* Lazify Blocks
Blocks now initialize lazily.
* Initialize Blocks eagerly in ChildFiber
This is for the case when it's a new Block that hasn't yet initialized.
We need to first initialize it to see what "render function" it resolves
to so that we can use that in our comparison.
* Remove extra import type line
* This type is all wrong and nothing cares because it's all any
* Refine Flow types of Lazy Components
We can type each condition.
* Remove _ctor field from Lazy components
This field is not needed because it's only used before we've initialized,
and we don't have anything else to store before we've initialized.
* Check for _ctor in case it's an older isomorphic that created it
We try not to break across minors but it's no guarantee.
* Move types and constants from shared to isomorphic
The "react" package owns the data structure of the Lazy component. It
creates it and decides how any downstream renderer may use it.
* Move constants to shared
Apparently we can't depend on react/src/ because the whole package is
considered "external" as far as rollup is concerned.
* Update Flow to 0.84
* Fix violations
* Use inexact object syntax in files from fbsource
* Fix warning extraction to use a modern parser
* Codemod inexact objects to new syntax
* Tighten types that can be exact
* Revert unintentional formatting changes from codemod
* Replace all warning/lowPriWarning with console calls
* Replace console.warn/error with a custom wrapper at build time
* Fail the build for console.error/warn() where we can't read the stack
* prep for codemod
* prep warnings
* rename lint rules
* codemod for ifs
* shim www functions
* Handle more cases in the transform
* Thanks De Morgan
* Run the codemod
* Delete the transform
* Fix up confusing conditions manually
* Fix up www shims to match expected API
* Also check for low-pri warning in the lint rule
Provides partial support for React.lazy() components from the existing PartialRenderer server-side renderer.
Lazy components which are already resolved (or rejected), perhaps with something like `react-ssr-prepass`, can be continued into synchronously. If they have not yet been initialized, they'll be initialized before checking, opening the possibility to exploit this capability with a babel transform. If they're pending (which will typically be the case for a just initialized async ctor) then the existing invariant continues to be thrown.
* Introduce elementType field
This will be used to store the wrapped type of an element. E.g. pure and
lazy.
The existing type field will be used for the unwrapped type within them.
* Store the unwrapped type on the type field of lazy components
* Use the raw tags for lazy components
Instead, we check if the elementType and type are equal to test if
we need to resolve props. This is slightly slower in the normal case
but will yield less code and branching.
* Clean up lazy branches
* Collapse work tag numbering
* Split IndeterminateComponent out from Lazy
This way we don't have to check the type in a hacky way in the
indeterminate path. Also, lets us deal with lazy that resolves to
indeterminate and such.
* Missing clean up in rebase
Removes support for using arbitrary promises as the type of a React
element. Instead, promises must be wrapped in React.lazy. This gives us
flexibility later if we need to change the protocol.
The reason is that promises do not provide a way to call their
constructor multiple times. For example:
const promiseForA = new Promise(resolve => {
fetchA(a => resolve(a));
});
Given a reference to `promiseForA`, there's no way to call `fetchA`
again. Calling `then` on the promise doesn't run the constructor again;
it only attaches another listener.
In the future we will likely introduce an API like `React.eager` that
is similar to `lazy` but eagerly calls the constructor. That gives us
the ability to call the constructor multiple times. E.g. to increase
the priority, or to retry if the first operation failed.
* Accept promise as element type
On the initial render, the element will suspend as if a promise were
thrown from inside the body of the unresolved component. Siblings should
continue rendering and if the parent is a Placeholder, the promise
should be captured by that Placeholder.
When the promise resolves, rendering resumes. If the resolved value
has a `default` property, it is assumed to be the default export of
an ES module, and we use that as the component type. If it does not have
a `default` property, we use the resolved value itself.
The resolved value is stored as an expando on the promise/thenable.
* Use special types of work for lazy components
Because reconciliation is a hot path, this adds ClassComponentLazy,
FunctionalComponentLazy, and ForwardRefLazy as special types of work.
The other types are not supported, but wouldn't be placed into a
separate module regardless.
* Resolve defaultProps for lazy types
* Remove some calls to isContextProvider
isContextProvider checks the fiber tag, but it's typically called after
we've already refined the type of work. We should get rid of it. I
removed some of them in the previous commit, and deleted a few more
in this one. I left a few behind because the remaining ones would
require additional refactoring that feels outside the scope of this PR.
* Remove getLazyComponentTypeIfResolved
* Return baseProps instead of null
The caller compares the result to baseProps to see if anything changed.
* Avoid redundant checks by inlining getFiberTagFromObjectType
* Move tag resolution to ReactFiber module
* Pass next props to update* functions
We should do this with all types of work in the future.
* Refine component type before pushing/popping context
Removes unnecessary checks.
* Replace all occurrences of _reactResult with helper
* Move shared thenable logic to `shared` package
* Check type of wrapper object before resolving to `default` export
* Return resolved tag instead of reassigning
