- Instead of storing a pointer whose type refers to the specific
subclass of `BaseObject`, just store a `BaseObject*` directly.
This means in particular that one can cast to classes along
the way of the inheritance chain without issues, and that
`BaseObject*` no longer needs to be the first superclass
in the case of multiple inheritance.
In particular, this renders hack-y solutions to this problem (like
ddc19be6de) obsolete and addresses
a `TODO` comment of mine.
- Move wrapping/unwrapping methods to the `BaseObject` class.
We use these almost exclusively for `BaseObject`s, and I hope
that this gives a better idea of how (and for what) these are used
in our code.
- Perform initialization/deinitialization of the internal field
in the `BaseObject*` constructor/destructor. This makes the code
a bit more obviously correct, avoids explicit calls for this
in subclass constructors, and in particular allows us to avoid
crash situations when we previously called `ClearWrap()`
during GC.
This also means that we enforce that the object passed to the
`BaseObject` constructor needs to have an internal field.
This is the only reason for the test change.
- Change the signature of `MakeWeak()` to not require a pointer
argument. Previously, this would always have been the same
as `this`, and no other value made sense. Also, the parameter
was something that I personally found somewhat confusing
when becoming familiar with Node’s code.
- Add a `TODO` comment that motivates switching to real inheritance
for the JS types we expose from the native side. This patch
brings us a lot closer to being able to do that.
- Some less significant drive-by cleanup.
Since we *effectively* already store the `BaseObject*` pointer
anyway since ddc19be6de, I do not
think that this is going to have any impact on diagnostic tooling.
Fixes: https://github.com/nodejs/node/issues/18897
PR-URL: https://github.com/nodejs/node/pull/20455
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
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