Fix explicit_deref_methods triggering from within proc macros

Signed-off-by: Justus Flügel <justusfluegel@gmail.com>

Author: JustusFluegel

clippy_lints/src/dereference.rs

@@ -3,7 +3,8 @@ use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
 use clippy_utils::sugg::has_enclosing_paren;
 use clippy_utils::ty::{adjust_derefs_manually_drop, implements_trait, is_manually_drop, peel_and_count_ty_refs};
 use clippy_utils::{
-    DefinedTy, ExprUseNode, expr_use_ctxt, get_parent_expr, is_block_like, is_lint_allowed, path_to_local,
+    DefinedTy, ExprUseNode, expr_use_ctxt, get_parent_expr, is_block_like, is_from_proc_macro, is_lint_allowed,
+    path_to_local,
 };
 use rustc_ast::util::parser::ExprPrecedence;
 use rustc_data_structures::fx::FxIndexMap;
@@ -260,6 +261,13 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing<'tcx> {
         };
         self.skip_expr = skip_expr;
 
+        if is_from_proc_macro(cx, expr) {
+            if let Some((state, data)) = self.state.take() {
+                report(cx, expr, state, data, cx.typeck_results());
+            }
+            return;
+        }
+
         match (self.state.take(), kind) {
             (None, kind) => {
                 let expr_ty = typeck.expr_ty(expr);