53 lines
1.5 KiB
Rust
53 lines
1.5 KiB
Rust
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use clippy_utils::diagnostics::span_lint_and_help;
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use clippy_utils::macros::span_is_local;
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use rustc_hir::{Expr, ExprKind, MatchSource};
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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 expressions that use the question mark operator and rejects them.
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///
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/// ### Why is this bad?
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/// Sometimes code wants to avoid the question mark operator because for instance a local
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/// block requires a macro to re-throw errors to attach additional information to the
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/// error.
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///
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/// ### Example
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/// ```ignore
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/// let result = expr?;
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/// ```
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///
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/// Could be written:
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///
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/// ```ignore
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/// utility_macro!(expr);
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/// ```
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#[clippy::version = "pre 1.29.0"]
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pub QUESTION_MARK_USED,
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restriction,
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"complains if the question mark operator is used"
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}
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declare_lint_pass!(QuestionMarkUsed => [QUESTION_MARK_USED]);
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impl<'tcx> LateLintPass<'tcx> for QuestionMarkUsed {
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fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
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if let ExprKind::Match(_, _, MatchSource::TryDesugar) = expr.kind {
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if !span_is_local(expr.span) {
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return;
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}
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span_lint_and_help(
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cx,
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QUESTION_MARK_USED,
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expr.span,
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"question mark operator was used",
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None,
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"consider using a custom macro or match expression",
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);
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}
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}
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}
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