-use rustc::hir::{Crate, Expr, ExprKind, QPath};
-use rustc::impl_lint_pass;
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc_session::declare_tool_lint;
-use syntax::ast::AttrKind;
-use syntax::symbol::sym;
-
-use crate::utils::{is_entrypoint_fn, snippet, span_help_and_lint};
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::source::snippet;
+use clippy_utils::{is_entrypoint_fn, is_no_std_crate};
use if_chain::if_chain;
+use rustc_hir::{Expr, ExprKind, QPath};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
declare_clippy_lint! {
- /// **What it does:** Checks for recursion using the entrypoint.
+ /// ### What it does
+ /// Checks for recursion using the entrypoint.
///
- /// **Why is this bad?** Apart from special setups (which we could detect following attributes like #![no_std]),
+ /// ### Why is this bad?
+ /// Apart from special setups (which we could detect following attributes like #![no_std]),
/// recursing into main() seems like an unintuitive antipattern we should be able to detect.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```no_run
/// fn main() {
/// main();
/// }
/// ```
+ #[clippy::version = "1.38.0"]
pub MAIN_RECURSION,
style,
"recursion using the entrypoint"
impl_lint_pass!(MainRecursion => [MAIN_RECURSION]);
-impl LateLintPass<'_, '_> for MainRecursion {
- fn check_crate(&mut self, _: &LateContext<'_, '_>, krate: &Crate<'_>) {
- self.has_no_std_attr = krate.attrs.iter().any(|attr| {
- if let AttrKind::Normal(ref attr) = attr.kind {
- attr.path == sym::no_std
- } else {
- false
- }
- });
+impl LateLintPass<'_> for MainRecursion {
+ fn check_crate(&mut self, cx: &LateContext<'_>) {
+ self.has_no_std_attr = is_no_std_crate(cx);
}
- fn check_expr_post(&mut self, cx: &LateContext<'_, '_>, expr: &Expr<'_>) {
+ fn check_expr_post(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
if self.has_no_std_attr {
return;
}
if_chain! {
if let ExprKind::Call(func, _) = &expr.kind;
- if let ExprKind::Path(path) = &func.kind;
- if let QPath::Resolved(_, path) = &path;
+ if let ExprKind::Path(QPath::Resolved(_, path)) = &func.kind;
if let Some(def_id) = path.res.opt_def_id();
if is_entrypoint_fn(cx, def_id);
then {
- span_help_and_lint(
+ span_lint_and_help(
cx,
MAIN_RECURSION,
func.span,
&format!("recursing into entrypoint `{}`", snippet(cx, func.span, "main")),
+ None,
"consider using another function for this recursion"
)
}