--- /dev/null
+#![crate_type = "proc-macro"]
+#![warn(clippy::needless_pass_by_value)]
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro_derive(Foo)]
+pub fn foo(_input: TokenStream) -> TokenStream {
+ unimplemented!()
+}
+
+#[proc_macro]
+pub fn bar(_input: TokenStream) -> TokenStream {
+ unimplemented!()
+}
+
+#[proc_macro_attribute]
+pub fn baz(_args: TokenStream, _input: TokenStream) -> TokenStream {
+ unimplemented!()
+}