Infer if a function is a component or hook when we're deciding to compile a
function and store that in the environment.
This is used in passes like InferReferenceEffects rather than having to re-parse
the name in each pass.
filepath
Internal rollout currently has a good number of test failures.
`enableEmitInstrumentForget` can help developers understand which functions /
files they should look at:
```
// input
function Foo() {
userCode();
// ...
}
// output
function Foo() {
if (__DEV__ && inE2eTestMode) {
logRender("Foo", "/path/to/filename.js");
}
const $ = useMemoCache(...);
userCode();
}
```
This PR changes the way we compile ArrowFunctionExpression to allow compiling
more cases, such as within `React.forwardRef()`. We no longer convert arrow
functions to function declarations. Instead, CodeGenerator emits a generic
`CodegenFunction` type, and `Program.ts` is responsible for converting that to
the appropriate type. The rule is basically:
* Retain the original node type by default. Function declaration in, function
declaration out. Arrow function in, arrow function out.
* When gating is enabled, we emit a ConditionalExpression instead of creating a
temporary variable. If the original (and hence compiled) functions are function
declarations, we force them into FunctionExpressions only here, since we need an
expression for each branch of the conditional. Then the rules are:
* If this is a `export function Foo` ie a named export, replace it with a
variable declaration with the conditional expression as the initializer, and the
function name as the variable name.
* Else, just replace the original function node with the conditional. This works
for all other cases.
I'm open to feedback but this seems like a pretty robust approach and will allow
us to support a lot of real-world cases that we didn't yet, so i think we need
_something_ in this direction.
Sorry about the thrash in advance! This removes the top level `forget` directory
which adds unnecessary nesting to our repo
Hopefully everything still works
Sathya Gunasekaran
Mofei Zhang
Joe Savona
lauren