Auto merge of #8030 - Manishearth:fix-lint-fn, r=frewsxcv

Fix unrooted_must_root lint to handle arguments/return types properly

r? @jdm

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6 files changed, 12 insertions, 5 deletions

diff --git a/components/script/dom/bindings/global.rs b/components/script/dom/bindings/global.rs
index ea170ab2463..bc5987ae7f7 100644
--- a/components/script/dom/bindings/global.rs
+++ b/components/script/dom/bindings/global.rs
@@ -210,6 +210,7 @@ impl GlobalRoot {
 
 impl GlobalField {
     /// Create a new `GlobalField` from a rooted reference.
+    #[allow(unrooted_must_root)]
     pub fn from_rooted(global: &GlobalRef) -> GlobalField {
         match *global {
             GlobalRef::Window(window) => GlobalField::Window(JS::from_ref(window)),
diff --git a/components/script/dom/bindings/js.rs b/components/script/dom/bindings/js.rs
index e39e5c1f412..16fa12e7189 100644
--- a/components/script/dom/bindings/js.rs
+++ b/components/script/dom/bindings/js.rs
@@ -67,12 +67,14 @@ impl<T: Reflectable> JS<T> {
     }
     /// Create a JS<T> from a Root<T>
     /// XXX Not a great API. Should be a call on Root<T> instead
+    #[allow(unrooted_must_root)]
     pub fn from_rooted(root: &Root<T>) -> JS<T> {
         JS {
             ptr: unsafe { NonZero::new(&**root) }
         }
     }
     /// Create a JS<T> from a &T
+    #[allow(unrooted_must_root)]
     pub fn from_ref(obj: &T) -> JS<T> {
         JS {
             ptr: unsafe { NonZero::new(&*obj) }
@@ -125,6 +127,7 @@ impl<T> PartialEq for LayoutJS<T> {
 
 impl <T> Clone for JS<T> {
     #[inline]
+    #[allow(unrooted_must_root)]
     fn clone(&self) -> JS<T> {
         JS {
             ptr: self.ptr.clone()
@@ -288,6 +291,7 @@ impl<T: Reflectable> MutNullableHeap<JS<T>> {
 }
 
 impl<T: HeapGCValue + Copy> Default for MutNullableHeap<T> {
+    #[allow(unrooted_must_root)]
     fn default() -> MutNullableHeap<T> {
         MutNullableHeap {
             ptr: Cell::new(None)
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 2f9762cd4de..d5e7f5c6e83 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -1352,10 +1352,12 @@ impl Node {
         Node::new_(flags, Some(doc))
     }
 
+    #[allow(unrooted_must_root)]
     pub fn new_document_node() -> Node {
         Node::new_(NodeFlags::new() | IS_IN_DOC, None)
     }
 
+    #[allow(unrooted_must_root)]
     fn new_(flags: NodeFlags, doc: Option<&Document>) -> Node {
         Node {
             eventtarget: EventTarget::new_inherited(),
diff --git a/components/script/dom/servohtmlparser.rs b/components/script/dom/servohtmlparser.rs
index fd854768347..acea9113127 100644
--- a/components/script/dom/servohtmlparser.rs
+++ b/components/script/dom/servohtmlparser.rs
@@ -43,6 +43,7 @@ pub struct Sink {
 }
 
 impl Sink {
+    #[allow(unrooted_must_root)] // method is only run at parse time
     pub fn get_or_create(&self, child: NodeOrText<JS<Node>>) -> Root<Node> {
         match child {
             NodeOrText::AppendNode(n) => n.root(),
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 2fd87cfd19d..f5a3569da13 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -147,10 +147,10 @@ impl WebGLRenderingContext {
         }
     }
 
-    pub fn bound_texture_for(&self, target: u32) -> Option<JS<WebGLTexture>> {
+    pub fn bound_texture_for(&self, target: u32) -> Option<Root<WebGLTexture>> {
         match target {
-            constants::TEXTURE_2D => self.bound_texture_2d.get(),
-            constants::TEXTURE_CUBE_MAP => self.bound_texture_cube_map.get(),
+            constants::TEXTURE_2D => self.bound_texture_2d.get().map(|t| t.root()),
+            constants::TEXTURE_CUBE_MAP => self.bound_texture_cube_map.get().map(|t| t.root()),
 
             _ => unreachable!(),
         }
@@ -906,7 +906,6 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             constants::TEXTURE_2D |
             constants::TEXTURE_CUBE_MAP => {
                 if let Some(texture) = self.bound_texture_for(target) {
-                    let texture = texture.root();
                     let result = texture.r().tex_parameter(target, name, TexParameterValue::Float(value));
                     handle_potential_webgl_error!(self, result);
                 } else {
@@ -924,7 +923,6 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             constants::TEXTURE_2D |
             constants::TEXTURE_CUBE_MAP => {
                 if let Some(texture) = self.bound_texture_for(target) {
-                    let texture = texture.root();
                     let result = texture.r().tex_parameter(target, name, TexParameterValue::Int(value));
                     handle_potential_webgl_error!(self, result);
                 } else {
diff --git a/components/script/page.rs b/components/script/page.rs
index ce778d8bca9..b6b35c6119a 100644
--- a/components/script/page.rs
+++ b/components/script/page.rs
@@ -119,6 +119,7 @@ impl Page {
         old
     }
 
+    #[allow(unrooted_must_root)]
     pub fn set_frame(&self, frame: Option<Frame>) {
         *self.frame.borrow_mut() = frame;
     }