Merge pull request #3510 from topecongiro/issue3509

Fix duplication of attributes on a match arm's body

Author: topecongiro

src/matches.rs

@@ -263,7 +263,7 @@ fn rewrite_match_arm(
         false,
     )?;
 
-    let arrow_span = mk_sp(arm.pats.last().unwrap().span.hi(), arm.body.span.lo());
+    let arrow_span = mk_sp(arm.pats.last().unwrap().span.hi(), arm.body.span().lo());
     rewrite_match_body(
         context,
         &arm.body,
@@ -364,7 +364,8 @@ fn rewrite_match_body(
         shape.indent
     };
 
-    let forbid_same_line = has_guard && pats_str.contains('\n') && !is_empty_block;
+    let forbid_same_line =
+        (has_guard && pats_str.contains('\n') && !is_empty_block) || !body.attrs.is_empty();
 
     // Look for comments between `=>` and the start of the body.
     let arrow_comment = {

tests/source/attrib.rs

@@ -217,3 +217,18 @@ fn stmt_expr_attributes() {
     #[must_use]
    foo = false ;
 }
+
+// #3509
+fn issue3509() {
+    match MyEnum {
+        MyEnum::Option1 if cfg!(target_os = "windows") =>
+            #[cfg(target_os = "windows")]{
+                1
+            }
+    }
+    match MyEnum {
+        MyEnum::Option1 if cfg!(target_os = "windows") =>
+            #[cfg(target_os = "windows")]
+                1,
+    }
+}

tests/target/attrib.rs

@@ -252,3 +252,21 @@ fn stmt_expr_attributes() {
     #[must_use]
     foo = false;
 }
+
+// #3509
+fn issue3509() {
+    match MyEnum {
+        MyEnum::Option1 if cfg!(target_os = "windows") =>
+        #[cfg(target_os = "windows")]
+        {
+            1
+        }
+    }
+    match MyEnum {
+        MyEnum::Option1 if cfg!(target_os = "windows") =>
+        {
+            #[cfg(target_os = "windows")]
+            1
+        }
+    }
+}