Compare commits

...

4 Commits

Author SHA1 Message Date
Jorge Cabiedes Acosta
0fae264d51 [compiler] _exp version of ValidateNoDerivedComputationsInEffects take precedence over stable version when enabled
Summary:
We should only run one version of the validation. I think it makes sense that if the exp version is enable it takes precedence over the stable one
2025-11-11 09:19:40 -08:00
Jorge Cabiedes Acosta
2ac39db287 [compiler] Update test snap to include fixture comment
Summary:
I missed this test case failing and now having @loggerTestOnly after landing some other PRs good to know they're not land blocking
2025-11-11 09:19:40 -08:00
Jorge Cabiedes
100fc4a8cf [compiler] Prevent local state source variables from depending on other state (#35044)
Summary:
When a local state is created sometimes it uses a `prop` or even other
local state for its initial value.

This value is only relevant on first render so we shouldn't consider it
part of our data flow

Test Plan:
Added tests
2025-11-10 12:29:34 -08:00
Jorge Cabiedes
92ac4e8b80 [compiler] Don't validate when effect cleanup function depends on effect localized setState state derived values (#35020)
Summary:
If we are using a clean up function in an effect and that clean up
function depends on a value that is used to set the state we are
validating for we shouldn't throw an error since it is a valid use case
for an effect.

Test Plan:
added test

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/35020).
* #35044
* __->__ #35020
2025-11-10 12:28:19 -08:00
6 changed files with 238 additions and 6 deletions

View File

@@ -272,12 +272,10 @@ function runWithEnvironment(
validateNoSetStateInRender(hir).unwrap();
}
if (env.config.validateNoDerivedComputationsInEffects) {
validateNoDerivedComputationsInEffects(hir);
}
if (env.config.validateNoDerivedComputationsInEffects_exp) {
env.logErrors(validateNoDerivedComputationsInEffects_exp(hir));
} else if (env.config.validateNoDerivedComputationsInEffects) {
validateNoDerivedComputationsInEffects(hir);
}
if (env.config.validateNoSetStateInEffects) {

View File

@@ -358,8 +358,14 @@ function recordInstructionDerivations(
context.effects.add(effectFunction.loweredFunc.func);
}
} else if (isUseStateType(lvalue.identifier) && value.args.length > 0) {
isSource = true;
typeOfValue = joinValue(typeOfValue, 'fromState');
typeOfValue = 'fromState';
context.derivationCache.addDerivationEntry(
lvalue,
new Set(),
typeOfValue,
true,
);
return;
}
}
@@ -568,6 +574,26 @@ function renderTree(
return result;
}
function getFnLocalDeps(
fn: FunctionExpression | undefined,
): Set<IdentifierId> | undefined {
if (!fn) {
return undefined;
}
const deps: Set<IdentifierId> = new Set();
for (const [, block] of fn.loweredFunc.func.body.blocks) {
for (const instr of block.instructions) {
if (instr.value.kind === 'LoadLocal') {
deps.add(instr.value.place.identifier.id);
}
}
}
return deps;
}
function validateEffect(
effectFunction: HIRFunction,
context: ValidationContext,
@@ -586,8 +612,23 @@ function validateEffect(
Set<SourceLocation>
> = new Map();
let cleanUpFunctionDeps: Set<IdentifierId> | undefined;
const globals: Set<IdentifierId> = new Set();
for (const block of effectFunction.body.blocks.values()) {
/*
* if the block is in an effect and is of type return then its an effect's cleanup function
* if the cleanup function depends on a value from which effect-set state is derived then
* we can't validate
*/
if (
block.terminal.kind === 'return' &&
block.terminal.returnVariant === 'Explicit'
) {
cleanUpFunctionDeps = getFnLocalDeps(
context.functions.get(block.terminal.value.identifier.id),
);
}
for (const pred of block.preds) {
if (!seenBlocks.has(pred)) {
// skip if block has a back edge
@@ -698,6 +739,12 @@ function validateEffect(
),
);
for (const dep of derivedSetStateCall.sourceIds) {
if (cleanUpFunctionDeps !== undefined && cleanUpFunctionDeps.has(dep)) {
return;
}
}
const propsArr = Array.from(propsSet);
const stateArr = Array.from(stateSet);

View File

@@ -0,0 +1,76 @@
## Input
```javascript
// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
import {useEffect, useState} from 'react';
function Component(file: File) {
const [imageUrl, setImageUrl] = useState(null);
/*
* Cleaning up the variable or a source of the variable used to setState
* inside the effect communicates that we always need to clean up something
* which is a valid use case for useEffect. In which case we want to
* avoid an throwing
*/
useEffect(() => {
const imageUrlPrepared = URL.createObjectURL(file);
setImageUrl(imageUrlPrepared);
return () => URL.revokeObjectURL(imageUrlPrepared);
}, [file]);
return <Image src={imageUrl} xstyle={styles.imageSizeLimits} />;
}
```
## Code
```javascript
import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
import { useEffect, useState } from "react";
function Component(file) {
const $ = _c(5);
const [imageUrl, setImageUrl] = useState(null);
let t0;
let t1;
if ($[0] !== file) {
t0 = () => {
const imageUrlPrepared = URL.createObjectURL(file);
setImageUrl(imageUrlPrepared);
return () => URL.revokeObjectURL(imageUrlPrepared);
};
t1 = [file];
$[0] = file;
$[1] = t0;
$[2] = t1;
} else {
t0 = $[1];
t1 = $[2];
}
useEffect(t0, t1);
let t2;
if ($[3] !== imageUrl) {
t2 = <Image src={imageUrl} xstyle={styles.imageSizeLimits} />;
$[3] = imageUrl;
$[4] = t2;
} else {
t2 = $[4];
}
return t2;
}
```
## Logs
```
{"kind":"CompileSuccess","fnLoc":{"start":{"line":5,"column":0,"index":108},"end":{"line":21,"column":1,"index":700},"filename":"effect-with-cleanup-function-depending-on-derived-computation-value.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
```
### Eval output
(kind: exception) Fixture not implemented

View File

@@ -0,0 +1,21 @@
// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
import {useEffect, useState} from 'react';
function Component(file: File) {
const [imageUrl, setImageUrl] = useState(null);
/*
* Cleaning up the variable or a source of the variable used to setState
* inside the effect communicates that we always need to clean up something
* which is a valid use case for useEffect. In which case we want to
* avoid an throwing
*/
useEffect(() => {
const imageUrlPrepared = URL.createObjectURL(file);
setImageUrl(imageUrlPrepared);
return () => URL.revokeObjectURL(imageUrlPrepared);
}, [file]);
return <Image src={imageUrl} xstyle={styles.imageSizeLimits} />;
}

View File

@@ -0,0 +1,72 @@
## Input
```javascript
// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
function Component({prop}) {
const [s, setS] = useState();
const [second, setSecond] = useState(prop);
/*
* `second` is a source of state. It will inherit the value of `prop` in
* the first render, but after that it will no longer be updated when
* `prop` changes. So we shouldn't consider `second` as being derived from
* `prop`
*/
useEffect(() => {
setS(second);
}, [second]);
return <div>{s}</div>;
}
```
## Code
```javascript
import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
function Component(t0) {
const $ = _c(5);
const { prop } = t0;
const [s, setS] = useState();
const [second] = useState(prop);
let t1;
let t2;
if ($[0] !== second) {
t1 = () => {
setS(second);
};
t2 = [second];
$[0] = second;
$[1] = t1;
$[2] = t2;
} else {
t1 = $[1];
t2 = $[2];
}
useEffect(t1, t2);
let t3;
if ($[3] !== s) {
t3 = <div>{s}</div>;
$[3] = s;
$[4] = t3;
} else {
t3 = $[4];
}
return t3;
}
```
## Logs
```
{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [second]\n\nData Flow Tree:\n└── second (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":14,"column":4,"index":443},"end":{"line":14,"column":8,"index":447},"filename":"usestate-derived-from-prop-no-show-in-data-flow-tree.ts","identifierName":"setS"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":64},"end":{"line":18,"column":1,"index":500},"filename":"usestate-derived-from-prop-no-show-in-data-flow-tree.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
```
### Eval output
(kind: exception) Fixture not implemented

View File

@@ -0,0 +1,18 @@
// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
function Component({prop}) {
const [s, setS] = useState();
const [second, setSecond] = useState(prop);
/*
* `second` is a source of state. It will inherit the value of `prop` in
* the first render, but after that it will no longer be updated when
* `prop` changes. So we shouldn't consider `second` as being derived from
* `prop`
*/
useEffect(() => {
setS(second);
}, [second]);
return <div>{s}</div>;
}