Resolve: improve detection of unused imports and other miscellaneous improvements

src/librustc/middle/region.rs

@@ -20,7 +20,7 @@ use front::map as ast_map;
 use session::Session;
 use util::nodemap::{FnvHashMap, NodeMap, NodeSet};
 use middle::cstore::InlinedItem;
-use middle::ty::{self, Ty};
+use middle::ty;
 
 use std::cell::RefCell;
 use std::collections::hash_map::Entry;

src/librustc_lint/types.rs

@@ -26,7 +26,6 @@ use std::{i8, i16, i32, i64, u8, u16, u32, u64, f32, f64};
 use syntax::{abi, ast};
 use syntax::attr::{self, AttrMetaMethods};
 use syntax::codemap::{self, Span};
-use syntax::ast::{TyIs, TyUs, TyI8, TyU8, TyI16, TyU16, TyI32, TyU32, TyI64, TyU64};
 
 use rustc_front::hir;
 use rustc_front::intravisit::{self, Visitor};

src/librustc_resolve/build_reduced_graph.rs

@@ -142,29 +142,17 @@ impl<'a, 'b:'a, 'tcx:'b> GraphBuilder<'a, 'b, 'tcx> {
  }
 
  fn block_needs_anonymous_module(&mut self, block: &Block) -> bool {
- // Check each statement.
- for statement in &block.stmts {
- match statement.node {
- StmtDecl(ref declaration, _) => {
- match declaration.node {
- DeclItem(_) => {
- return true;
- }
- _ => {
- // Keep searching.
- }
- }
- }
- _ => {
- // Keep searching.
+ fn is_item(statement: &hir::Stmt) -> bool {
+ if let StmtDecl(ref declaration, _) = statement.node {
+ if let DeclItem(_) = declaration.node {
+ return true;
  }
  }
+ false
  }
 
- // If we found no items, we don't need to create
- // an anonymous module.
-
- return false;
+ // If any statements are items, we need to create an anonymous module
+ block.stmts.iter().any(is_item)
  }
 
  /// Constructs the reduced graph for one item.
@@ -309,7 +297,7 @@ impl<'a, 'b:'a, 'tcx:'b> GraphBuilder<'a, 'b, 'tcx> {
  let external_module = self.new_extern_crate_module(parent_link, def);
  self.define(parent, name, TypeNS, (external_module, sp));
 
- self.build_reduced_graph_for_external_crate(&external_module);
+ self.build_reduced_graph_for_external_crate(external_module);
  }
  parent
  }
@@ -365,7 +353,7 @@ impl<'a, 'b:'a, 'tcx:'b> GraphBuilder<'a, 'b, 'tcx> {
  for variant in &(*enum_definition).variants {
  let item_def_id = self.ast_map.local_def_id(item.id);
  self.build_reduced_graph_for_variant(variant, item_def_id,
-&module, variant_modifiers);
+ module, variant_modifiers);
  }
  parent
  }
@@ -421,7 +409,7 @@ impl<'a, 'b:'a, 'tcx:'b> GraphBuilder<'a, 'b, 'tcx> {
  };
 
  let modifiers = DefModifiers::PUBLIC; // NB: not DefModifiers::IMPORTABLE
- self.define(&module_parent, item.name, ns, (def, item.span, modifiers));
+ self.define(module_parent, item.name, ns, (def, item.span, modifiers));
 
  self.trait_item_map.insert((item.name, def_id), item_def_id);
  }