2 use syntax::ast::{Crate, Expr, ExprKind};
3 use syntax::symbol::sym;
4 use rustc::lint::{LintArray, LintPass, EarlyLintPass, EarlyContext};
5 use rustc::{declare_tool_lint, impl_lint_pass};
7 use if_chain::if_chain;
8 use crate::utils::span_help_and_lint;
10 declare_clippy_lint! {
13 "function named `foo`, which is not a descriptive name"
16 pub struct MainRecursion {
20 impl_lint_pass!(MainRecursion => [MAIN_RECURSION]);
23 pub fn new() -> MainRecursion {
25 has_no_std_attr: false
30 impl EarlyLintPass for MainRecursion {
31 fn check_crate(&mut self, _: &EarlyContext<'_>, krate: &Crate) {
32 self.has_no_std_attr = krate.attrs.iter().any(|attr| attr.path == sym::no_std);
35 fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
36 if self.has_no_std_attr {
41 if let ExprKind::Call(func, _) = &expr.node;
42 if let ExprKind::Path(_, path) = &func.node;
43 if *path == sym::main;
49 "You are recursing into main()",
50 "Consider using another function for this recursion"