Prepare for rustfmt 2.0

Summary:
Generated by formatting with rustfmt 2.0.0-rc.2 and then a second time with fbsource's current rustfmt (1.4.14).

This results in formatting for which rustfmt 1.4 is idempotent but is closer to the style of rustfmt 2.0, reducing the amount of code that will need to change atomically in that upgrade.

 ---

*Why now?* **:** The 1.x branch is no longer being developed and fixes like rust-lang/rustfmt#4159 (which we need in fbcode) only land to the 2.0 branch.

 ---

Reviewed By: shiqicao

Differential Revision: D23568783

fbshipit-source-id: ccac998bb5edb272b16e9b0b1ad2339e60dad21a

Author: David Tolnay

hphp/hack/src/decl/direct_decl_smart_constructors.rs

@@ -84,7 +84,7 @@ impl<'a> DirectDeclSmartConstructors<'a> {
             let mut qualified_name =
                 String::with_capacity_in(namespace.len() + parts.len() * 10, this.state.arena);
             match parts.first() {
-                Some(Node::Backslash(_)) => (), // Already fully-qualified
+                Some(Node::Backslash(_)) => {} // Already fully-qualified
                 _ => qualified_name.push_str(namespace),
             }
             for part in parts {
@@ -279,7 +279,7 @@ fn read_member_modifiers<'a: 'b, 'b>(modifiers: impl Iterator<Item = &'b Node<'a
             Node::Token(TokenKind::Static) => ret.is_static = true,
             Node::Token(TokenKind::Abstract) => ret.is_abstract = true,
             Node::Token(TokenKind::Final) => ret.is_final = true,
-            _ => (),
+            _ => {}
         }
     }
     ret
@@ -427,7 +427,7 @@ impl<'a> ClassishNameBuilder<'a> {
                 class_name.push_str(name);
                 *self = InClassish(arena.alloc((class_name.into_bump_str(), pos, token_kind)))
             }
-            InClassish(_) => (),
+            InClassish(_) => {}
         }
     }
 
@@ -864,7 +864,7 @@ impl<'a> Node<'a> {
                         arena.alloc(Ty_::Tapply(arena.alloc((class_name, &[][..])))),
                     ));
                 }
-                _ => (),
+                _ => {}
             }
         }
 
@@ -936,7 +936,7 @@ impl<'a> Node<'a> {
                     "__ReturnDisposable" => {
                         attributes.returns_disposable = true;
                     }
-                    _ => (),
+                    _ => {}
                 }
             } else {
                 panic!("Expected an attribute, but was {:?}", self);
@@ -1799,7 +1799,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
 
         // We only want to check the mode if <? is the very first token we see.
         match (&self.state.file_mode_builder, &kind) {
-            (FileModeBuilder::None, TokenKind::Markup) => (),
+            (FileModeBuilder::None, TokenKind::Markup) => {}
             (FileModeBuilder::None, TokenKind::LessThanQuestion) => {
                 self.state.file_mode_builder = FileModeBuilder::Pending
             }
@@ -1814,7 +1814,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
                         Mode::Mstrict
                     });
             }
-            (_, _) => (),
+            (_, _) => {}
         }
 
         let result = match kind {
@@ -2289,7 +2289,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
 
         match (&op, rhs) {
             (Bop::Eq(_), Node::Token(TokenKind::Yield)) => return rhs,
-            _ => (),
+            _ => {}
         }
 
         let pos = unwrap_or_return!(Pos::merge(
@@ -2893,7 +2893,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
             match modifier {
                 Node::Token(TokenKind::Abstract) => class_kind = ClassKind::Cabstract,
                 Node::Token(TokenKind::Final) => final_ = true,
-                _ => (),
+                _ => {}
             }
         }
 
@@ -2923,7 +2923,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
         for attribute in attributes.iter() {
             match attribute {
                 &Node::Attribute(..) => user_attributes_len += 1,
-                _ => (),
+                _ => {}
             }
         }
 
@@ -2961,7 +2961,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
                         methods_len += 1
                     }
                 }
-                _ => (),
+                _ => {}
             }
         }
 
@@ -2982,7 +2982,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
         for attribute in attributes.iter() {
             match attribute {
                 Node::Attribute(attr) => user_attributes.push(self.user_attribute_to_decl(&attr)),
-                _ => (),
+                _ => {}
             }
         }
         // Match ordering of attributes produced by the OCaml decl parser (even
@@ -3041,7 +3041,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
                         methods.push(method.clone());
                     }
                 }
-                _ => (), // It's not our job to report errors here.
+                _ => {} // It's not our job to report errors here.
             }
         }
 
@@ -3381,7 +3381,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
         for attribute in attributes.iter() {
             match attribute {
                 Node::Attribute(attr) => user_attributes.push(self.user_attribute_to_decl(attr)),
-                _ => (),
+                _ => {}
             }
         }
         // Match ordering of attributes produced by the OCaml decl parser (even
@@ -3800,7 +3800,7 @@ impl<'a> FlattenSmartConstructors<'a, State<'a>> for DirectDeclSmartConstructors
                         fold_string_concat(&e1, acc);
                         fold_string_concat(&e2, acc);
                     }
-                    _ => (),
+                    _ => {}
                 }
             }
 

hphp/hack/src/facts/facts_parser.rs

@@ -143,7 +143,7 @@ fn typenames_from_list(list: Node, namespace: &str, names: &mut StringSet, names
                 names.insert(name);
             }
         }),
-        _ => (),
+        _ => {}
     };
 }
 
@@ -416,7 +416,7 @@ fn collect(mut acc: CollectAcc, node: Node) -> CollectAcc {
         FileAttributeSpecification(attributes) => {
             acc.1.file_attributes = attributes_into_facts(&acc.0, *attributes);
         }
-        _ => (),
+        _ => {}
     };
     acc
 }

hphp/hack/src/facts/facts_smart_constructors.rs

@@ -337,7 +337,7 @@ impl<'a> FlattenSmartConstructors<'a, HasScriptContent<'a>> for FactsSmartConstr
                     }
                 }
             }
-            _ => (),
+            _ => {}
         };
         Node::Ignored
     }

hphp/hack/src/hhbc/ast_constant_folder.rs

@@ -278,7 +278,7 @@ fn shape_to_typed_value(
                             return Err(Error::unrecoverable(format!(
                                 "{} is not a valid integer index",
                                 s
-                            )))
+                            )));
                         }
                     }
                 }

hphp/hack/src/hhbc/ast_scope.rs

@@ -60,7 +60,7 @@ impl<'a> Scope<'a> {
                 ScopeItem::Method(md) => {
                     return md.get_span().clone();
                 }
-                _ => (),
+                _ => {}
             }
         }
         Pos::make_none()
@@ -84,7 +84,7 @@ impl<'a> Scope<'a> {
                 ScopeItem::Method(md) => {
                     extend_shallowly(md.get_tparams());
                 }
-                _ => (),
+                _ => {}
             }
         }
         tparams
@@ -102,7 +102,7 @@ impl<'a> Scope<'a> {
                 ScopeItem::Method(md) => {
                     return md.get_tparams();
                 }
-                _ => (),
+                _ => {}
             }
         }
         &[]
@@ -130,7 +130,7 @@ impl<'a> Scope<'a> {
                 ScopeItem::Method(_) => {
                     return true;
                 }
-                _ => (),
+                _ => {}
             }
         }
         false
@@ -150,7 +150,7 @@ impl<'a> Scope<'a> {
                     let fun_kind = f.get_fun_kind();
                     return fun_kind == FunKind::FAsync || fun_kind == FunKind::FAsyncGenerator;
                 }
-                _ => (),
+                _ => {}
             }
         }
         false
@@ -171,7 +171,7 @@ impl<'a> Scope<'a> {
                         return false;
                     }
                 }
-                ScopeItem::Lambda(_) => (),
+                ScopeItem::Lambda(_) => {}
                 _ => return false,
             }
         }
@@ -203,7 +203,7 @@ impl<'a> Scope<'a> {
                 }) => {
                     return *rl;
                 }
-                _ => (),
+                _ => {}
             }
         }
         rx::Level::NonRx
@@ -219,7 +219,7 @@ impl<'a> Scope<'a> {
                 ScopeItem::Function(f) => {
                     return has(f.get_user_attributes());
                 }
-                _ => (),
+                _ => {}
             }
         }
         false

hphp/hack/src/hhbc/closure_convert.rs

@@ -441,7 +441,7 @@ fn make_scope_name(ns: &RcOc<namespace_env::Env>, scope: &ast_scope::Scope) -> S
                     parts.push("::".into())
                 };
             }
-            _ => (),
+            _ => {}
         }
     }
     parts.reverse();

hphp/hack/src/hhbc/emit_adata.rs

@@ -72,7 +72,7 @@ fn rewrite_typed_value(e: &mut Emitter, instr: &mut Instruct) -> Result<()> {
                         return Err(Error::Unrecoverable(format!(
                             "Unknown HhasAdata data: {}",
                             d
-                        )))
+                        )));
                     }
                 }
             }

hphp/hack/src/hhbc/emit_body.rs

@@ -350,7 +350,7 @@ fn make_decl_vars(
     } else {
         match &scope.items[..] {
             [] | [.., ScopeItem::Class(_), _] => move_this(&mut decl_vars),
-            _ => (),
+            _ => {}
         };
         decl_vars
     };
@@ -491,7 +491,7 @@ fn emit_defs(env: &mut Env, emitter: &mut Emitter, prog: &[tast::Def]) -> Result
             Def::Namespace(ns) => emit_defs(env, emitter, &ns.1),
             _ => Ok(instr::empty()),
         }
-    };
+    }
     fn aux(env: &mut Env, emitter: &mut Emitter, defs: &[tast::Def]) -> Result {
         match defs {
             [Def::SetNamespaceEnv(ns), ..] => {
@@ -515,7 +515,7 @@ fn emit_defs(env: &mut Env, emitter: &mut Emitter, prog: &[tast::Def]) -> Result
                 aux(env, emitter, &defs[1..])?,
             ])),
         }
-    };
+    }
     match prog {
         [Def::Stmt(s), ..] if s.1.is_markup() => Ok(InstrSeq::gather(vec![
             emit_statement::emit_markup(emitter, env, s.1.as_markup().unwrap(), true)?,

hphp/hack/src/hhbc/emit_class.rs

@@ -308,11 +308,11 @@ fn emit_reified_extends_params<'a>(
                         &l.iter().collect::<Vec<_>>(),
                     )?,
                     instr::record_reified_generic(),
-                ]))
+                ]));
             }
-            _ => (),
+            _ => {}
         },
-        _ => (),
+        _ => {}
     }
     let hack_arr_dv_arr_mark = e
         .options()