fix Unparsable code when formmating (#3883)

src/items.rs

@@ -2218,10 +2218,16 @@ fn rewrite_fn_base(
             .map_or(false, |last_line| last_line.contains("//"));
 
         if context.config.version() == Version::Two {
-            result.push(')');
-            if closing_paren_overflow_max_width || params_last_line_contains_comment {
+            if closing_paren_overflow_max_width {
+                result.push(')');
                 result.push_str(&indent.to_string_with_newline(context.config));
                 no_params_and_over_max_width = true;
+            } else if params_last_line_contains_comment {
+                result.push_str(&indent.to_string_with_newline(context.config));
+                result.push(')');
+                no_params_and_over_max_width = true;
+            } else {
+                result.push(')');
             }
         } else {
             if closing_paren_overflow_max_width || params_last_line_contains_comment {

tests/target/issue-3882.rs

@@ -0,0 +1,4 @@
+// rustfmt-version: Two
+fn bar(_t: T, // bar
+) {
+}