diff --git a/src/lists.rs b/src/lists.rs
index d7098d3a3974..a5d2334dcdab 100644
--- a/src/lists.rs
+++ b/src/lists.rs
@@ -602,7 +602,11 @@ where
                         // Match arms may not have trailing comma. In any case, for match arms,
                         // we will assume that the post comment belongs to the next arm if they
                         // do not end with trailing comma.
-                        1
+                        if let Some(newline_index) = newline_index {
+                            newline_index + 1
+                        } else {
+                            0
+                        }
                     }
                 }
                 None => post_snippet
diff --git a/tests/source/match.rs b/tests/source/match.rs
index ebae067b1543..23df0d3b6813 100644
--- a/tests/source/match.rs
+++ b/tests/source/match.rs
@@ -435,6 +435,15 @@ impl<'tcx> Const<'tcx> {
     }
 }
 
+// #2151
+fn issue_2151() {
+    match either {
+        x => {
+
+        }y => ()
+    }
+}
+
 // #2152
 fn issue_2152() {
     match m {
diff --git a/tests/target/match.rs b/tests/target/match.rs
index 34d23630df61..3e04f4ca4be2 100644
--- a/tests/target/match.rs
+++ b/tests/target/match.rs
@@ -128,15 +128,13 @@ fn issue339() {
         h => {
             // comment above block
         }
-        i => {}
-        // comment below block
+        i => {} // comment below block
         j => {
             // comment inside block
         }
         j2 => {
             // comments inside...
-        }
-        // ... and after
+        } // ... and after
         // TODO uncomment when vertical whitespace is handled better
         // k => {
         //
@@ -476,6 +474,14 @@ impl<'tcx> Const<'tcx> {
     }
 }
 
+// #2151
+fn issue_2151() {
+    match either {
+        x => {}
+        y => (),
+    }
+}
+
 // #2152
 fn issue_2152() {
     match m {