react/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
mofeiZ 8039f1b2a0
[compiler] Fix inferEffectDependencies lint false positives (#32769)
Currently, inferred effect dependencies are considered a
"compiler-required" feature. This means that untransformed callsites
should escalate to a build error.

`ValidateNoUntransformedReferences` iterates 'special effect' callsites
and checks that the compiler was able to successfully transform them.
Prior to this PR, this relied on checking the number of arguments passed
to this special effect.

This obviously doesn't work with `noEmit: true`, which is used for our
eslint plugin (this avoids mutating the babel program as other linters
run with the same ast). This PR adds a set of `babel.SourceLocation`s to
do best effort matching in this mode.
2025-03-27 12:18:50 -04:00

1148 lines
33 KiB
TypeScript

/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
import {NodePath} from '@babel/core';
import * as t from '@babel/types';
import {
CompilerError,
CompilerErrorDetail,
ErrorSeverity,
} from '../CompilerError';
import {EnvironmentConfig, ReactFunctionType} from '../HIR/Environment';
import {CodegenFunction} from '../ReactiveScopes';
import {isComponentDeclaration} from '../Utils/ComponentDeclaration';
import {isHookDeclaration} from '../Utils/HookDeclaration';
import {assertExhaustive} from '../Utils/utils';
import {insertGatedFunctionDeclaration} from './Gating';
import {
addImportsToProgram,
ProgramContext,
validateRestrictedImports,
} from './Imports';
import {CompilerReactTarget, PluginOptions} from './Options';
import {compileFn} from './Pipeline';
import {
filterSuppressionsThatAffectFunction,
findProgramSuppressions,
suppressionsToCompilerError,
} from './Suppression';
import {GeneratedSource} from '../HIR';
export type CompilerPass = {
opts: PluginOptions;
filename: string | null;
comments: Array<t.CommentBlock | t.CommentLine>;
code: string | null;
};
export const OPT_IN_DIRECTIVES = new Set(['use forget', 'use memo']);
export const OPT_OUT_DIRECTIVES = new Set(['use no forget', 'use no memo']);
export function findDirectiveEnablingMemoization(
directives: Array<t.Directive>,
): Array<t.Directive> {
return directives.filter(directive =>
OPT_IN_DIRECTIVES.has(directive.value.value),
);
}
export function findDirectiveDisablingMemoization(
directives: Array<t.Directive>,
): Array<t.Directive> {
return directives.filter(directive =>
OPT_OUT_DIRECTIVES.has(directive.value.value),
);
}
function isCriticalError(err: unknown): boolean {
return !(err instanceof CompilerError) || err.isCritical();
}
function isConfigError(err: unknown): boolean {
if (err instanceof CompilerError) {
return err.details.some(
detail => detail.severity === ErrorSeverity.InvalidConfig,
);
}
return false;
}
export type BabelFn =
| NodePath<t.FunctionDeclaration>
| NodePath<t.FunctionExpression>
| NodePath<t.ArrowFunctionExpression>;
export type CompileResult = {
/**
* Distinguishes existing functions that were compiled ('original') from
* functions which were outlined. Only original functions need to be gated
* if gating mode is enabled.
*/
kind: 'original' | 'outlined';
originalFn: BabelFn;
compiledFn: CodegenFunction;
};
function logError(
err: unknown,
pass: CompilerPass,
fnLoc: t.SourceLocation | null,
): void {
if (pass.opts.logger) {
if (err instanceof CompilerError) {
for (const detail of err.details) {
pass.opts.logger.logEvent(pass.filename, {
kind: 'CompileError',
fnLoc,
detail: detail.options,
});
}
} else {
let stringifiedError;
if (err instanceof Error) {
stringifiedError = err.stack ?? err.message;
} else {
stringifiedError = err?.toString() ?? '[ null ]';
}
pass.opts.logger.logEvent(pass.filename, {
kind: 'PipelineError',
fnLoc,
data: stringifiedError,
});
}
}
}
function handleError(
err: unknown,
pass: CompilerPass,
fnLoc: t.SourceLocation | null,
): void {
logError(err, pass, fnLoc);
if (
pass.opts.panicThreshold === 'all_errors' ||
(pass.opts.panicThreshold === 'critical_errors' && isCriticalError(err)) ||
isConfigError(err) // Always throws regardless of panic threshold
) {
throw err;
}
}
export function createNewFunctionNode(
originalFn: BabelFn,
compiledFn: CodegenFunction,
): t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression {
let transformedFn:
| t.FunctionDeclaration
| t.ArrowFunctionExpression
| t.FunctionExpression;
switch (originalFn.node.type) {
case 'FunctionDeclaration': {
const fn: t.FunctionDeclaration = {
type: 'FunctionDeclaration',
id: compiledFn.id,
loc: originalFn.node.loc ?? null,
async: compiledFn.async,
generator: compiledFn.generator,
params: compiledFn.params,
body: compiledFn.body,
};
transformedFn = fn;
break;
}
case 'ArrowFunctionExpression': {
const fn: t.ArrowFunctionExpression = {
type: 'ArrowFunctionExpression',
loc: originalFn.node.loc ?? null,
async: compiledFn.async,
generator: compiledFn.generator,
params: compiledFn.params,
expression: originalFn.node.expression,
body: compiledFn.body,
};
transformedFn = fn;
break;
}
case 'FunctionExpression': {
const fn: t.FunctionExpression = {
type: 'FunctionExpression',
id: compiledFn.id,
loc: originalFn.node.loc ?? null,
async: compiledFn.async,
generator: compiledFn.generator,
params: compiledFn.params,
body: compiledFn.body,
};
transformedFn = fn;
break;
}
default: {
assertExhaustive(
originalFn.node,
`Creating unhandled function: ${originalFn.node}`,
);
}
}
// Avoid visiting the new transformed version
ALREADY_COMPILED.add(transformedFn);
return transformedFn;
}
function insertNewOutlinedFunctionNode(
program: NodePath<t.Program>,
originalFn: BabelFn,
compiledFn: CodegenFunction,
): BabelFn {
switch (originalFn.type) {
case 'FunctionDeclaration': {
return originalFn.insertAfter(
createNewFunctionNode(originalFn, compiledFn),
)[0]!;
}
/**
* We can't just append the outlined function as a sibling of the original function if it is an
* (Arrow)FunctionExpression parented by a VariableDeclaration, as this would cause its parent
* to become a SequenceExpression instead which breaks a bunch of assumptions elsewhere in the
* plugin.
*
* To get around this, we always synthesize a new FunctionDeclaration for the outlined function
* and insert it as a true sibling to the original function.
*/
case 'ArrowFunctionExpression':
case 'FunctionExpression': {
const fn: t.FunctionDeclaration = {
type: 'FunctionDeclaration',
id: compiledFn.id,
loc: originalFn.node.loc ?? null,
async: compiledFn.async,
generator: compiledFn.generator,
params: compiledFn.params,
body: compiledFn.body,
};
const insertedFuncDecl = program.pushContainer('body', [fn])[0]!;
CompilerError.invariant(insertedFuncDecl.isFunctionDeclaration(), {
reason: 'Expected inserted function declaration',
description: `Got: ${insertedFuncDecl}`,
loc: insertedFuncDecl.node?.loc ?? null,
});
return insertedFuncDecl;
}
default: {
assertExhaustive(
originalFn,
`Inserting unhandled function: ${originalFn}`,
);
}
}
}
/*
* This is a hack to work around what seems to be a Babel bug. Babel doesn't
* consistently respect the `skip()` function to avoid revisiting a node within
* a pass, so we use this set to track nodes that we have compiled.
*/
const ALREADY_COMPILED: WeakSet<object> | Set<object> = new (WeakSet ?? Set)();
const DEFAULT_ESLINT_SUPPRESSIONS = [
'react-hooks/exhaustive-deps',
'react-hooks/rules-of-hooks',
];
function isFilePartOfSources(
sources: Array<string> | ((filename: string) => boolean),
filename: string,
): boolean {
if (typeof sources === 'function') {
return sources(filename);
}
for (const prefix of sources) {
if (filename.indexOf(prefix) !== -1) {
return true;
}
}
return false;
}
export type CompileProgramResult = {
retryErrors: Array<{fn: BabelFn; error: CompilerError}>;
inferredEffectLocations: Set<t.SourceLocation>;
};
/**
* `compileProgram` is directly invoked by the react-compiler babel plugin, so
* exceptions thrown by this function will fail the babel build.
* - call `handleError` if your error is recoverable.
* Unless the error is a warning / info diagnostic, compilation of a function
* / entire file should also be skipped.
* - throw an exception if the error is fatal / not recoverable.
* Examples of this are invalid compiler configs or failure to codegen outlined
* functions *after* already emitting optimized components / hooks that invoke
* the outlined functions.
*/
export function compileProgram(
program: NodePath<t.Program>,
pass: CompilerPass,
): CompileProgramResult | null {
if (shouldSkipCompilation(program, pass)) {
return null;
}
const environment = pass.opts.environment;
const restrictedImportsErr = validateRestrictedImports(program, environment);
if (restrictedImportsErr) {
handleError(restrictedImportsErr, pass, null);
return null;
}
const programContext = new ProgramContext(
program,
pass.opts.target,
environment.hookPattern,
);
/*
* Record lint errors and critical errors as depending on Forget's config,
* we may still need to run Forget's analysis on every function (even if we
* have already encountered errors) for reporting.
*/
const suppressions = findProgramSuppressions(
pass.comments,
pass.opts.eslintSuppressionRules ?? DEFAULT_ESLINT_SUPPRESSIONS,
pass.opts.flowSuppressions,
);
const queue: Array<{
kind: 'original' | 'outlined';
fn: BabelFn;
fnType: ReactFunctionType;
}> = [];
const compiledFns: Array<CompileResult> = [];
const traverseFunction = (fn: BabelFn, pass: CompilerPass): void => {
const fnType = getReactFunctionType(fn, pass, environment);
if (fnType === null || ALREADY_COMPILED.has(fn.node)) {
return;
}
/*
* We may be generating a new FunctionDeclaration node, so we must skip over it or this
* traversal will loop infinitely.
* Ensure we avoid visiting the original function again.
*/
ALREADY_COMPILED.add(fn.node);
fn.skip();
queue.push({kind: 'original', fn, fnType});
};
// Main traversal to compile with Forget
program.traverse(
{
ClassDeclaration(node: NodePath<t.ClassDeclaration>) {
/*
* Don't visit functions defined inside classes, because they
* can reference `this` which is unsafe for compilation
*/
node.skip();
return;
},
ClassExpression(node: NodePath<t.ClassExpression>) {
/*
* Don't visit functions defined inside classes, because they
* can reference `this` which is unsafe for compilation
*/
node.skip();
return;
},
FunctionDeclaration: traverseFunction,
FunctionExpression: traverseFunction,
ArrowFunctionExpression: traverseFunction,
},
{
...pass,
opts: {...pass.opts, ...pass.opts},
filename: pass.filename ?? null,
},
);
const retryErrors: Array<{fn: BabelFn; error: CompilerError}> = [];
const inferredEffectLocations = new Set<t.SourceLocation>();
const processFn = (
fn: BabelFn,
fnType: ReactFunctionType,
): null | CodegenFunction => {
let optInDirectives: Array<t.Directive> = [];
let optOutDirectives: Array<t.Directive> = [];
if (fn.node.body.type === 'BlockStatement') {
optInDirectives = findDirectiveEnablingMemoization(
fn.node.body.directives,
);
optOutDirectives = findDirectiveDisablingMemoization(
fn.node.body.directives,
);
}
/**
* Note that Babel does not attach comment nodes to nodes; they are dangling off of the
* Program node itself. We need to figure out whether an eslint suppression range
* applies to this function first.
*/
const suppressionsInFunction = filterSuppressionsThatAffectFunction(
suppressions,
fn,
);
let compileResult:
| {kind: 'compile'; compiledFn: CodegenFunction}
| {kind: 'error'; error: unknown};
if (suppressionsInFunction.length > 0) {
compileResult = {
kind: 'error',
error: suppressionsToCompilerError(suppressionsInFunction),
};
} else {
try {
compileResult = {
kind: 'compile',
compiledFn: compileFn(
fn,
environment,
fnType,
'all_features',
programContext,
pass.opts.logger,
pass.filename,
pass.code,
),
};
} catch (err) {
compileResult = {kind: 'error', error: err};
}
}
if (compileResult.kind === 'error') {
/**
* If an opt out directive is present, log only instead of throwing and don't mark as
* containing a critical error.
*/
if (optOutDirectives.length > 0) {
logError(compileResult.error, pass, fn.node.loc ?? null);
} else {
handleError(compileResult.error, pass, fn.node.loc ?? null);
}
// If non-memoization features are enabled, retry regardless of error kind
if (
!(environment.enableFire || environment.inferEffectDependencies != null)
) {
return null;
}
try {
compileResult = {
kind: 'compile',
compiledFn: compileFn(
fn,
environment,
fnType,
'no_inferred_memo',
programContext,
pass.opts.logger,
pass.filename,
pass.code,
),
};
if (
!compileResult.compiledFn.hasFireRewrite &&
!compileResult.compiledFn.hasInferredEffect
) {
return null;
}
} catch (err) {
// TODO: we might want to log error here, but this will also result in duplicate logging
if (err instanceof CompilerError) {
retryErrors.push({fn, error: err});
}
return null;
}
}
pass.opts.logger?.logEvent(pass.filename, {
kind: 'CompileSuccess',
fnLoc: fn.node.loc ?? null,
fnName: compileResult.compiledFn.id?.name ?? null,
memoSlots: compileResult.compiledFn.memoSlotsUsed,
memoBlocks: compileResult.compiledFn.memoBlocks,
memoValues: compileResult.compiledFn.memoValues,
prunedMemoBlocks: compileResult.compiledFn.prunedMemoBlocks,
prunedMemoValues: compileResult.compiledFn.prunedMemoValues,
});
/**
* Always compile functions with opt in directives.
*/
if (optInDirectives.length > 0) {
return compileResult.compiledFn;
} else if (pass.opts.compilationMode === 'annotation') {
/**
* No opt-in directive in annotation mode, so don't insert the compiled function.
*/
return null;
}
/**
* Otherwise if 'use no forget/memo' is present, we still run the code through the compiler
* for validation but we don't mutate the babel AST. This allows us to flag if there is an
* unused 'use no forget/memo' directive.
*/
if (pass.opts.ignoreUseNoForget === false && optOutDirectives.length > 0) {
for (const directive of optOutDirectives) {
pass.opts.logger?.logEvent(pass.filename, {
kind: 'CompileSkip',
fnLoc: fn.node.body.loc ?? null,
reason: `Skipped due to '${directive.value.value}' directive.`,
loc: directive.loc ?? null,
});
}
return null;
}
if (!pass.opts.noEmit) {
return compileResult.compiledFn;
}
/**
* inferEffectDependencies + noEmit is currently only used for linting. In
* this mode, add source locations for where the compiler *can* infer effect
* dependencies.
*/
for (const loc of compileResult.compiledFn.inferredEffectLocations) {
if (loc !== GeneratedSource) inferredEffectLocations.add(loc);
}
return null;
};
while (queue.length !== 0) {
const current = queue.shift()!;
const compiled = processFn(current.fn, current.fnType);
if (compiled === null) {
continue;
}
for (const outlined of compiled.outlined) {
CompilerError.invariant(outlined.fn.outlined.length === 0, {
reason: 'Unexpected nested outlined functions',
loc: outlined.fn.loc,
});
const fn = insertNewOutlinedFunctionNode(
program,
current.fn,
outlined.fn,
);
fn.skip();
ALREADY_COMPILED.add(fn.node);
if (outlined.type !== null) {
queue.push({
kind: 'outlined',
fn,
fnType: outlined.type,
});
}
}
compiledFns.push({
kind: current.kind,
compiledFn: compiled,
originalFn: current.fn,
});
}
/**
* Do not modify source if there is a module scope level opt out directive.
*/
const moduleScopeOptOutDirectives = findDirectiveDisablingMemoization(
program.node.directives,
);
if (moduleScopeOptOutDirectives.length > 0) {
return null;
}
/*
* Only insert Forget-ified functions if we have not encountered a critical
* error elsewhere in the file, regardless of bailout mode.
*/
const referencedBeforeDeclared =
pass.opts.gating != null
? getFunctionReferencedBeforeDeclarationAtTopLevel(program, compiledFns)
: null;
for (const result of compiledFns) {
const {kind, originalFn, compiledFn} = result;
const transformedFn = createNewFunctionNode(originalFn, compiledFn);
if (referencedBeforeDeclared != null && kind === 'original') {
CompilerError.invariant(pass.opts.gating != null, {
reason: "Expected 'gating' import to be present",
loc: null,
});
insertGatedFunctionDeclaration(
originalFn,
transformedFn,
programContext,
pass.opts.gating,
referencedBeforeDeclared.has(result),
);
} else {
originalFn.replaceWith(transformedFn);
}
}
// Forget compiled the component, we need to update existing imports of useMemoCache
if (compiledFns.length > 0) {
addImportsToProgram(program, programContext);
}
return {retryErrors, inferredEffectLocations};
}
function shouldSkipCompilation(
program: NodePath<t.Program>,
pass: CompilerPass,
): boolean {
if (pass.opts.sources) {
if (pass.filename === null) {
const error = new CompilerError();
error.pushErrorDetail(
new CompilerErrorDetail({
reason: `Expected a filename but found none.`,
description:
"When the 'sources' config options is specified, the React compiler will only compile files with a name",
severity: ErrorSeverity.InvalidConfig,
loc: null,
}),
);
handleError(error, pass, null);
return true;
}
if (!isFilePartOfSources(pass.opts.sources, pass.filename)) {
return true;
}
}
if (
hasMemoCacheFunctionImport(
program,
getReactCompilerRuntimeModule(pass.opts.target),
)
) {
return true;
}
return false;
}
function getReactFunctionType(
fn: BabelFn,
pass: CompilerPass,
/**
* TODO(mofeiZ): remove once we validate PluginOptions with Zod
*/
environment: EnvironmentConfig,
): ReactFunctionType | null {
const hookPattern = environment.hookPattern;
if (fn.node.body.type === 'BlockStatement') {
if (findDirectiveEnablingMemoization(fn.node.body.directives).length > 0)
return getComponentOrHookLike(fn, hookPattern) ?? 'Other';
}
// Component and hook declarations are known components/hooks
let componentSyntaxType: ReactFunctionType | null = null;
if (fn.isFunctionDeclaration()) {
if (isComponentDeclaration(fn.node)) {
componentSyntaxType = 'Component';
} else if (isHookDeclaration(fn.node)) {
componentSyntaxType = 'Hook';
}
}
switch (pass.opts.compilationMode) {
case 'annotation': {
// opt-ins are checked above
return null;
}
case 'infer': {
// Check if this is a component or hook-like function
return componentSyntaxType ?? getComponentOrHookLike(fn, hookPattern);
}
case 'syntax': {
return componentSyntaxType;
}
case 'all': {
// Compile only top level functions
if (fn.scope.getProgramParent() !== fn.scope.parent) {
return null;
}
return getComponentOrHookLike(fn, hookPattern) ?? 'Other';
}
default: {
assertExhaustive(
pass.opts.compilationMode,
`Unexpected compilationMode \`${pass.opts.compilationMode}\``,
);
}
}
}
/**
* Returns true if the program contains an `import {c} from "<moduleName>"` declaration,
* regardless of the local name of the 'c' specifier and the presence of other specifiers
* in the same declaration.
*/
function hasMemoCacheFunctionImport(
program: NodePath<t.Program>,
moduleName: string,
): boolean {
let hasUseMemoCache = false;
program.traverse({
ImportSpecifier(path) {
const imported = path.get('imported');
let importedName: string | null = null;
if (imported.isIdentifier()) {
importedName = imported.node.name;
} else if (imported.isStringLiteral()) {
importedName = imported.node.value;
}
if (
importedName === 'c' &&
path.parentPath.isImportDeclaration() &&
path.parentPath.get('source').node.value === moduleName
) {
hasUseMemoCache = true;
}
},
});
return hasUseMemoCache;
}
function isHookName(s: string, hookPattern: string | null): boolean {
if (hookPattern !== null) {
return new RegExp(hookPattern).test(s);
}
return /^use[A-Z0-9]/.test(s);
}
/*
* We consider hooks to be a hook name identifier or a member expression
* containing a hook name.
*/
function isHook(
path: NodePath<t.Expression | t.PrivateName>,
hookPattern: string | null,
): boolean {
if (path.isIdentifier()) {
return isHookName(path.node.name, hookPattern);
} else if (
path.isMemberExpression() &&
!path.node.computed &&
isHook(path.get('property'), hookPattern)
) {
const obj = path.get('object').node;
const isPascalCaseNameSpace = /^[A-Z].*/;
return obj.type === 'Identifier' && isPascalCaseNameSpace.test(obj.name);
} else {
return false;
}
}
/*
* Checks if the node is a React component name. React component names must
* always start with an uppercase letter.
*/
function isComponentName(path: NodePath<t.Expression>): boolean {
return path.isIdentifier() && /^[A-Z]/.test(path.node.name);
}
function isReactAPI(
path: NodePath<t.Expression | t.PrivateName | t.V8IntrinsicIdentifier>,
functionName: string,
): boolean {
const node = path.node;
return (
(node.type === 'Identifier' && node.name === functionName) ||
(node.type === 'MemberExpression' &&
node.object.type === 'Identifier' &&
node.object.name === 'React' &&
node.property.type === 'Identifier' &&
node.property.name === functionName)
);
}
/*
* Checks if the node is a callback argument of forwardRef. This render function
* should follow the rules of hooks.
*/
function isForwardRefCallback(path: NodePath<t.Expression>): boolean {
return !!(
path.parentPath.isCallExpression() &&
path.parentPath.get('callee').isExpression() &&
isReactAPI(path.parentPath.get('callee'), 'forwardRef')
);
}
/*
* Checks if the node is a callback argument of React.memo. This anonymous
* functional component should follow the rules of hooks.
*/
function isMemoCallback(path: NodePath<t.Expression>): boolean {
return (
path.parentPath.isCallExpression() &&
path.parentPath.get('callee').isExpression() &&
isReactAPI(path.parentPath.get('callee'), 'memo')
);
}
function isValidPropsAnnotation(
annot: t.TypeAnnotation | t.TSTypeAnnotation | t.Noop | null | undefined,
): boolean {
if (annot == null) {
return true;
} else if (annot.type === 'TSTypeAnnotation') {
switch (annot.typeAnnotation.type) {
case 'TSArrayType':
case 'TSBigIntKeyword':
case 'TSBooleanKeyword':
case 'TSConstructorType':
case 'TSFunctionType':
case 'TSLiteralType':
case 'TSNeverKeyword':
case 'TSNumberKeyword':
case 'TSStringKeyword':
case 'TSSymbolKeyword':
case 'TSTupleType':
return false;
}
return true;
} else if (annot.type === 'TypeAnnotation') {
switch (annot.typeAnnotation.type) {
case 'ArrayTypeAnnotation':
case 'BooleanLiteralTypeAnnotation':
case 'BooleanTypeAnnotation':
case 'EmptyTypeAnnotation':
case 'FunctionTypeAnnotation':
case 'NumberLiteralTypeAnnotation':
case 'NumberTypeAnnotation':
case 'StringLiteralTypeAnnotation':
case 'StringTypeAnnotation':
case 'SymbolTypeAnnotation':
case 'ThisTypeAnnotation':
case 'TupleTypeAnnotation':
return false;
}
return true;
} else if (annot.type === 'Noop') {
return true;
} else {
assertExhaustive(annot, `Unexpected annotation node \`${annot}\``);
}
}
function isValidComponentParams(
params: Array<NodePath<t.Identifier | t.Pattern | t.RestElement>>,
): boolean {
if (params.length === 0) {
return true;
} else if (params.length > 0 && params.length <= 2) {
if (!isValidPropsAnnotation(params[0].node.typeAnnotation)) {
return false;
}
if (params.length === 1) {
return !params[0].isRestElement();
} else if (params[1].isIdentifier()) {
// check if second param might be a ref
const {name} = params[1].node;
return name.includes('ref') || name.includes('Ref');
} else {
/**
* Otherwise, avoid helper functions that take more than one argument.
* Helpers are _usually_ named with lowercase, but some code may
* violate this rule
*/
return false;
}
}
return false;
}
/*
* Adapted from the ESLint rule at
* https://github.com/facebook/react/blob/main/packages/eslint-plugin-react-hooks/src/RulesOfHooks.js#L90-L103
*/
function getComponentOrHookLike(
node: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
hookPattern: string | null,
): ReactFunctionType | null {
const functionName = getFunctionName(node);
// Check if the name is component or hook like:
if (functionName !== null && isComponentName(functionName)) {
let isComponent =
callsHooksOrCreatesJsx(node, hookPattern) &&
isValidComponentParams(node.get('params')) &&
!returnsNonNode(node);
return isComponent ? 'Component' : null;
} else if (functionName !== null && isHook(functionName, hookPattern)) {
// Hooks have hook invocations or JSX, but can take any # of arguments
return callsHooksOrCreatesJsx(node, hookPattern) ? 'Hook' : null;
}
/*
* Otherwise for function or arrow function expressions, check if they
* appear as the argument to React.forwardRef() or React.memo():
*/
if (node.isFunctionExpression() || node.isArrowFunctionExpression()) {
if (isForwardRefCallback(node) || isMemoCallback(node)) {
// As an added check we also look for hook invocations or JSX
return callsHooksOrCreatesJsx(node, hookPattern) ? 'Component' : null;
}
}
return null;
}
function skipNestedFunctions(
node: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
) {
return (
fn: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
): void => {
if (fn.node !== node.node) {
fn.skip();
}
};
}
function callsHooksOrCreatesJsx(
node: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
hookPattern: string | null,
): boolean {
let invokesHooks = false;
let createsJsx = false;
node.traverse({
JSX() {
createsJsx = true;
},
CallExpression(call) {
const callee = call.get('callee');
if (callee.isExpression() && isHook(callee, hookPattern)) {
invokesHooks = true;
}
},
ArrowFunctionExpression: skipNestedFunctions(node),
FunctionExpression: skipNestedFunctions(node),
FunctionDeclaration: skipNestedFunctions(node),
});
return invokesHooks || createsJsx;
}
function isNonNode(node?: t.Expression | null): boolean {
if (!node) {
return true;
}
switch (node.type) {
case 'ObjectExpression':
case 'ArrowFunctionExpression':
case 'FunctionExpression':
case 'BigIntLiteral':
case 'ClassExpression':
case 'NewExpression': // technically `new Array()` is legit, but unlikely
return true;
}
return false;
}
function returnsNonNode(
node: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
): boolean {
let returnsNonNode = false;
if (
// node.traverse#ArrowFunctionExpression isn't called for the root node
node.type === 'ArrowFunctionExpression' &&
node.node.body.type !== 'BlockStatement'
) {
returnsNonNode = isNonNode(node.node.body);
}
node.traverse({
ReturnStatement(ret) {
returnsNonNode = isNonNode(ret.node.argument);
},
// Skip traversing all nested functions and their return statements
ArrowFunctionExpression: skipNestedFunctions(node),
FunctionExpression: skipNestedFunctions(node),
FunctionDeclaration: skipNestedFunctions(node),
ObjectMethod: node => node.skip(),
});
return returnsNonNode;
}
/*
* Gets the static name of a function AST node. For function declarations it is
* easy. For anonymous function expressions it is much harder. If you search for
* `IsAnonymousFunctionDefinition()` in the ECMAScript spec you'll find places
* where JS gives anonymous function expressions names. We roughly detect the
* same AST nodes with some exceptions to better fit our use case.
*/
function getFunctionName(
path: NodePath<
t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
>,
): NodePath<t.Expression> | null {
if (path.isFunctionDeclaration()) {
const id = path.get('id');
if (id.isIdentifier()) {
return id;
}
return null;
}
let id: NodePath<t.LVal | t.Expression | t.PrivateName> | null = null;
const parent = path.parentPath;
if (parent.isVariableDeclarator() && parent.get('init').node === path.node) {
// const useHook = () => {};
id = parent.get('id');
} else if (
parent.isAssignmentExpression() &&
parent.get('right').node === path.node &&
parent.get('operator') === '='
) {
// useHook = () => {};
id = parent.get('left');
} else if (
parent.isProperty() &&
parent.get('value').node === path.node &&
!parent.get('computed') &&
parent.get('key').isLVal()
) {
/*
* {useHook: () => {}}
* {useHook() {}}
*/
id = parent.get('key');
} else if (
parent.isAssignmentPattern() &&
parent.get('right').node === path.node &&
!parent.get('computed')
) {
/*
* const {useHook = () => {}} = {};
* ({useHook = () => {}} = {});
*
* Kinda clowny, but we'd said we'd follow spec convention for
* `IsAnonymousFunctionDefinition()` usage.
*/
id = parent.get('left');
}
if (id !== null && (id.isIdentifier() || id.isMemberExpression())) {
return id;
} else {
return null;
}
}
function getFunctionReferencedBeforeDeclarationAtTopLevel(
program: NodePath<t.Program>,
fns: Array<CompileResult>,
): Set<CompileResult> {
const fnNames = new Map<string, {id: t.Identifier; fn: CompileResult}>(
fns
.map<[NodePath<t.Expression> | null, CompileResult]>(fn => [
getFunctionName(fn.originalFn),
fn,
])
.filter(
(entry): entry is [NodePath<t.Identifier>, CompileResult] =>
!!entry[0] && entry[0].isIdentifier(),
)
.map(entry => [entry[0].node.name, {id: entry[0].node, fn: entry[1]}]),
);
const referencedBeforeDeclaration = new Set<CompileResult>();
program.traverse({
TypeAnnotation(path) {
path.skip();
},
TSTypeAnnotation(path) {
path.skip();
},
TypeAlias(path) {
path.skip();
},
TSTypeAliasDeclaration(path) {
path.skip();
},
Identifier(id) {
const fn = fnNames.get(id.node.name);
// We're not tracking this identifier.
if (!fn) {
return;
}
/*
* We've reached the declaration, hoisting is no longer possible, stop
* checking for this component name.
*/
if (id.node === fn.id) {
fnNames.delete(id.node.name);
return;
}
const scope = id.scope.getFunctionParent();
/*
* A null scope means there's no function scope, which means we're at the
* top level scope.
*/
if (scope === null && id.isReferencedIdentifier()) {
referencedBeforeDeclaration.add(fn.fn);
}
},
});
return referencedBeforeDeclaration;
}
export function getReactCompilerRuntimeModule(
target: CompilerReactTarget,
): string {
if (target === '19') {
return 'react/compiler-runtime'; // from react namespace
} else if (target === '17' || target === '18') {
return 'react-compiler-runtime'; // npm package
} else {
CompilerError.invariant(
target != null &&
target.kind === 'donotuse_meta_internal' &&
typeof target.runtimeModule === 'string',
{
reason: 'Expected target to already be validated',
description: null,
loc: null,
suggestions: null,
},
);
return target.runtimeModule;
}
}