rust/clippy_lints/src/question_mark_used.rs
2023-04-19 14:55:18 +02:00

53 lines
1.5 KiB
Rust

use clippy_utils::diagnostics::span_lint_and_help;
use clippy_utils::macros::span_is_local;
use rustc_hir::{Expr, ExprKind, MatchSource};
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
declare_clippy_lint! {
/// ### What it does
/// Checks for expressions that use the question mark operator and rejects them.
///
/// ### Why is this bad?
/// Sometimes code wants to avoid the question mark operator because for instance a local
/// block requires a macro to re-throw errors to attach additional information to the
/// error.
///
/// ### Example
/// ```ignore
/// let result = expr?;
/// ```
///
/// Could be written:
///
/// ```ignore
/// utility_macro!(expr);
/// ```
#[clippy::version = "1.69.0"]
pub QUESTION_MARK_USED,
restriction,
"complains if the question mark operator is used"
}
declare_lint_pass!(QuestionMarkUsed => [QUESTION_MARK_USED]);
impl<'tcx> LateLintPass<'tcx> for QuestionMarkUsed {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if let ExprKind::Match(_, _, MatchSource::TryDesugar) = expr.kind {
if !span_is_local(expr.span) {
return;
}
span_lint_and_help(
cx,
QUESTION_MARK_USED,
expr.span,
"question mark operator was used",
None,
"consider using a custom macro or match expression",
);
}
}
}