Make Visitor::FnKind and MutVisitor::FnKind compatible

Author: maxcabrajac

src/items.rs

@@ -3449,21 +3449,14 @@ impl Rewrite for ast::ForeignItem {
                     ref generics,
                     ref body,
                 } = **fn_kind;
-                if let Some(ref body) = body {
+                if body.is_some() {
                     let mut visitor = FmtVisitor::from_context(context);
                     visitor.block_indent = shape.indent;
                     visitor.last_pos = self.span.lo();
                     let inner_attrs = inner_attributes(&self.attrs);
                     let fn_ctxt = visit::FnCtxt::Foreign;
                     visitor.visit_fn(
-                        visit::FnKind::Fn(
-                            fn_ctxt,
-                            self.ident,
-                            sig,
-                            &self.vis,
-                            generics,
-                            Some(body),
-                        ),
+                        visit::FnKind::Fn(fn_ctxt, &self.ident, sig, &self.vis, generics, body),
                         &sig.decl,
                         self.span,
                         defaultness,

src/visitor.rs

@@ -390,7 +390,7 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                 block = b;
                 self.rewrite_fn_before_block(
                     indent,
-                    ident,
+                    *ident,
                     &FnSig::from_fn_kind(&fk, fd, defaultness),
                     mk_sp(s.lo(), b.span.lo()),
                 )
@@ -540,21 +540,14 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                         ref generics,
                         ref body,
                     } = **fn_kind;
-                    if let Some(ref body) = body {
+                    if body.is_some() {
                         let inner_attrs = inner_attributes(&item.attrs);
                         let fn_ctxt = match sig.header.ext {
                             ast::Extern::None => visit::FnCtxt::Free,
                             _ => visit::FnCtxt::Foreign,
                         };
                         self.visit_fn(
-                            visit::FnKind::Fn(
-                                fn_ctxt,
-                                item.ident,
-                                sig,
-                                &item.vis,
-                                generics,
-                                Some(body),
-                            ),
+                            visit::FnKind::Fn(fn_ctxt, &item.ident, sig, &item.vis, generics, body),
                             &sig.decl,
                             item.span,
                             defaultness,
@@ -648,11 +641,11 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                     ref generics,
                     ref body,
                 } = **fn_kind;
-                if let Some(ref body) = body {
+                if body.is_some() {
                     let inner_attrs = inner_attributes(&ai.attrs);
                     let fn_ctxt = visit::FnCtxt::Assoc(assoc_ctxt);
                     self.visit_fn(
-                        visit::FnKind::Fn(fn_ctxt, ai.ident, sig, &ai.vis, generics, Some(body)),
+                        visit::FnKind::Fn(fn_ctxt, &ai.ident, sig, &ai.vis, generics, body),
                         &sig.decl,
                         ai.span,
                         defaultness,