change new line point in the case of no args

src/items.rs

@@ -2064,6 +2064,8 @@ fn rewrite_fn_base(
     } && !fd.inputs.is_empty();
 
     let mut args_last_line_contains_comment = false;
+    let mut no_args_and_over_max_width = false;
+
     if put_args_in_block {
         arg_indent = indent.block_indent(context.config);
         result.push_str(&arg_indent.to_string_with_newline(context.config));
@@ -2083,10 +2085,12 @@ fn rewrite_fn_base(
             .lines()
             .last()
             .map_or(false, |last_line| last_line.contains("//"));
+        result.push(')');
+
         if closing_paren_overflow_max_width || args_last_line_contains_comment {
             result.push_str(&indent.to_string_with_newline(context.config));
+            no_args_and_over_max_width = true;
         }
-        result.push(')');
     }
 
     // Return type.
@@ -2126,7 +2130,9 @@ fn rewrite_fn_base(
             result.push_str(&indent.to_string_with_newline(context.config));
             indent
         } else {
-            result.push(' ');
+            if arg_str.len() != 0 || !no_args_and_over_max_width {
+                result.push(' ');
+            }
             Indent::new(indent.block_indent, last_line_width(&result))
         };
 

tests/source/issue-3278.rs

@@ -0,0 +1,3 @@
+pub fn parse_conditional<'a, I: 'a>() -> impl Parser<Input = I, Output = Expr, PartialState = ()> + 'a
+where I: Stream<Item = char>
+{}

tests/target/issue-3278.rs

@@ -0,0 +1,6 @@
+pub fn parse_conditional<'a, I: 'a>()
+-> impl Parser<Input = I, Output = Expr, PartialState = ()> + 'a
+where
+    I: Stream<Item = char>,
+{
+}

tests/target/long-fn-1.rs

@@ -15,14 +15,14 @@ impl Foo {
 
 // #1843
 #[allow(non_snake_case)]
-pub extern "C" fn Java_com_exonum_binding_storage_indices_ValueSetIndexProxy_nativeContainsByHash(
-) -> bool {
+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> {
+    fn my_function_name_is_way_to_long_but_used_as_a_case_study_or_an_example_its_fine()
+    -> Result<(), String> {
     }
 }