Merge pull request rust-lang#3010 from topecongiro/issue-3009

Refactor the corner case of handling long function

Author: nrc

src/items.rs

@@ -2040,18 +2040,16 @@ fn rewrite_fn_base(
         let used_width = last_line_used_width(&result, indent.width()) + first_line_width(&ret_str);
         // Put the closing brace on the next line if it overflows the max width.
         // 1 = `)`
-        if fd.inputs.is_empty() && used_width + 1 > context.config.max_width() {
-            result.push('\n');
-        }
+        let closing_paren_overflow_max_width =
+            fd.inputs.is_empty() && used_width + 1 > context.config.max_width();
         // If the last line of args contains comment, we cannot put the closing paren
         // on the same line.
-        if arg_str
+        args_last_line_contains_comment = arg_str
             .lines()
             .last()
-            .map_or(false, |last_line| last_line.contains("//"))
-        {
-            args_last_line_contains_comment = true;
-            result.push_str(&arg_indent.to_string_with_newline(context.config));
+            .map_or(false, |last_line| last_line.contains("//"));
+        if closing_paren_overflow_max_width || args_last_line_contains_comment {
+            result.push_str(&indent.to_string_with_newline(context.config));
         }
         result.push(')');
     }

tests/source/long-fn-1.rs

@@ -0,0 +1,20 @@
+// Tests that a function which is almost short enough, but not quite, gets
+// formatted correctly.
+
+impl Foo {
+    fn some_input(&mut self, input: Input, input_path: Option<PathBuf>, ) -> (Input, Option<PathBuf>) {}
+
+    fn some_inpu(&mut self, input: Input, input_path: Option<PathBuf>) -> (Input, Option<PathBuf>) {}
+}
+
+// #1843
+#[allow(non_snake_case)]
+pub extern "C" fn Java_com_exonum_binding_storage_indices_ValueSetIndexProxy_nativeContainsByHash() -> bool {
+    false
+}
+
+// #3009
+impl Something {
+    fn my_function_name_is_way_to_long_but_used_as_a_case_study_or_an_example_its_fine(
+) -> Result<  (), String  > {}
+}

tests/target/long-fn-1.rs

@@ -19,3 +19,10 @@ pub extern "C" fn Java_com_exonum_binding_storage_indices_ValueSetIndexProxy_nat
 ) -> bool {
     false
 }
+
+// #3009
+impl Something {
+    fn my_function_name_is_way_to_long_but_used_as_a_case_study_or_an_example_its_fine(
+    ) -> Result<(), String> {
+    }
+}