Auto merge of #22648 - collares:ChannelSplitterNode, r=Manishearth

Implement DOM APIs for ChannelSplitterNode

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Based on #21591. Fixes #21558. I tried to update the expected results for WPT using "./mach update-wpt"; let me know if I got something wrong.

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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 the second half of #21558

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- [x] There are web-platform-tests tests for these changes
- [ ] These changes do not require tests because ___

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components/script/dom/audionode.rs

@@ -237,9 +237,10 @@ impl AudioNodeMethods for AudioNode {
                 }
             },
             EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
-                if value != 1 {
-                    return Err(Error::InvalidState);
-                }
+                return Err(Error::InvalidState);
+            },
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelSplitterNode) => {
+                return Err(Error::InvalidState);
             },
             // XXX We do not support any of the other AudioNodes with
             // constraints yet. Add more cases here as we add support
@@ -280,9 +281,10 @@ impl AudioNodeMethods for AudioNode {
                 }
             },
             EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
-                if value != ChannelCountMode::Explicit {
-                    return Err(Error::InvalidState);
-                }
+                return Err(Error::InvalidState);
+            },
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelSplitterNode) => {
+                return Err(Error::InvalidState);
             },
             // XXX We do not support any of the other AudioNodes with
             // constraints yet. Add more cases here as we add support
@@ -301,14 +303,22 @@ impl AudioNodeMethods for AudioNode {
     }
 
     // https://webaudio.github.io/web-audio-api/#dom-audionode-channelinterpretation
-    fn SetChannelInterpretation(&self, value: ChannelInterpretation) {
+    fn SetChannelInterpretation(&self, value: ChannelInterpretation) -> ErrorResult {
         // Channel interpretation mode has no effect for nodes with no inputs.
         if self.number_of_inputs == 0 {
-            return;
+            return Ok(());
         }
 
+        match self.upcast::<EventTarget>().type_id() {
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelSplitterNode) => {
+                return Err(Error::InvalidState);
+            },
+            _ => (),
+        };
+
         self.channel_interpretation.set(value);
         self.message(AudioNodeMessage::SetChannelInterpretation(value.into()));
+        Ok(())
     }
 }
 

components/script/dom/baseaudiocontext.rs

@@ -22,6 +22,7 @@ use crate::dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeErro
 use crate::dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeSuccessCallback;
 use crate::dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::BiquadFilterOptions;
 use crate::dom::bindings::codegen::Bindings::ChannelMergerNodeBinding::ChannelMergerOptions;
+use crate::dom::bindings::codegen::Bindings::ChannelSplitterNodeBinding::ChannelSplitterOptions;
 use crate::dom::bindings::codegen::Bindings::GainNodeBinding::GainOptions;
 use crate::dom::bindings::codegen::Bindings::OscillatorNodeBinding::OscillatorOptions;
 use crate::dom::bindings::codegen::Bindings::PannerNodeBinding::PannerOptions;
@@ -33,6 +34,7 @@ use crate::dom::bindings::reflector::DomObject;
 use crate::dom::bindings::root::{DomRoot, MutNullableDom};
 use crate::dom::biquadfilternode::BiquadFilterNode;
 use crate::dom::channelmergernode::ChannelMergerNode;
+use crate::dom::channelsplitternode::ChannelSplitterNode;
 use crate::dom::domexception::{DOMErrorName, DOMException};
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::gainnode::GainNode;
@@ -360,6 +362,13 @@ impl BaseAudioContextMethods for BaseAudioContext {
         ChannelMergerNode::new(&self.global().as_window(), &self, &opts)
     }
 
+    /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createchannelsplitter
+    fn CreateChannelSplitter(&self, count: u32) -> Fallible<DomRoot<ChannelSplitterNode>> {
+        let mut opts = ChannelSplitterOptions::empty();
+        opts.numberOfOutputs = count;
+        ChannelSplitterNode::new(&self.global().as_window(), &self, &opts)
+    }
+
     /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createbuffer
     fn CreateBuffer(
         &self,

components/script/dom/channelsplitternode.rs

@@ -0,0 +1,80 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::audionode::{AudioNode, MAX_CHANNEL_COUNT};
+use crate::dom::baseaudiocontext::BaseAudioContext;
+use crate::dom::bindings::codegen::Bindings::AudioNodeBinding::{
+    ChannelCountMode, ChannelInterpretation,
+};
+use crate::dom::bindings::codegen::Bindings::ChannelSplitterNodeBinding::{
+    self, ChannelSplitterOptions,
+};
+use crate::dom::bindings::error::{Error, Fallible};
+use crate::dom::bindings::reflector::reflect_dom_object;
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::window::Window;
+use dom_struct::dom_struct;
+use servo_media::audio::node::AudioNodeInit;
+
+#[dom_struct]
+pub struct ChannelSplitterNode {
+    node: AudioNode,
+}
+
+impl ChannelSplitterNode {
+    #[allow(unrooted_must_root)]
+    pub fn new_inherited(
+        _: &Window,
+        context: &BaseAudioContext,
+        options: &ChannelSplitterOptions,
+    ) -> Fallible<ChannelSplitterNode> {
+        if options.numberOfOutputs < 1 || options.numberOfOutputs > MAX_CHANNEL_COUNT {
+            return Err(Error::IndexSize);
+        }
+
+        let node_options = options.parent.unwrap_or(
+            options.numberOfOutputs,
+            ChannelCountMode::Explicit,
+            ChannelInterpretation::Discrete,
+        );
+
+        if node_options.count != options.numberOfOutputs ||
+            node_options.mode != ChannelCountMode::Explicit ||
+            node_options.interpretation != ChannelInterpretation::Discrete
+        {
+            return Err(Error::InvalidState);
+        }
+
+        let node = AudioNode::new_inherited(
+            AudioNodeInit::ChannelSplitterNode,
+            context,
+            node_options,
+            1,                       // inputs
+            options.numberOfOutputs, // outputs
+        )?;
+        Ok(ChannelSplitterNode { node })
+    }
+
+    #[allow(unrooted_must_root)]
+    pub fn new(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &ChannelSplitterOptions,
+    ) -> Fallible<DomRoot<ChannelSplitterNode>> {
+        let node = ChannelSplitterNode::new_inherited(window, context, options)?;
+        Ok(reflect_dom_object(
+            Box::new(node),
+            window,
+            ChannelSplitterNodeBinding::Wrap,
+        ))
+    }
+
+    pub fn Constructor(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &ChannelSplitterOptions,
+    ) -> Fallible<DomRoot<ChannelSplitterNode>> {
+        ChannelSplitterNode::new(window, context, options)
+    }
+}

components/script/dom/mod.rs

@@ -244,6 +244,7 @@ pub mod canvasgradient;
 pub mod canvaspattern;
 pub mod canvasrenderingcontext2d;
 pub mod channelmergernode;
+pub mod channelsplitternode;
 pub mod characterdata;
 pub mod client;
 pub mod closeevent;

components/script/dom/webidls/AudioNode.webidl

@@ -57,5 +57,6 @@ interface AudioNode : EventTarget {
   attribute unsigned long channelCount;
   [SetterThrows]
   attribute ChannelCountMode channelCountMode;
+  [SetterThrows]
   attribute ChannelInterpretation channelInterpretation;
 };

components/script/dom/webidls/BaseAudioContext.webidl

@@ -45,7 +45,7 @@ interface BaseAudioContext : EventTarget {
   [Throws] PannerNode createPanner();
   // StereoPannerNode createStereoPanner();
   // ConvolverNode createConvolver();
-  // ChannelSplitterNode createChannelSplitter(optional unsigned long numberOfOutputs = 6);
+  [Throws] ChannelSplitterNode createChannelSplitter(optional unsigned long numberOfOutputs = 6);
   [Throws] ChannelMergerNode createChannelMerger(optional unsigned long numberOfInputs = 6);
   // DynamicsCompressorNode createDynamicsCompressor();
   [Throws]  OscillatorNode createOscillator();

components/script/dom/webidls/ChannelSplitterNode.webidl

@@ -0,0 +1,16 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+/*
+ * The origin of this IDL file is
+ * https://webaudio.github.io/web-audio-api/#channelsplitternode
+ */
+
+dictionary ChannelSplitterOptions : AudioNodeOptions {
+  unsigned long numberOfOutputs = 6;
+};
+
+[Exposed=Window,
+ Constructor (BaseAudioContext context, optional ChannelSplitterOptions options)]
+interface ChannelSplitterNode : AudioNode {
+};