Add ui test macro-shorthand-issue-140659

Signed-off-by: xizheyin <[email protected]>

Author: xizheyin

tests/ui/typeck/macro-shorthand-issue-140659.rs

@@ -0,0 +1,57 @@
+trait Reencode {
+    type Error;
+    fn tag_index(&mut self, tag: u32) -> Result<u32, Self::Error>;
+}
+
+struct Reencoder;
+impl Reencode for Reencoder {
+    type Error = &'static str;
+    fn tag_index(&mut self, tag: u32) -> Result<u32, Self::Error> {
+        Ok(tag)
+    }
+}
+
+
+enum Operator {
+    Suspend { tag_index: u32 },
+}
+
+enum Instruction {
+    Suspend { tag_index: u32 },
+}
+
+
+macro_rules! for_each_operator {
+    ($m:ident) => {
+        $m! {
+            Suspend { tag_index: u32 } => visit_suspend
+        }
+    };
+}
+
+
+fn process<T: Reencode>(op: &Operator, reencoder: &mut T) -> Instruction {
+    macro_rules! translate {
+        (Suspend { tag_index: $ty:ty } => $visit:ident) => {
+            match op {
+                Operator::Suspend { tag_index } => {
+                    let tag_index = reencoder.tag_index(*tag_index);
+
+                    // KEY POINT: Using field shorthand syntax where the compiler gets confused
+                    // Here tag_index is a Result<u32, E> but we're using it where u32 is expected
+                    Instruction::Suspend { tag_index } //~ ERROR mismatched types [E0308]
+                }
+            }
+        };
+    }
+
+    // This should give the specific error message with the wrong help suggestion
+    for_each_operator!(translate)
+}
+
+fn main() {
+    let mut reencoder = Reencoder;
+    let op = Operator::Suspend { tag_index: 1 };
+
+    let _ = process(&op, &mut reencoder);
+}

tests/ui/typeck/macro-shorthand-issue-140659.stderr

@@ -0,0 +1,20 @@
+error[E0308]: mismatched types
+  --> $DIR/macro-shorthand-issue-140659.rs:42:44
+   |
+LL |                     Instruction::Suspend { tag_index }
+   |                                            ^^^^^^^^^ expected `u32`, found `Result<u32, <T as Reencode>::Error>`
+...
+LL |     for_each_operator!(translate)
+   |     ----------------------------- in this macro invocation
+   |
+   = note: expected type `u32`
+              found enum `Result<u32, <T as Reencode>::Error>`
+   = note: this error originates in the macro `translate` which comes from the expansion of the macro `for_each_operator` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: consider using `Result::expect` to unwrap the `Result<u32, <T as Reencode>::Error>` value, panicking if the value is a `Result::Err`
+   |
+LL |         }: tag_index.expect("REASON")
+   |          ++++++++++++++++++++++++++++
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.