This commit adds a new tab to the Settings modal: Debugging
This new tab has the append component stacks feature and a new one: break on warn
This new feature adds a debugger statement into the console override
* DevTools console override handles new component stack format
DevTools does not attempt to mimic the default browser console format for its component stacks but it does properly detect the new format for Chrome, Firefox, and Safari.
Some of our internal reconciler types have leaked into other packages.
Usually, these types are treated as opaque; we don't read and write
to its fields. This is good.
However, the type is often passed back to a reconciler method. For
example, React DOM creates a FiberRoot with `createContainer`, then
passes that root to `updateContainer`. It doesn't do anything with the
root except pass it through, but because `updateContainer` expects a
full FiberRoot, React DOM is still coupled to all its fields.
I don't know if there's an idiomatic way to handle this in Flow. Opaque
types are simlar, but those only work within a single file. AFAIK,
there's no way to use a package as the boundary for opaqueness.
The immediate problem this presents is that the reconciler refactor will
involve changes to our internal data structures. I don't want to have to
fork every single package that happens to pass through a Fiber or
FiberRoot, or access any one of its fields. So my current plan is to
share the same Flow type across both forks. The shared type will be a
superset of each implementation's type, e.g. Fiber will have both an
`expirationTime` field and a `lanes` field. The implementations will
diverge, but not the types.
To do this, I lifted the type definitions into a separate module.
* Enable prefer-const rule
Stylistically I don't like this but Closure Compiler takes advantage of
this information.
* Auto-fix lints
* Manually fix the remaining callsites
Rick Hanlon
Brian Vaughn
Andrew Clark
Sebastian Markbåge
Alex Rohleder