mbe: Add test for macro_rules attributes

Test macros via path and local macros.

Author: joshtriplett

tests/ui/macros/macro-rules-attr.rs

@@ -0,0 +1,90 @@
+//@ run-pass
+//@ check-run-results
+#![feature(macro_attr)]
+#![warn(unused)]
+
+#[macro_export]
+macro_rules! exported_attr {
+    attr($($args:tt)*) { $($body:tt)* } => {
+        println!(
+            "exported_attr: args={:?}, body={:?}",
+            stringify!($($args)*),
+            stringify!($($body)*),
+        );
+    };
+    { $($args:tt)* } => {
+        println!("exported_attr!({:?})", stringify!($($args)*));
+    };
+    attr() {} => {
+        unused_rule();
+    };
+    attr() {} => {
+        compile_error!();
+    };
+    {} => {
+        unused_rule();
+    };
+    {} => {
+        compile_error!();
+    };
+}
+
+macro_rules! local_attr {
+    attr($($args:tt)*) { $($body:tt)* } => {
+        println!(
+            "local_attr: args={:?}, body={:?}",
+            stringify!($($args)*),
+            stringify!($($body)*),
+        );
+    };
+    { $($args:tt)* } => {
+        println!("local_attr!({:?})", stringify!($($args)*));
+    };
+    attr() {} => { //~ WARN: never used
+        unused_rule();
+    };
+    attr() {} => {
+        compile_error!();
+    };
+    {} => { //~ WARN: never used
+        unused_rule();
+    };
+    {} => {
+        compile_error!();
+    };
+}
+
+fn main() {
+    #[crate::exported_attr]
+    struct S;
+    #[::exported_attr(arguments, key = "value")]
+    fn func(_arg: u32) {}
+    #[self::exported_attr(1)]
+    #[self::exported_attr(2)]
+    struct Twice;
+
+    crate::exported_attr!();
+    crate::exported_attr!(invoked, arguments);
+
+    #[exported_attr]
+    struct S;
+    #[exported_attr(arguments, key = "value")]
+    fn func(_arg: u32) {}
+    #[exported_attr(1)]
+    #[exported_attr(2)]
+    struct Twice;
+
+    exported_attr!();
+    exported_attr!(invoked, arguments);
+
+    #[local_attr]
+    struct S;
+    #[local_attr(arguments, key = "value")]
+    fn func(_arg: u32) {}
+    #[local_attr(1)]
+    #[local_attr(2)]
+    struct Twice;
+
+    local_attr!();
+    local_attr!(invoked, arguments);
+}

tests/ui/macros/macro-rules-attr.run.stdout

@@ -0,0 +1,15 @@
+exported_attr: args="", body="struct S;"
+exported_attr: args="arguments, key = \"value\"", body="fn func(_arg: u32) {}"
+exported_attr: args="1", body="#[self::exported_attr(2)] struct Twice;"
+exported_attr!("")
+exported_attr!("invoked, arguments")
+exported_attr: args="", body="struct S;"
+exported_attr: args="arguments, key = \"value\"", body="fn func(_arg: u32) {}"
+exported_attr: args="1", body="#[exported_attr(2)] struct Twice;"
+exported_attr!("")
+exported_attr!("invoked, arguments")
+local_attr: args="", body="struct S;"
+local_attr: args="arguments, key = \"value\"", body="fn func(_arg: u32) {}"
+local_attr: args="1", body="#[local_attr(2)] struct Twice;"
+local_attr!("")
+local_attr!("invoked, arguments")

tests/ui/macros/macro-rules-attr.stderr

@@ -0,0 +1,21 @@
+warning: rule #3 of macro `local_attr` is never used
+  --> $DIR/macro-rules-attr.rs:43:9
+   |
+LL |     attr() {} => {
+   |         ^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/macro-rules-attr.rs:4:9
+   |
+LL | #![warn(unused)]
+   |         ^^^^^^
+   = note: `#[warn(unused_macro_rules)]` implied by `#[warn(unused)]`
+
+warning: rule #5 of macro `local_attr` is never used
+  --> $DIR/macro-rules-attr.rs:49:5
+   |
+LL |     {} => {
+   |     ^^
+
+warning: 2 warnings emitted
+