Auto merge of #7643 - jdramani:extra_ptr_dref, r=jdm

Check for Extra pointer dereferencing

Solves issue #7640

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components/compositing/compositor.rs

@@ -681,7 +681,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
 
     fn collect_old_layers(&mut self,
                           pipeline_id: PipelineId,
-                          new_layers: &Vec<LayerProperties>) {
+                          new_layers: &[LayerProperties]) {
         let root_layer = match self.scene.root {
             Some(ref root_layer) => root_layer.clone(),
             None => return,

components/compositing/compositor_layer.rs

@@ -102,7 +102,7 @@ pub trait CompositorLayer {
     fn collect_old_layers<Window>(&self,
                                   compositor: &mut IOCompositor<Window>,
                                   pipeline_id: PipelineId,
-                                  new_layers: &Vec<LayerProperties>)
+                                  new_layers: &[LayerProperties])
                                   where Window: WindowMethods;
 
     /// Destroys all tiles of all layers, including children, *without* sending them back to the
@@ -282,7 +282,7 @@ impl CompositorLayer for Layer<CompositorData> {
     fn collect_old_layers<Window>(&self,
                                   compositor: &mut IOCompositor<Window>,
                                   pipeline_id: PipelineId,
-                                  new_layers: &Vec<LayerProperties>)
+                                  new_layers: &[LayerProperties])
                                   where Window: WindowMethods {
         // Traverse children first so that layers are removed
         // bottom up - allowing each layer being removed to properly

components/net/resource_task.rs

@@ -57,14 +57,14 @@ pub fn start_sending(start_chan: LoadConsumer, metadata: Metadata) -> ProgressSe
 
 /// For use by loaders in responding to a Load message that allows content sniffing.
 pub fn start_sending_sniffed(start_chan: LoadConsumer, metadata: Metadata,
-                             classifier: Arc<MIMEClassifier>, partial_body: &Vec<u8>)
+                             classifier: Arc<MIMEClassifier>, partial_body: &[u8])
                              -> ProgressSender {
     start_sending_sniffed_opt(start_chan, metadata, classifier, partial_body).ok().unwrap()
 }
 
 /// For use by loaders in responding to a Load message that allows content sniffing.
 pub fn start_sending_sniffed_opt(start_chan: LoadConsumer, mut metadata: Metadata,
-                                 classifier: Arc<MIMEClassifier>, partial_body: &Vec<u8>)
+                                 classifier: Arc<MIMEClassifier>, partial_body: &[u8])
                                  -> Result<ProgressSender, ()> {
     if opts::get().sniff_mime_types {
         // TODO: should be calculated in the resource loader, from pull requeset #4094

components/style/animation.rs

@@ -736,8 +736,8 @@ impl Interpolate for TextShadowList {
 /// Check if it's possible to do a direct numerical interpolation
 /// between these two transform lists.
 /// http://dev.w3.org/csswg/css-transforms/#transform-transform-animation
-fn can_interpolate_list(from_list: &Vec<TransformOperation>,
-                        to_list: &Vec<TransformOperation>) -> bool {
+fn can_interpolate_list(from_list: &[TransformOperation],
+                        to_list: &[TransformOperation]) -> bool {
     // Lists must be equal length
     if from_list.len() != to_list.len() {
         return false;
@@ -763,8 +763,8 @@ fn can_interpolate_list(from_list: &Vec<TransformOperation>,
 
 /// Interpolate two transform lists.
 /// http://dev.w3.org/csswg/css-transforms/#interpolation-of-transforms
-fn interpolate_transform_list(from_list: &Vec<TransformOperation>,
-                              to_list: &Vec<TransformOperation>,
+fn interpolate_transform_list(from_list: &[TransformOperation],
+                              to_list: &[TransformOperation],
                               time: f64) -> TransformList {
     let mut result = vec!();
 
@@ -823,7 +823,7 @@ fn interpolate_transform_list(from_list: &Vec<TransformOperation>,
 /// Build an equivalent 'identity transform function list' based
 /// on an existing transform list.
 /// http://dev.w3.org/csswg/css-transforms/#none-transform-animation
-fn build_identity_transform_list(list: &Vec<TransformOperation>) -> Vec<TransformOperation> {
+fn build_identity_transform_list(list: &[TransformOperation]) -> Vec<TransformOperation> {
     let mut result = vec!();
 
     for operation in list {

python/tidy.py

@@ -111,6 +111,7 @@ def check_by_line(file_name, contents):
             check_whitespace(idx, line),
             check_whatwg_url(idx, line),
         )
+
         for error in errors:
             yield error
 
@@ -349,6 +350,10 @@ def check_rust(file_name, contents):
                     yield (idx + 1 - len(mods) + i, message + expected + found)
             mods = []
 
+        # There should not be any extra pointer dereferencing
+        if re.search(r": &Vec<", line) is not None:
+            yield (idx + 1, "use &[T] instead of &Vec<T>")
+
 
 # Avoid flagging <Item=Foo> constructs
 def is_associated_type(match, line, index):