factor out is_automatically_derived util fn

clippy_lints/src/derive.rs

@@ -3,10 +3,9 @@ use rustc::ty::subst::Subst;
 use rustc::ty::TypeVariants;
 use rustc::ty;
 use rustc::hir::*;
-use syntax::ast::{Attribute, MetaItemKind};
 use syntax::codemap::Span;
 use utils::paths;
-use utils::{match_path, span_lint_and_then};
+use utils::{is_automatically_derived, match_path, span_lint_and_then};
 
 /// **What it does:** Checks for deriving `Hash` but implementing `PartialEq`
 /// explicitly.
@@ -75,7 +74,7 @@ impl LateLintPass for Derive {
     fn check_item(&mut self, cx: &LateContext, item: &Item) {
         if let ItemImpl(_, _, _, Some(ref trait_ref), _, _) = item.node {
             let ty = cx.tcx.lookup_item_type(cx.tcx.map.local_def_id(item.id)).ty;
-            let is_automatically_derived = item.attrs.iter().any(is_automatically_derived);
+            let is_automatically_derived = is_automatically_derived(&*item.attrs);
 
             check_hash_peq(cx, item.span, trait_ref, ty, is_automatically_derived);
 
@@ -97,7 +96,7 @@ fn check_hash_peq<'a, 'tcx: 'a>(cx: &LateContext<'a, 'tcx>, span: Span, trait_re
 
         // Look for the PartialEq implementations for `ty`
         peq_trait_def.for_each_relevant_impl(cx.tcx, ty, |impl_id| {
-            let peq_is_automatically_derived = cx.tcx.get_attrs(impl_id).iter().any(is_automatically_derived);
+            let peq_is_automatically_derived = is_automatically_derived(&cx.tcx.get_attrs(impl_id));
 
             if peq_is_automatically_derived == hash_is_automatically_derived {
                 return;
@@ -174,12 +173,3 @@ fn check_copy_clone<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, item: &Item, trait_ref
                            });
     }
 }
-
-/// Checks for the `#[automatically_derived]` attribute all `#[derive]`d implementations have.
-fn is_automatically_derived(attr: &Attribute) -> bool {
-    if let MetaItemKind::Word(ref word) = attr.node.value.node {
-        word == &"automatically_derived"
-    } else {
-        false
-    }
-}

clippy_lints/src/utils/inspector.rs

@@ -4,7 +4,8 @@
 
 use rustc::lint::*;
 use rustc::hir;
-use syntax::ast::{Attribute, MetaItemKind};
+use syntax::ast::Attribute;
+use syntax::attr;
 
 /// **What it does:** Dumps every ast/hir node which has the `#[clippy_dump]` attribute
 ///
@@ -128,10 +129,7 @@ impl LateLintPass for Pass {
 }
 
 fn has_attr(attrs: &[Attribute]) -> bool {
-    attrs.iter().any(|attr| match attr.node.value.node {
-        MetaItemKind::Word(ref word) => word == "clippy_dump",
-        _ => false,
-    })
+    attr::contains_name(attrs, "clippy_dump")
 }
 
 fn print_decl(cx: &LateContext, decl: &hir::Decl) {

clippy_lints/src/utils/mod.rs

@@ -14,6 +14,7 @@ use std::env;
 use std::mem;
 use std::str::FromStr;
 use syntax::ast::{self, LitKind};
+use syntax::attr;
 use syntax::codemap::{ExpnFormat, ExpnInfo, MultiSpan, Span, DUMMY_SP};
 use syntax::errors::DiagnosticBuilder;
 use syntax::ptr::P;
@@ -761,3 +762,8 @@ pub fn is_refutable(cx: &LateContext, pat: &Pat) -> bool {
         }
     }
 }
+
+/// Checks for the `#[automatically_derived]` attribute all `#[derive]`d implementations have.
+pub fn is_automatically_derived(attrs: &[ast::Attribute]) -> bool {
+    attr::contains_name(attrs, "automatically_derived")
+}