Add check_generic_arg early pass

Author: spastorino

compiler/rustc_ast/src/visit.rs

@@ -200,11 +200,7 @@ pub trait Visitor<'ast>: Sized {
         walk_generic_args(self, path_span, generic_args)
     }
     fn visit_generic_arg(&mut self, generic_arg: &'ast GenericArg) {
-        match generic_arg {
-            GenericArg::Lifetime(lt) => self.visit_lifetime(lt),
-            GenericArg::Type(ty) => self.visit_ty(ty),
-            GenericArg::Const(ct) => self.visit_anon_const(ct),
-        }
+        walk_generic_arg(self, generic_arg)
     }
     fn visit_assoc_ty_constraint(&mut self, constraint: &'ast AssocTyConstraint) {
         walk_assoc_ty_constraint(self, constraint)
@@ -486,6 +482,17 @@ where
     }
 }
 
+pub fn walk_generic_arg<'a, V>(visitor: &mut V, generic_arg: &'a GenericArg)
+where
+    V: Visitor<'a>,
+{
+    match generic_arg {
+        GenericArg::Lifetime(lt) => visitor.visit_lifetime(lt),
+        GenericArg::Type(ty) => visitor.visit_ty(ty),
+        GenericArg::Const(ct) => visitor.visit_anon_const(ct),
+    }
+}
+
 pub fn walk_assoc_ty_constraint<'a, V: Visitor<'a>>(
     visitor: &mut V,
     constraint: &'a AssocTyConstraint,

compiler/rustc_lint/src/early.rs

@@ -195,6 +195,11 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
         run_early_pass!(self, check_expr_post, e);
     }
 
+    fn visit_generic_arg(&mut self, arg: &'a ast::GenericArg) {
+        run_early_pass!(self, check_generic_arg, arg);
+        ast_visit::walk_generic_arg(self, arg);
+    }
+
     fn visit_generic_param(&mut self, param: &'a ast::GenericParam) {
         run_early_pass!(self, check_generic_param, param);
         ast_visit::walk_generic_param(self, param);

compiler/rustc_lint/src/passes.rs

@@ -33,6 +33,7 @@ macro_rules! late_lint_methods {
             fn check_expr(a: &$hir hir::Expr<$hir>);
             fn check_expr_post(a: &$hir hir::Expr<$hir>);
             fn check_ty(a: &$hir hir::Ty<$hir>);
+            fn check_generic_arg(a: &$hir hir::GenericArg<$hir>);
             fn check_generic_param(a: &$hir hir::GenericParam<$hir>);
             fn check_generics(a: &$hir hir::Generics<$hir>);
             fn check_where_predicate(a: &$hir hir::WherePredicate<$hir>);
@@ -176,6 +177,7 @@ macro_rules! early_lint_methods {
             fn check_expr(a: &ast::Expr);
             fn check_expr_post(a: &ast::Expr);
             fn check_ty(a: &ast::Ty);
+            fn check_generic_arg(a: &ast::GenericArg);
             fn check_generic_param(a: &ast::GenericParam);
             fn check_generics(a: &ast::Generics);
             fn check_where_predicate(a: &ast::WherePredicate);