Unify the task source and task canceller API

I moved away from the `Window` struct all the logic to handle task
sources, into a new struct called `TaskManager`. In a happy world, I'd
be able to just have there two functions, of the types:

```rust
fn task_source<T: TaskSource>(&self, name: TaskSourceName) -> Box<T>
fn task_source_with_canceller<T: TaskSource>(&self, name: TaskSourceName)
  -> (Box<T>, TaskSourceCanceller)
```

And not so much duplicated code. However, because TaskSource can't be a
trait object (because it has generic type parameters), that's not
possible. Instead, I decided to reduce duplicated logic through macros.

For reasons[1], I have to pass both the name of the function with
canceller and the name of the function without, as I'm not able to
concatenate them in the macro itself. I could probably use
`concat_idents` to create both types already defined and reduce the
amount of arguments by one, but that macro is nightly only. At the same
time, not being able to declare macros inside `impl` forces me to pass
`self` as an argument.

All this makes this solution more verbose than it would be ideally. It
does reduce duplication, but it doesn't reduce the size of the file.

[1](https://github.com/rust-lang/rust/issues/29599)
This commit is contained in:
Agustin Chiappe Berrini 2018-09-24 19:31:59 -04:00
parent 14bc8ab754
commit 75eb94afca
26 changed files with 362 additions and 252 deletions

View file

@ -40,7 +40,7 @@ use crate::dom::oscillatornode::OscillatorNode;
use crate::dom::pannernode::PannerNode;
use crate::dom::promise::Promise;
use crate::dom::window::Window;
use crate::task_source::{TaskSource, TaskSourceName};
use crate::task_source::TaskSource;
use dom_struct::dom_struct;
use js::rust::CustomAutoRooterGuard;
use js::typedarray::ArrayBuffer;
@ -213,7 +213,7 @@ impl BaseAudioContext {
pub fn resume(&self) {
let global = self.global();
let window = global.as_window();
let task_source = window.dom_manipulation_task_source();
let task_source = window.task_manager().dom_manipulation_task_source();
let this = Trusted::new(self);
// Set the rendering thread state to 'running' and start
// rendering the audio graph.
@ -227,7 +227,7 @@ impl BaseAudioContext {
if this.state.get() != AudioContextState::Running {
this.state.set(AudioContextState::Running);
let window = DomRoot::downcast::<Window>(this.global()).unwrap();
window.dom_manipulation_task_source().queue_simple_event(
window.task_manager().dom_manipulation_task_source().queue_simple_event(
this.upcast(),
atom!("statechange"),
&window
@ -428,10 +428,12 @@ impl BaseAudioContextMethods for BaseAudioContext {
let decoded_audio__ = decoded_audio.clone();
let this = Trusted::new(self);
let this_ = this.clone();
let task_source = window.dom_manipulation_task_source();
let task_source_ = window.dom_manipulation_task_source();
let canceller = window.task_canceller(TaskSourceName::DOMManipulation);
let canceller_ = window.task_canceller(TaskSourceName::DOMManipulation);
let (task_source, canceller) = window
.task_manager()
.dom_manipulation_task_source_with_canceller();
let (task_source_, canceller_) = window
.task_manager()
.dom_manipulation_task_source_with_canceller();
let callbacks = AudioDecoderCallbacks::new()
.ready(move |channel_count| {
decoded_audio