While debugging #30536 I happened to notice that the bug only reproduced
when there was interleaving scopes, and observed that an unpruned scope
nested inside of a pruned one was not being visited by
CollectPromotableTemporaries, which keeps track of which identifiers
should be promoted later. Therefore when actually promoting temporaries
we were skipping over the identifiers in children of pruned scopes
ghstack-source-id: d805f62f22
Pull Request resolved: https://github.com/facebook/react/pull/30537
The invalid GraphQL in these fixtures somehow causes an unhandled
promise rejection error when running `yarn prettier-all`. This fixes
that issue by making the GraphQL valid.
To handle more cases, always append the synthetic outlined function as a
new child of the module rather than make assumptions about the original
function. This should handle whatever case where the original function
expression may be a child of a variety of parents
ghstack-source-id: 8581edb8be
Pull Request resolved: https://github.com/facebook/react/pull/30466
Addresses follow up feedback from #30446. Since the outlined function is
guaranteed to have a module-scoped unique identifier name, we can
simplify the insertion logic for the outlined function to always emit a
function declaration rather than switch based on the original function
type. This is fine because the outlined function is synthetic anyway.
ghstack-source-id: 0a4d1f7b0a
Pull Request resolved: https://github.com/facebook/react/pull/30464
If a function expression that mutates a global is passed as a prop,
we don't throw an error as we assume it's not called in render.
But if this function expression is captured in an object and passed down
as prop, we throw an error.
ghstack-source-id: 74cacee09f
Pull Request resolved: https://github.com/facebook/react/pull/30456
Previously we would insert new (Arrow)FunctionExpressions as a sibling
of the original function. However this would break in the outlining case
as it would cause the original function expression's parent to become a
SequenceExpression, breaking a bunch of assumptions in the babel plugin.
To get around this, we synthesize a new VariableDeclaration to contain
the newly inserted function expression and therefore insert it as a true
sibling to the original function.
Yeah, it's kinda gross
ghstack-source-id: df13e3b439
Pull Request resolved: https://github.com/facebook/react/pull/30446
I discovered this compiler crash while trying to do an internal sync of
the compiler. Any kind of outlining appears to crash the babel plugin
when the component is a function expression.
ghstack-source-id: 4f717674af
Pull Request resolved: https://github.com/facebook/react/pull/30443
Addresses discussion at https://github.com/facebook/react/pull/30399#discussion_r1684693021. Once we've constructed scopes it's invalid to use identifier mutable ranges. The only places we can do this which i can find are ValidateMemoizedEffectDeps (which is already flawed and disabled by default) and ValidatePreservedManualMemoization. I added a todo to the former, and fixed up the latter.
The idea of the fix is that for StartMemo dependencies, if they needed to be memoized (identifier.scope != null) then that scope should exist and should have already completed. If they didn't need a scope or can't have one created (eg their range spans a hook), then their scope would be pruned. So if the scope is set, not pruned, and not completed, then it's an error.
For declarations (FinishMemo) the existing logic applies unchanged.
ghstack-source-id: af5bfd8855
Pull Request resolved: https://github.com/facebook/react/pull/30428
Later passes may rely on HIR invariants such as blocks being in RPO or instructions having unique, ascending InstructionIds. However, BuildReactiveScopeTerminalsHIR doesn't currently gurantee this.
This PR updates that pass to first restore RPO, fixup predecessors (the previous logic tried to do this but failed on unreachable blocks, where `markPredecessors()` handles that case), and renumber instructions. Then it walks instructions and scopes to update identifier and scope ranges given the new instruction ids.
ghstack-source-id: 2a99df02ac
Pull Request resolved: https://github.com/facebook/react/pull/30399
Once we create scopes, we should prefer to use the block structure to identify active scope ranges rather than the scope range. They _should_ always be in sync, but ultimately the block structure determine the active range (ie the id of the 'scope' terminal and the terminal's fallthrough block).
ghstack-source-id: 730b6d1cfa
Pull Request resolved: https://github.com/facebook/react/pull/30398
babel-plugin-idx enforces that its 2nd argument is an arrow function, so
outlining needs to skip over lambdas that are args to idx. This PR adds
a small repro highlighting the issue.
ghstack-source-id: b4627ec552
Pull Request resolved: https://github.com/facebook/react/pull/30435
To surface any potential conflicts with this plugin, let's install it
into snap so we can surface any runtime errors after compilation
ghstack-source-id: 545eee6fb7
Pull Request resolved: https://github.com/facebook/react/pull/30434
This will allow us to parse new flow syntax since the `flow` parser is
no longer updated.
I had to exclude some files and have them fall back to `flow` parser
since they contain invalid graphql syntax that makes the plugin crash.
Updates the prettier config to format all `.ts` and `.tsx` files in the
repo using the existing defaults and removing overrides.
The first commit in this PR contains the config changes, the second is
just the result of running `yarn prettier-all`.
Addresses a follow-up from the previous PR. Destructured function params are currently not eagerly promoted to temporaries: we wait until PromotedUsedTemporaries. But params _always_ have to be named, so we can promote when constructing HIR.
ghstack-source-id: a6f665762e
Pull Request resolved: https://github.com/facebook/react/pull/30332
Implements general-purpose function outlining. Specifically, anonymous function expressions which have no dependencies/context variables are extracted into named top-level functions. The original function expression is replaced with a `LoadGlobal` of the generated name.
Note that the architecture is designed to allow very general purpose forms of outlining, though we currently are very conservative in what we outline. Specifically, the outlining allows annotating functions with an optional ReactiveFunctionType, which if set will cause the outlined function to get compiled as that type. So we could for example outline a helper hook or helper component, set the type, and then have the hook/component get memoized as well. For now though we just outline with no type set, and generate the function as-is without running it through compilation.
ghstack-source-id: 2a7da6c8e8
Pull Request resolved: https://github.com/facebook/react/pull/30331
Refactors Program.ts to first traverse the `Program` node and build up a queue of functions to visit, then iterate that queue and compile the functions. This doesn't change behavior, but allows the next diff to add additional items to the queue during compilation (for function outlining).
ghstack-source-id: 858527c30c
Pull Request resolved: https://github.com/facebook/react/pull/30330
Stores the Babel `Scope` object for the current function on the Environment, allowing access later for generating new globally unique names. The idea is to expose a small subset of the capabilities of the Scope API via Environment, so that the rest of the compiler remains decoupled from Babel. Ideally we'd use our own Scope implementation too, but we can punt on that for now since the parts we're using (global id generation) seem pretty reliable.
ghstack-source-id: 37f7113b11
Pull Request resolved: https://github.com/facebook/react/pull/30328
I'm experimenting with a new pass that sometimes creates scopes with early returns earlier in the pipeline, but there are a few passes that assume that can't happen. This PR is updating those passes just to be more resilient to help unblock experimentation.
ghstack-source-id: a9e348181d
Pull Request resolved: https://github.com/facebook/react/pull/30333
We have an experimental mode where we generate scopes for simple phi values, even if they aren't subsequently mutated. This mode was incorrectly generating scope ranges, leaving the start at 0 which is invalid. The fix is to allow non-zero identifier ranges to overwrite the scope start (rather than taking the min) if the scope start is still zero.
ghstack-source-id: ecbb04c96e
Pull Request resolved: https://github.com/facebook/react/pull/30321