Auto merge of #4355 - lzutao:macro_expn_try_err, r=flip1995

Fix macro expansion in try_err lint

Fixes #4309

changelog: none

tests/ui/try_err.fixed

@@ -78,3 +78,22 @@ fn main() {
     closure_matches_test().unwrap();
     closure_into_test().unwrap();
 }
+
+macro_rules! bar {
+    () => {
+        String::from("aasdfasdfasdfa")
+    };
+}
+
+macro_rules! foo {
+    () => {
+        bar!()
+    };
+}
+
+pub fn macro_inside(fail: bool) -> Result<i32, String> {
+    if fail {
+        return Err(foo!());
+    }
+    Ok(0)
+}

tests/ui/try_err.rs

@@ -78,3 +78,22 @@ fn main() {
     closure_matches_test().unwrap();
     closure_into_test().unwrap();
 }
+
+macro_rules! bar {
+    () => {
+        String::from("aasdfasdfasdfa")
+    };
+}
+
+macro_rules! foo {
+    () => {
+        bar!()
+    };
+}
+
+pub fn macro_inside(fail: bool) -> Result<i32, String> {
+    if fail {
+        Err(foo!())?;
+    }
+    Ok(0)
+}

tests/ui/try_err.stderr

@@ -28,5 +28,11 @@ error: returning an `Err(_)` with the `?` operator
 LL |                 Err(err)?;
    |                 ^^^^^^^^^ help: try this: `return Err(err.into())`
 
-error: aborting due to 4 previous errors
+error: returning an `Err(_)` with the `?` operator
+  --> $DIR/try_err.rs:96:9
+   |
+LL |         Err(foo!())?;
+   |         ^^^^^^^^^^^^ help: try this: `return Err(foo!())`
+
+error: aborting due to 5 previous errors