47 lines
1.3 KiB
Rust
47 lines
1.3 KiB
Rust
use clippy_utils::diagnostics::span_lint_and_help;
|
|
use rustc_ast::ast::{BindingMode, Pat, PatKind};
|
|
use rustc_lint::{EarlyContext, EarlyLintPass};
|
|
use rustc_session::declare_lint_pass;
|
|
|
|
declare_clippy_lint! {
|
|
/// ### What it does
|
|
/// Checks for usages of the `ref` keyword.
|
|
///
|
|
/// ### Why restrict this?
|
|
/// The `ref` keyword can be confusing for people unfamiliar with it, and often
|
|
/// it is more concise to use `&` instead.
|
|
///
|
|
/// ### Example
|
|
/// ```no_run
|
|
/// let opt = Some(5);
|
|
/// if let Some(ref foo) = opt {}
|
|
/// ```
|
|
/// Use instead:
|
|
/// ```no_run
|
|
/// let opt = Some(5);
|
|
/// if let Some(foo) = &opt {}
|
|
/// ```
|
|
#[clippy::version = "1.71.0"]
|
|
pub REF_PATTERNS,
|
|
restriction,
|
|
"use of a ref pattern, e.g. Some(ref value)"
|
|
}
|
|
declare_lint_pass!(RefPatterns => [REF_PATTERNS]);
|
|
|
|
impl EarlyLintPass for RefPatterns {
|
|
fn check_pat(&mut self, cx: &EarlyContext<'_>, pat: &Pat) {
|
|
if let PatKind::Ident(BindingMode::REF, _, _) = pat.kind
|
|
&& !pat.span.from_expansion()
|
|
{
|
|
span_lint_and_help(
|
|
cx,
|
|
REF_PATTERNS,
|
|
pat.span,
|
|
"usage of ref pattern",
|
|
None,
|
|
"consider using `&` for clarity instead",
|
|
);
|
|
}
|
|
}
|
|
}
|