Extract fn rewrite methods from RewriteVisitor

src/types.rs

@@ -492,13 +492,14 @@ impl Rewrite for ast::Ty {
                     None
                 }
             }
-            ast::TyBareFn(..) => {
+            ast::TyBareFn(ref bare_fn) => bare_fn.rewrite(context, width, offset),
-                wrap_str(pprust::ty_to_string(self),
-                         context.config.max_width,
-                         width,
-                         offset)
-            }
             ast::TyMac(..) | ast::TyTypeof(..) => unreachable!(),
         }
     }
 }
+
+impl Rewrite for ast::BareFnTy {
+    fn rewrite(&self, context: &RewriteContext, width: usize, offset: Indent) -> Option<String> {
+        None
+    }
+}

src/visitor.rs

@@ -220,8 +220,11 @@ impl<'a> FmtVisitor<'a> {
                 self.last_pos = item.span.hi;
             }
             ast::Item_::ItemStruct(ref def, ref generics) => {
+                let rewrite = {
                     let indent = self.block_indent;
-                let rewrite = self.format_struct("struct ",
+                    let context = self.get_context();
+                    ::items::format_struct(&context,
+                                           "struct ",
                                            item.ident,
                                            item.vis,
                                            def,
@@ -233,7 +236,8 @@ impl<'a> FmtVisitor<'a> {
                                 ast::VariantData::Tuple(..) => s + ";",
                                 _ => s,
                             }
-                                  });
+                        })
+                };
                 self.push_rewrite(item.span, rewrite);
             }
             ast::Item_::ItemEnum(ref def, ref generics) => {