Add guards to almost CanvasRenderingContext2D methods according to the spec.

http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/ says

"Except where otherwise specified, for the 2D context interface,
 any method call with a numeric argument whose value is infinite or a
 NaN value must be ignored."

We might define the annotation to generate this behavior in glue code.
However, at now, I use this workaround way.

1 files changed, 89 insertions, 1 deletions

diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 621bb629df0..37108922fc5 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -8,7 +8,7 @@ use dom::bindings::codegen::Bindings::CanvasRenderingContext2DBinding::CanvasWin
 use dom::bindings::codegen::Bindings::ImageDataBinding::ImageDataMethods;
 use dom::bindings::codegen::UnionTypes::HTMLCanvasElementOrCanvasRenderingContext2D;
 use dom::bindings::codegen::UnionTypes::StringOrCanvasGradientOrCanvasPattern;
-use dom::bindings::error::Error::{IndexSize, TypeError};
+use dom::bindings::error::Error::{IndexSize, NotSupported, TypeError};
 use dom::bindings::error::Fallible;
 use dom::bindings::global::{GlobalRef, GlobalField};
 use dom::bindings::js::{JS, JSRef, LayoutJS, Temporary};
@@ -207,22 +207,44 @@ impl LayoutCanvasRenderingContext2DHelpers for LayoutJS<CanvasRenderingContext2D
     }
 }
 
+// We add a guard to each of methods by the spec:
+// http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/
+//
+// > Except where otherwise specified, for the 2D context interface,
+// > any method call with a numeric argument whose value is infinite or a NaN value must be ignored.
+//
+//  Restricted values are guarded in glue code. Therefore we need not add a guard.
+//
+// FIXME: this behavior should might be generated by some annotattions to idl.
 impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D> {
     fn Canvas(self) -> Temporary<HTMLCanvasElement> {
         Temporary::new(self.canvas)
     }
 
     fn Scale(self, x: f64, y: f64) {
+        if !(x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.transform.set(self.transform.get().scale(x as f32, y as f32));
         self.update_transform()
     }
 
     fn Translate(self, x: f64, y: f64) {
+        if !(x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.transform.set(self.transform.get().translate(x as f32, y as f32));
         self.update_transform()
     }
 
     fn Transform(self, a: f64, b: f64, c: f64, d: f64, e: f64, f: f64) {
+        if !(a.is_finite() && b.is_finite() && c.is_finite() &&
+             d.is_finite() && e.is_finite() && f.is_finite()) {
+            return;
+        }
+
         self.transform.set(self.transform.get().mul(&Matrix2D::new(a as f32,
                                                                    b as f32,
                                                                    c as f32,
@@ -233,6 +255,11 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     }
 
     fn SetTransform(self, a: f64, b: f64, c: f64, d: f64, e: f64, f: f64) {
+        if !(a.is_finite() && b.is_finite() && c.is_finite() &&
+             d.is_finite() && e.is_finite() && f.is_finite()) {
+            return;
+        }
+
         self.transform.set(Matrix2D::new(a as f32,
                                          b as f32,
                                          c as f32,
@@ -243,16 +270,31 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     }
 
     fn FillRect(self, x: f64, y: f64, width: f64, height: f64) {
+        if !(x.is_finite() && y.is_finite() &&
+             width.is_finite() && height.is_finite()) {
+            return;
+        }
+
         let rect = Rect(Point2D(x as f32, y as f32), Size2D(width as f32, height as f32));
         self.renderer.send(CanvasMsg::FillRect(rect)).unwrap();
     }
 
     fn ClearRect(self, x: f64, y: f64, width: f64, height: f64) {
+        if !(x.is_finite() && y.is_finite() &&
+             width.is_finite() && height.is_finite()) {
+            return;
+        }
+
         let rect = Rect(Point2D(x as f32, y as f32), Size2D(width as f32, height as f32));
         self.renderer.send(CanvasMsg::ClearRect(rect)).unwrap();
     }
 
     fn StrokeRect(self, x: f64, y: f64, width: f64, height: f64) {
+        if !(x.is_finite() && y.is_finite() &&
+             width.is_finite() && height.is_finite()) {
+            return;
+        }
+
         let rect = Rect(Point2D(x as f32, y as f32), Size2D(width as f32, height as f32));
         self.renderer.send(CanvasMsg::StrokeRect(rect)).unwrap();
     }
@@ -272,6 +314,9 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     // https://html.spec.whatwg.org/multipage/scripting.html#dom-context-2d-drawimage
     fn DrawImage(self, image: HTMLCanvasElementOrCanvasRenderingContext2D,
                  dx: f64, dy: f64) -> Fallible<()> {
+        if !(dx.is_finite() && dy.is_finite()) {
+            return Ok(());
+        }
 
         // From rules described in the spec:
         // If the sx, sy, sw, and sh arguments are omitted, they must default to 0, 0,
@@ -311,6 +356,10 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     // https://html.spec.whatwg.org/multipage/scripting.html#dom-context-2d-drawimage
     fn DrawImage_(self, image: HTMLCanvasElementOrCanvasRenderingContext2D,
                   dx: f64, dy: f64, dw: f64, dh: f64) -> Fallible<()> {
+        if !(dx.is_finite() && dy.is_finite() &&
+             dw.is_finite() && dh.is_finite()) {
+            return Ok(());
+        }
 
         // From rules described in the spec:
         // If the sx, sy, sw, and sh arguments are omitted, they must default to 0, 0,
@@ -347,6 +396,11 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     fn DrawImage__(self, image: HTMLCanvasElementOrCanvasRenderingContext2D,
                          sx: f64, sy: f64, sw: f64, sh: f64,
                          dx: f64, dy: f64, dw: f64, dh: f64) -> Fallible<()> {
+        if !(sx.is_finite() && sy.is_finite() && sw.is_finite() && sh.is_finite() &&
+             dx.is_finite() && dy.is_finite() && dw.is_finite() && dh.is_finite()) {
+            return Ok(());
+        }
+
         match image {
             HTMLCanvasElementOrCanvasRenderingContext2D::eHTMLCanvasElement(image) => {
                 let canvas = image.root();
@@ -366,19 +420,37 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     }
 
     fn MoveTo(self, x: f64, y: f64) {
+        if !(x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.renderer.send(CanvasMsg::MoveTo(Point2D(x as f32, y as f32))).unwrap();
     }
 
     fn LineTo(self, x: f64, y: f64) {
+        if !(x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.renderer.send(CanvasMsg::LineTo(Point2D(x as f32, y as f32))).unwrap();
     }
 
     fn QuadraticCurveTo(self, cpx: f64, cpy: f64, x: f64, y: f64) {
+        if !(cpx.is_finite() && cpy.is_finite() &&
+             x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.renderer.send(CanvasMsg::QuadraticCurveTo(Point2D(cpx as f32, cpy as f32),
                                                        Point2D(x as f32, y as f32))).unwrap();
     }
 
     fn BezierCurveTo(self, cp1x: f64, cp1y: f64, cp2x: f64, cp2y: f64, x: f64, y: f64) {
+        if !(cp1x.is_finite() && cp1y.is_finite() && cp2x.is_finite() && cp2y.is_finite() &&
+             x.is_finite() && y.is_finite()) {
+            return;
+        }
+
         self.renderer.send(CanvasMsg::BezierCurveTo(Point2D(cp1x as f32, cp1y as f32),
                                                     Point2D(cp2x as f32, cp2y as f32),
                                                     Point2D(x as f32, y as f32))).unwrap();
@@ -463,6 +535,10 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     }
 
     fn CreateImageData(self, sw: f64, sh: f64) -> Fallible<Temporary<ImageData>> {
+        if !(sw.is_finite() && sh.is_finite()) {
+            return Err(NotSupported);
+        }
+
         if sw == 0.0 || sh == 0.0 {
             return Err(IndexSize)
         }
@@ -491,6 +567,12 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
     }
 
     fn PutImageData(self, imagedata: JSRef<ImageData>, dx: Finite<f64>, dy: Finite<f64>) {
+        // XXX:
+        // By the spec: http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/#dom-context-2d-putimagedata
+        // "If any of the arguments to the method are infinite or NaN, the method must throw a NotSupportedError exception"
+        // But this arguments are stricted value, so if they are not finite values,
+        // they will be TypeError by WebIDL spec before call this methods.
+
         let data = imagedata.get_data_array(&self.global.root().r());
         let image_data_rect = Rect(Point2D(dx.to_i32().unwrap(), dy.to_i32().unwrap()), imagedata.get_size());
         let dirty_rect = None;
@@ -499,6 +581,12 @@ impl<'a> CanvasRenderingContext2DMethods for JSRef<'a, CanvasRenderingContext2D>
 
     fn PutImageData_(self, imagedata: JSRef<ImageData>, dx: Finite<f64>, dy: Finite<f64>,
                      dirtyX: Finite<f64>, dirtyY: Finite<f64>, dirtyWidth: Finite<f64>, dirtyHeight: Finite<f64>) {
+        // XXX:
+        // By the spec: http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/#dom-context-2d-putimagedata
+        // "If any of the arguments to the method are infinite or NaN, the method must throw a NotSupportedError exception"
+        // But this arguments are stricted value, so if they are not finite values,
+        // they will be TypeError by WebIDL spec before call this methods.
+
         let data = imagedata.get_data_array(&self.global.root().r());
         let image_data_rect = Rect(Point2D(dx.to_i32().unwrap(), dy.to_i32().unwrap()),
                                    Size2D(imagedata.Width().to_i32().unwrap(),