init by copying `ty_search_pat`

1 files changed, 42 insertions, 0 deletions

diff --git a/clippy_utils/src/check_proc_macro.rs b/clippy_utils/src/check_proc_macro.rs
index c4a759e919b..d569865553a 100644
--- a/clippy_utils/src/check_proc_macro.rs
+++ b/clippy_utils/src/check_proc_macro.rs
@@ -13,6 +13,7 @@
 //! if the span is not from a `macro_rules` based macro.
 
 use rustc_abi::ExternAbi;
+use rustc_ast as ast;
 use rustc_ast::AttrStyle;
 use rustc_ast::ast::{AttrKind, Attribute, IntTy, LitIntType, LitKind, StrStyle, TraitObjectSyntax, UintTy};
 use rustc_ast::token::CommentKind;
@@ -411,6 +412,47 @@ fn ty_search_pat(ty: &Ty<'_>) -> (Pat, Pat) {
     }
 }
 
+fn ast_ty_search_pat(ty: &ast::Ty) -> (Pat, Pat) {
+    match ty.kind {
+        TyKind::Slice(..) | TyKind::Array(..) => (Pat::Str("["), Pat::Str("]")),
+        TyKind::Ptr(MutTy { ty, .. }) => (Pat::Str("*"), ty_search_pat(ty).1),
+        TyKind::Ref(_, MutTy { ty, .. }) => (Pat::Str("&"), ty_search_pat(ty).1),
+        TyKind::FnPtr(fn_ptr) => (
+            if fn_ptr.safety.is_unsafe() {
+                Pat::Str("unsafe")
+            } else if fn_ptr.abi != ExternAbi::Rust {
+                Pat::Str("extern")
+            } else {
+                Pat::MultiStr(&["fn", "extern"])
+            },
+            match fn_ptr.decl.output {
+                FnRetTy::DefaultReturn(_) => {
+                    if let [.., ty] = fn_ptr.decl.inputs {
+                        ty_search_pat(ty).1
+                    } else {
+                        Pat::Str("(")
+                    }
+                },
+                FnRetTy::Return(ty) => ty_search_pat(ty).1,
+            },
+        ),
+        TyKind::Never => (Pat::Str("!"), Pat::Str("!")),
+        // Parenthesis are trimmed from the text before the search patterns are matched.
+        // See: `span_matches_pat`
+        TyKind::Tup([]) => (Pat::Str(")"), Pat::Str("(")),
+        TyKind::Tup([ty]) => ty_search_pat(ty),
+        TyKind::Tup([head, .., tail]) => (ty_search_pat(head).0, ty_search_pat(tail).1),
+        TyKind::OpaqueDef(..) => (Pat::Str("impl"), Pat::Str("")),
+        TyKind::Path(qpath) => qpath_search_pat(&qpath),
+        TyKind::Infer(()) => (Pat::Str("_"), Pat::Str("_")),
+        TyKind::TraitObject(_, tagged_ptr) if let TraitObjectSyntax::Dyn = tagged_ptr.tag() => {
+            (Pat::Str("dyn"), Pat::Str(""))
+        },
+        // NOTE: `TraitObject` is incomplete. It will always return true then.
+        _ => (Pat::Str(""), Pat::Str("")),
+    }
+}
+
 fn ident_search_pat(ident: Ident) -> (Pat, Pat) {
     (Pat::Sym(ident.name), Pat::Sym(ident.name))
 }