Fix some Clippy lints.

components/bluetooth_traits/blocklist.rs

@@ -8,10 +8,9 @@ use std::cell::RefCell;
 use std::collections::HashMap;
 use std::string::String;
 
-const EXCLUDE_READS: &'static str = "exclude-reads";
-const EXCLUDE_WRITES: &'static str = "exclude-writes";
-const VALID_UUID_REGEX: &'static str =
-    "^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}";
+const EXCLUDE_READS: &str = "exclude-reads";
+const EXCLUDE_WRITES: &str = "exclude-writes";
+const VALID_UUID_REGEX: &str = "^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}";
 
 thread_local!(pub static BLUETOOTH_BLOCKLIST: RefCell<BluetoothBlocklist> =
               RefCell::new(BluetoothBlocklist(parse_blocklist())));
@@ -108,5 +107,5 @@ fn parse_blocklist() -> Option<HashMap<String, Blocklist>> {
         result.insert(uuid.to_string(), exclude_type);
     }
     // Step 5
-    return Some(result);
+    Some(result)
 }

components/bluetooth_traits/scanfilter.rs

@@ -44,16 +44,16 @@ impl BluetoothScanfilter {
         service_data: Option<ServiceData>,
     ) -> BluetoothScanfilter {
         BluetoothScanfilter {
-            name: name,
-            name_prefix: name_prefix,
+            name,
+            name_prefix,
             services: ServiceUUIDSequence::new(services),
             manufacturer_data: manufacturer_data,
-            service_data: service_data,
+            service_data,
         }
     }
 
     pub fn get_name(&self) -> Option<&str> {
-        self.name.as_ref().map(|s| s.as_str())
+        self.name.as_deref()
     }
 
     pub fn get_name_prefix(&self) -> &str {

components/config/opts.rs

@@ -432,7 +432,7 @@ fn print_debug_usage(app: &str) -> ! {
         "Emit native OS signposts for profile events (currently macOS only)",
     );
 
-    println!("");
+    println!();
 
     process::exit(0)
 }

components/config_plugins/lib.rs

@@ -68,7 +68,7 @@ impl Build {
             self.path_stack.push(field.name.clone());
 
             if let FieldType::NewTypeDef(new_def) = &field.field_type {
-                self.walk(&new_def)?;
+                self.walk(new_def)?;
             } else {
                 let pref_name =
                     self.pref_name(field, &self.path_stack[..self.path_stack.len() - 1]);
@@ -154,7 +154,7 @@ impl Build {
                 }
             },
             FieldType::Existing(type_name) => {
-                let pref_name = self.pref_name(field, &path_stack);
+                let pref_name = self.pref_name(field, path_stack);
                 let attributes = field.get_attributes(&pref_name);
                 quote! {
                     #attributes

components/devtools_traits/lib.rs

@@ -334,7 +334,7 @@ pub enum NetworkEvent {
 impl TimelineMarker {
     pub fn start(name: String) -> StartedTimelineMarker {
         StartedTimelineMarker {
-            name: name,
+            name,
             start_time: PreciseTime::now(),
             start_stack: None,
         }

components/hashglobe/src/alloc.rs

@@ -36,12 +36,11 @@ mod platform {
 
     #[inline]
     pub unsafe fn alloc(size: usize, align: usize) -> *mut u8 {
-        let ptr = if align <= MIN_ALIGN {
+        if align <= MIN_ALIGN {
             libc::malloc(size) as *mut u8
         } else {
             aligned_malloc(size, align)
-        };
-        ptr
+        }
     }
 
     #[inline]

components/hashglobe/src/shim.rs

@@ -49,6 +49,7 @@ impl<T: 'static> Shared<T> {
         }
     }
 
+    #[allow(clippy::mut_from_ref)]
     pub unsafe fn as_mut(&self) -> &mut T {
         &mut *self.ptr.as_ptr()
     }

components/hashglobe/src/table.rs

@@ -202,7 +202,7 @@ impl SafeHash {
         // effectively reducing the hashes by one bit.
         //
         // Truncate hash to fit in `HashUint`.
-        let hash_bits = size_of::<HashUint>() * 8;
+        let hash_bits = HashUint::BITS;
         SafeHash {
             hash: (1 << (hash_bits - 1)) | (hash as HashUint),
         }
@@ -243,7 +243,7 @@ impl<K, V> RawBucket<K, V> {
         self.hash_start.offset(self.idx as isize)
     }
     unsafe fn pair(&self) -> *mut (K, V) {
-        self.pair_start.offset(self.idx as isize) as *mut (K, V)
+        self.pair_start.add(self.idx) as *mut (K, V)
     }
     unsafe fn hash_pair(&self) -> (*mut HashUint, *mut (K, V)) {
         (self.hash(), self.pair())
@@ -824,7 +824,7 @@ impl<K, V> RawTable<K, V> {
         unsafe {
             RawBucket {
                 hash_start: buffer as *mut HashUint,
-                pair_start: buffer.offset(pairs_offset as isize) as *const (K, V),
+                pair_start: buffer.add(pairs_offset) as *const (K, V),
                 idx: index,
                 _marker: marker::PhantomData,
             }

components/msg/constellation_msg.rs

@@ -637,7 +637,7 @@ impl fmt::Debug for HangProfile {
 
         write!(fmt, "HangProfile backtrace:")?;
 
-        if self.backtrace.len() == 0 {
+        if self.backtrace.is_empty() {
             write!(fmt, "backtrace failed to resolve")?;
             return Ok(());
         }

components/net_traits/filemanager_thread.rs

@@ -57,7 +57,7 @@ impl RelativePos {
     pub fn from_opts(start: Option<i64>, end: Option<i64>) -> RelativePos {
         RelativePos {
             start: start.unwrap_or(0),
-            end: end,
+            end,
         }
     }
 

components/net_traits/response.rs

@@ -226,7 +226,7 @@ impl Response {
 
     /// Convert to a filtered response, of type `filter_type`.
     /// Do not use with type Error or Default
-    #[cfg_attr(rustfmt, rustfmt_skip)]
+    #[rustfmt::skip]
     pub fn to_filtered(self, filter_type: ResponseType) -> Response {
         match filter_type {
             ResponseType::Default |

components/script_plugins/lib.rs

@@ -286,21 +286,21 @@ impl<'tcx> LateLintPass<'tcx> for UnrootedPass {
                 }
             }
 
-            if !in_new_function {
-                if is_unrooted_ty(&self.symbols, cx, sig.output().skip_binder(), false) {
-                    cx.lint(UNROOTED_MUST_ROOT, |lint| {
-                        lint.build("Type must be rooted")
-                            .set_span(decl.output.span())
-                            .emit()
-                    })
-                }
+            if !in_new_function &&
+                is_unrooted_ty(&self.symbols, cx, sig.output().skip_binder(), false)
+            {
+                cx.lint(UNROOTED_MUST_ROOT, |lint| {
+                    lint.build("Type must be rooted")
+                        .set_span(decl.output.span())
+                        .emit()
+                })
             }
         }
 
         let mut visitor = FnDefVisitor {
             symbols: &self.symbols,
-            cx: cx,
-            in_new_function: in_new_function,
+            cx,
+            in_new_function,
         };
         visit::walk_expr(&mut visitor, &body.value);
     }
@@ -331,7 +331,7 @@ impl<'a, 'tcx> visit::Visitor<'tcx> for FnDefVisitor<'a, 'tcx> {
 
         match expr.kind {
             // Trait casts from #[unrooted_must_root_lint::must_root] types are not allowed
-            ExprKind::Cast(ref subexpr, _) => require_rooted(cx, self.in_new_function, &*subexpr),
+            ExprKind::Cast(subexpr, _) => require_rooted(cx, self.in_new_function, &subexpr),
             // This catches assignments... the main point of this would be to catch mutable
             // references to `JS<T>`.
             // FIXME: Enable this? Triggers on certain kinds of uses of DomRefCell.
@@ -362,7 +362,7 @@ impl<'a, 'tcx> visit::Visitor<'tcx> for FnDefVisitor<'a, 'tcx> {
             hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, ..) |
             hir::PatKind::Binding(hir::BindingAnnotation::Mutable, ..) => {
                 let ty = cx.typeck_results().pat_ty(pat);
-                if is_unrooted_ty(&self.symbols, cx, ty, self.in_new_function) {
+                if is_unrooted_ty(self.symbols, cx, ty, self.in_new_function) {
                     cx.lint(UNROOTED_MUST_ROOT, |lint| {
                         lint.build(&format!("Expression of type {:?} must be rooted", ty))
                             .set_span(pat.span)

components/servo_arc/lib.rs

@@ -831,6 +831,7 @@ impl<H, T> Arc<HeaderSlice<H, [T]>> {
     }
 
     #[inline]
+    #[allow(clippy::uninit_vec)]
     unsafe fn allocate_buffer<W>(size: usize) -> *mut u8 {
         // We use Vec because the underlying allocation machinery isn't
         // available in stable Rust. To avoid alignment issues, we allocate
@@ -1101,9 +1102,7 @@ impl<T> Clone for RawOffsetArc<T> {
 
 impl<T> Drop for RawOffsetArc<T> {
     fn drop(&mut self) {
-        let _ = Arc::from_raw_offset(RawOffsetArc {
-            ptr: self.ptr.clone(),
-        });
+        let _ = Arc::from_raw_offset(RawOffsetArc { ptr: self.ptr });
     }
 }
 
@@ -1117,10 +1116,6 @@ impl<T: PartialEq> PartialEq for RawOffsetArc<T> {
     fn eq(&self, other: &RawOffsetArc<T>) -> bool {
         *(*self) == *(*other)
     }
-
-    fn ne(&self, other: &RawOffsetArc<T>) -> bool {
-        *(*self) != *(*other)
-    }
 }
 
 impl<T> RawOffsetArc<T> {
@@ -1252,7 +1247,7 @@ impl<'a, T> ArcBorrow<'a, T> {
     /// Compare two `ArcBorrow`s via pointer equality. Will only return
     /// true if they come from the same allocation
     pub fn ptr_eq(this: &Self, other: &Self) -> bool {
-        this.0 as *const T == other.0 as *const T
+        std::ptr::eq(this.0, other.0)
     }
 
     /// Temporarily converts |self| into a bonafide Arc and exposes it to the

components/style_derive/to_css.rs

@@ -123,7 +123,7 @@ fn derive_variant_fields_expr(
     let mut iter = bindings
         .iter()
         .filter_map(|binding| {
-            let attrs = cg::parse_field_attrs::<CssFieldAttrs>(&binding.ast());
+            let attrs = cg::parse_field_attrs::<CssFieldAttrs>(binding.ast());
             if attrs.skip {
                 return None;
             }