Auto merge of #22495 - maharsh312:master, r=jdm

OffscreenCanvas API

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Initial Steps for OffscreenCanvas API are done in this commit.

r? @jdm
---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #14627 (GitHub issue number if applicable)

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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components/script/dom/mod.rs

@@ -407,6 +407,8 @@ pub mod nodeiterator;
 pub mod nodelist;
 pub mod offlineaudiocompletionevent;
 pub mod offlineaudiocontext;
+pub mod offscreencanvas;
+pub mod offscreencanvasrenderingcontext2d;
 pub mod oscillatornode;
 pub mod pagetransitionevent;
 pub mod paintrenderingcontext2d;

components/script/dom/offscreencanvas.rs

@@ -0,0 +1,146 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::codegen::Bindings::OffscreenCanvasBinding::{
+    OffscreenCanvasMethods, OffscreenRenderingContext, Wrap as OffscreenCanvasWrap,
+};
+use crate::dom::bindings::error::Fallible;
+use crate::dom::bindings::reflector::reflect_dom_object;
+use crate::dom::bindings::reflector::DomObject;
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::eventtarget::EventTarget;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::htmlcanvaselement::HTMLCanvasElement;
+use crate::dom::offscreencanvasrenderingcontext2d::OffscreenCanvasRenderingContext2D;
+use dom_struct::dom_struct;
+use euclid::Size2D;
+use js::jsapi::JSContext;
+use js::rust::HandleValue;
+use ref_filter_map;
+use std::cell::Cell;
+use std::cell::Ref;
+
+#[must_root]
+#[derive(Clone, JSTraceable, MallocSizeOf)]
+pub enum OffscreenCanvasContext {
+    OffscreenContext2d(Dom<OffscreenCanvasRenderingContext2D>),
+    //WebGL(Dom<WebGLRenderingContext>),
+    //WebGL2(Dom<WebGL2RenderingContext>),
+}
+
+#[dom_struct]
+pub struct OffscreenCanvas {
+    eventtarget: EventTarget,
+    height: Cell<u64>,
+    width: Cell<u64>,
+    context: DomRefCell<Option<OffscreenCanvasContext>>,
+    placeholder: Option<Dom<HTMLCanvasElement>>,
+}
+
+impl OffscreenCanvas {
+    pub fn new_inherited(
+        height: u64,
+        width: u64,
+        placeholder: Option<&HTMLCanvasElement>,
+    ) -> OffscreenCanvas {
+        OffscreenCanvas {
+            eventtarget: EventTarget::new_inherited(),
+            height: Cell::new(height),
+            width: Cell::new(width),
+            context: DomRefCell::new(None),
+            placeholder: placeholder.map(Dom::from_ref),
+        }
+    }
+
+    pub fn new(
+        global: &GlobalScope,
+        height: u64,
+        width: u64,
+        placeholder: Option<&HTMLCanvasElement>,
+    ) -> DomRoot<OffscreenCanvas> {
+        reflect_dom_object(
+            Box::new(OffscreenCanvas::new_inherited(height, width, placeholder)),
+            global,
+            OffscreenCanvasWrap,
+        )
+    }
+
+    pub fn Constructor(
+        global: &GlobalScope,
+        height: u64,
+        width: u64,
+    ) -> Fallible<DomRoot<OffscreenCanvas>> {
+        let offscreencanvas = OffscreenCanvas::new(global, height, width, None);
+        Ok(offscreencanvas)
+    }
+
+    pub fn get_size(&self) -> Size2D<u64> {
+        Size2D::new(self.Width(), self.Height())
+    }
+
+    pub fn context(&self) -> Option<Ref<OffscreenCanvasContext>> {
+        ref_filter_map::ref_filter_map(self.context.borrow(), |ctx| ctx.as_ref())
+    }
+
+    #[allow(unsafe_code)]
+    fn get_or_init_2d_context(&self) -> Option<DomRoot<OffscreenCanvasRenderingContext2D>> {
+        if let Some(ctx) = self.context() {
+            return match *ctx {
+                OffscreenCanvasContext::OffscreenContext2d(ref ctx) => Some(DomRoot::from_ref(ctx)),
+            };
+        }
+        let size = self.get_size();
+        let context = OffscreenCanvasRenderingContext2D::new(&self.global(), self, size);
+        *self.context.borrow_mut() = Some(OffscreenCanvasContext::OffscreenContext2d(
+            Dom::from_ref(&*context),
+        ));
+        Some(context)
+    }
+}
+
+impl OffscreenCanvasMethods for OffscreenCanvas {
+    // https://html.spec.whatwg.org/multipage/#dom-offscreencanvas-getcontext
+    #[allow(unsafe_code)]
+    unsafe fn GetContext(
+        &self,
+        _cx: *mut JSContext,
+        id: DOMString,
+        _options: HandleValue,
+    ) -> Option<OffscreenRenderingContext> {
+        match &*id {
+            "2d" => self
+                .get_or_init_2d_context()
+                .map(OffscreenRenderingContext::OffscreenCanvasRenderingContext2D),
+            /*"webgl" | "experimental-webgl" => self
+                .get_or_init_webgl_context(cx, options)
+                .map(OffscreenRenderingContext::WebGLRenderingContext),
+            "webgl2" | "experimental-webgl2" => self
+                .get_or_init_webgl2_context(cx, options)
+                .map(OffscreenRenderingContext::WebGL2RenderingContext),*/
+            _ => None,
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-offscreencanvas-width
+    fn Width(&self) -> u64 {
+        return self.width.get();
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-offscreencanvas-width
+    fn SetWidth(&self, value: u64) {
+        self.width.set(value);
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-offscreencanvas-height
+    fn Height(&self) -> u64 {
+        return self.height.get();
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-offscreencanvas-height
+    fn SetHeight(&self, value: u64) {
+        self.height.set(value);
+    }
+}

components/script/dom/offscreencanvasrenderingcontext2d.rs

@@ -0,0 +1,55 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::codegen::Bindings::OffscreenCanvasRenderingContext2DBinding;
+use crate::dom::bindings::codegen::Bindings::OffscreenCanvasRenderingContext2DBinding::OffscreenCanvasRenderingContext2DMethods;
+use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::offscreencanvas::OffscreenCanvas;
+use dom_struct::dom_struct;
+use euclid::Size2D;
+
+#[dom_struct]
+pub struct OffscreenCanvasRenderingContext2D {
+    reflector_: Reflector,
+    canvas: Option<Dom<OffscreenCanvas>>,
+}
+
+impl OffscreenCanvasRenderingContext2D {
+    pub fn new_inherited(
+        _global: &GlobalScope,
+        canvas: Option<&OffscreenCanvas>,
+        _size: Size2D<u64>,
+    ) -> OffscreenCanvasRenderingContext2D {
+        OffscreenCanvasRenderingContext2D {
+            reflector_: Reflector::new(),
+            canvas: canvas.map(Dom::from_ref),
+        }
+    }
+
+    pub fn new(
+        _global: &GlobalScope,
+        canvas: &OffscreenCanvas,
+        _size: Size2D<u64>,
+    ) -> DomRoot<OffscreenCanvasRenderingContext2D> {
+        let boxed = Box::new(OffscreenCanvasRenderingContext2D::new_inherited(
+            _global,
+            Some(canvas),
+            _size,
+        ));
+        reflect_dom_object(
+            boxed,
+            _global,
+            OffscreenCanvasRenderingContext2DBinding::Wrap,
+        )
+    }
+}
+
+impl OffscreenCanvasRenderingContext2DMethods for OffscreenCanvasRenderingContext2D {
+    // https://html.spec.whatwg.org/multipage/offscreencontext2d-canvas
+    fn Canvas(&self) -> DomRoot<OffscreenCanvas> {
+        DomRoot::from_ref(self.canvas.as_ref().expect("No canvas."))
+    }
+}

components/script/dom/webidls/OffscreenCanvas.webidl

@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#the-offscreencanvas-interface
+typedef (OffscreenCanvasRenderingContext2D or WebGLRenderingContext or WebGL2RenderingContext)
+OffscreenRenderingContext;
+
+dictionary ImageEncodeOptions {
+  DOMString type = "image/png";
+  unrestricted double quality = 1.0;
+};
+
+//enum OffscreenRenderingContextId { "2d", "webgl", "webgl2" };
+
+[Constructor([EnforceRange] unsigned long long width, [EnforceRange] unsigned long long height),
+Exposed=(Window,Worker)/*, Transferable*/, Pref="dom.offscreen_canvas.enabled"]
+interface OffscreenCanvas : EventTarget {
+  attribute /*[EnforceRange]*/ unsigned long long width;
+  attribute /*[EnforceRange]*/ unsigned long long height;
+
+  OffscreenRenderingContext? getContext(DOMString contextId, optional any options = null);
+  //ImageBitmap transferToImageBitmap();
+  //Promise<Blob> convertToBlob(optional ImageEncodeOptions options);
+};

components/script/dom/webidls/OffscreenCanvasRenderingContext2D.webidl

@@ -0,0 +1,26 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#the-offscreen-2d-rendering-context
+[Exposed=(Window,Worker), Pref="dom.offscreen_canvas.enabled"]
+interface OffscreenCanvasRenderingContext2D {
+  //void commit();
+  readonly attribute OffscreenCanvas canvas;
+};
+
+//OffscreenCanvasRenderingContext2D includes CanvasState;
+//OffscreenCanvasRenderingContext2D includes CanvasTransform;
+//OffscreenCanvasRenderingContext2D includes CanvasCompositing;
+//OffscreenCanvasRenderingContext2D includes CanvasImageSmoothing;
+//OffscreenCanvasRenderingContext2D includes CanvasFillStrokeStyles;
+//OffscreenCanvasRenderingContext2D includes CanvasShadowStyles;
+//OffscreenCanvasRenderingContext2D includes CanvasFilters;
+//OffscreenCanvasRenderingContext2D includes CanvasRect;
+//OffscreenCanvasRenderingContext2D includes CanvasDrawPath;
+//OffscreenCanvasRenderingContext2D includes CanvasText;
+//OffscreenCanvasRenderingContext2D includes CanvasDrawImage;
+//OffscreenCanvasRenderingContext2D includes CanvasImageData;
+//OffscreenCanvasRenderingContext2D includes CanvasPathDrawingStyles;
+//OffscreenCanvasRenderingContext2D includes CanvasTextDrawingStyles;
+//OffscreenCanvasRenderingContext2D includes CanvasPath;

resources/prefs.json

@@ -9,6 +9,7 @@
   "dom.microdata.testing.enabled": true,
   "dom.mouseevent.which.enabled": false,
   "dom.mutation_observer.enabled": true,
+  "dom.offscreen_canvas.enabled": false,
   "dom.permissions.enabled": false,
   "dom.permissions.testing.allowed_in_nonsecure_contexts": false,
   "dom.serviceworker.timeout_seconds": 60,

tests/wpt/include.ini

@@ -97,6 +97,8 @@ skip: true
   skip: false
 [navigation-timing]
   skip: false
+[offscreen-canvas]
+  skip: false
 [old-tests]
   skip: true
   [submission]

tests/wpt/metadata/css/CSS2/positioning/abspos-float-with-inline-container.html.ini

@@ -1,2 +1,2 @@
 [abspos-float-with-inline-container.html]
-  expected: FAIL
+  expected: TIMEOUT

tests/wpt/metadata/css/CSS2/text/white-space-002.xht.ini

@@ -0,0 +1,2 @@
+[white-space-002.xht]
+  expected: FAIL

tests/wpt/metadata/css/CSS2/visudet/line-height-204.html.ini

@@ -0,0 +1,2 @@
+[line-height-204.html]
+  expected: FAIL

tests/wpt/metadata/css/compositing/mix-blend-mode/mix-blend-mode-paragraph.html.ini

@@ -0,0 +1,2 @@
+[mix-blend-mode-paragraph.html]
+  expected: FAIL

tests/wpt/metadata/css/css-backgrounds/background-repeat/background-repeat-round-roundup.xht.ini

@@ -0,0 +1,2 @@
+[background-repeat-round-roundup.xht]
+  expected: FAIL

tests/wpt/metadata/css/css-fonts/variations/at-font-face-font-matching.html.ini

@@ -182,9 +182,6 @@
   [Matching font-style: 'oblique 20deg' should prefer 'oblique 40deg 50deg' over 'oblique 10deg']
     expected: FAIL
 
-  [Matching font-style: 'oblique 20deg' should prefer 'oblique 10deg' over 'italic']
-    expected: FAIL
-
   [Matching font-style: 'oblique 20deg' should prefer 'oblique 0deg' over 'oblique -50deg -20deg']
     expected: FAIL
 
@@ -248,9 +245,6 @@
   [Matching font-style: 'oblique 21deg' should prefer 'oblique 21deg' over 'oblique 30deg 60deg']
     expected: FAIL
 
-  [Matching font-style: 'oblique 21deg' should prefer 'oblique 40deg 50deg' over 'oblique 20deg']
-    expected: FAIL
-
   [Matching font-style: 'oblique -10deg' should prefer 'oblique -5deg' over 'oblique -1deg 0deg']
     expected: FAIL
 

tests/wpt/metadata/css/css-fonts/variations/font-weight-matching.html.ini

@@ -5,9 +5,6 @@
   [Test @font-face matching for weight 470]
     expected: FAIL
 
-  [Test @font-face matching for weight 500]
-    expected: FAIL
-
   [Test @font-face matching for weight 600]
     expected: FAIL
 

tests/wpt/metadata/css/css-text/word-break/word-break-keep-all-006.html.ini

@@ -0,0 +1,2 @@
+[word-break-keep-all-006.html]
+  expected: FAIL

tests/wpt/metadata/css/css-transitions/transitions-animatable-properties-01.html.ini

@@ -74,3 +74,6 @@
   [opacity end]
     expected: FAIL
 
+  [border-top-width end]
+    expected: FAIL
+

tests/wpt/metadata/custom-elements/parser/parser-sets-attributes-and-children.html.ini

@@ -1,2 +1,2 @@
 [parser-sets-attributes-and-children.html]
-  expected: TIMEOUT
+  expected: CRASH

tests/wpt/metadata/encoding/single-byte-decoder.html.ini

@@ -55,7 +55,7 @@
     expected: FAIL
 
   [windows-1252: iso_8859-1:1987 (XMLHttpRequest)]
-    expected: TIMEOUT
+    expected: FAIL
 
   [windows-1254: iso_8859-9:1989 (XMLHttpRequest)]
     expected: TIMEOUT