added spec link for type mapping
Hi. added some of the spec links, that i could understand from the spec. Please mention if anything else needs to be added.
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Fix uses of JS<T> as a type on the stack
`JS<T>` belongs on the heap, and only on the heap. This is a collection of fixes so that code uses either `Root<T>` or `&T` to pass around garbage-collected pointers.
Ideally, we could completely ban constructing a `JS<T>` outside of constructor functions, but we aren't quite there yet.
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get() must always return a rooted value, because we have no way of
ensuring the value won't be invalidated. set() takes an &T because it's
convenient; there isn't any need to expose JS<T>.
Given codegen now generates the various TypeId enums, it seems pointless to
still have to write their respective values in every DOM struct inheriting from
Node just to set the initial IS_IN_DOC flag in Document and IN_ENABLED_STATE in
form controls.
Introduce DOMClass::heap_size_of
It holds a function pointer to the HeapSizeOf::heap_size_of_children()
implementation corresponding to that IDL interface.
This removes the need for a clumsly TypeId-based match expression in the
former heap_size_of_eventtarget() function.
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It holds a function pointer to the HeapSizeOf::heap_size_of_children()
implementation corresponding to that IDL interface.
This removes the need for a clumsly TypeId-based match expression in the
former heap_size_of_eventtarget() function.
Changed dom_class type to Option<&'static DOMClass> to fix#7942
I have a feeling that converting `Option<&T>` to `*const libc::c_void` could be less explicit.
Was there any way to do it shorter?
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Fix spurious rebuilds of the script crate
The script crate currently has a build script, and Cargo will consider all files
in the script crate as inputs to the build script as it otherwise doesn't know
[what the input files are][cargo-1162]. This means that if any file in the
source tree of the script crate changes (or is created) then Cargo will think it
needs to re-run the build script and rebuild the crate.
[cargo-1162]: https://github.com/rust-lang/cargo/issues/1162
The build script of the script crate is invoking python, and consequently Python
is generating some bytecode files in the source tree. On the second build of
Servo, Cargo will see these new files, think that something has changed, and
will re-run the build script of the script crate.
This change passes the `-B` flag to python to avoid generating these bytecode
files, which should avoid tampering with the source tree and appease Cargo by
ensuring that it doesn't get rebuilt.
---
As a helpful tip to if this comes up again, this was discovered by using the
changes in rust-lang/cargo@c447e9d plus the change in rust-lang/cargo#2044. Once
`RUST_LOG` was set to `cargo::ops::cargo_rustc::fingerprint=info`, the second
run of `./mach build` printed out:
```
precalculated components have changed:
1444364448.000000000s (/build/servo/components/script/dom/bindings/codegen/parser/WebIDL.pyc) !=
1444364235.000000000s (/build/servo/components/script/document_loader.rs)
```
Which should help easily diagnose these kinds of problems in the future!
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