61 lines
1.9 KiB
Rust
61 lines
1.9 KiB
Rust
use rustc_hir::{Crate, Expr, ExprKind, QPath};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_session::{declare_tool_lint, impl_lint_pass};
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use crate::utils::{is_entrypoint_fn, is_no_std_crate, snippet, span_lint_and_help};
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use if_chain::if_chain;
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declare_clippy_lint! {
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/// **What it does:** Checks for recursion using the entrypoint.
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///
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/// **Why is this bad?** Apart from special setups (which we could detect following attributes like #![no_std]),
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/// recursing into main() seems like an unintuitive antipattern we should be able to detect.
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///
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/// **Known problems:** None.
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///
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/// **Example:**
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/// ```no_run
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/// fn main() {
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/// main();
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/// }
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/// ```
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pub MAIN_RECURSION,
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style,
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"recursion using the entrypoint"
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}
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#[derive(Default)]
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pub struct MainRecursion {
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has_no_std_attr: bool,
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}
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impl_lint_pass!(MainRecursion => [MAIN_RECURSION]);
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impl LateLintPass<'_, '_> for MainRecursion {
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fn check_crate(&mut self, _: &LateContext<'_, '_>, krate: &Crate<'_>) {
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self.has_no_std_attr = is_no_std_crate(krate);
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}
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fn check_expr_post(&mut self, cx: &LateContext<'_, '_>, expr: &Expr<'_>) {
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if self.has_no_std_attr {
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return;
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}
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if_chain! {
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if let ExprKind::Call(func, _) = &expr.kind;
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if let ExprKind::Path(path) = &func.kind;
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if let QPath::Resolved(_, path) = &path;
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if let Some(def_id) = path.res.opt_def_id();
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if is_entrypoint_fn(cx, def_id);
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then {
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span_lint_and_help(
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cx,
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MAIN_RECURSION,
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func.span,
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&format!("recursing into entrypoint `{}`", snippet(cx, func.span, "main")),
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"consider using another function for this recursion"
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)
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}
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}
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}
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}
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