.hi() + BytePos(2) // Cut *(
|
|
// )
|
|
// .with_hi(
|
|
// attr.meta().unwrap().span.hi() - BytePos(1) // Cut )
|
|
// )
|
|
// , "..."))
|
|
, Applicability::MachineApplicable);
|
|
}
|
|
}
|
|
}
|
|
}
|