[facebook/react] [Compiler Bug]: constant gets memoized with a wrong dependency

### ROOT CAUSE The issue arises because the React compiler's memoization mechanism incorrectly includes the `date` prop as a dependency for the `formatter` constant. This happens due to flawed dependency tracking in the compiler. The `formatter` is defined outside the conditional block but is used inside it, causing the compiler to mistakenly include `date` as a dependency. This leads to unnecessary re-renders and incorrect memoization. ### CODE FIX To fix this, modify the compiler's dependency tracking to properly analyze constant expressions. Specifically, ensure that constants defined outside conditionals and not dependent on component variables are memoized without including unnecessary dependencies. ```typescript // Pseudo-code for the compiler fix function analyzeDependencies(node, componentVariables) { // Check if the node is a constant expression (e.g., new Intl.DateTimeFormat('en-US')) if (node.type === 'ExpressionStatement' && node.expression.type === 'AssignmentPattern') { const constantValue = node.expression.right; // Check if the constantValue depends on any component variable if (!dependsOnComponentVariable(constantValue, componentVariables)) { // Memoize without any dependencies return []; } } // Fallback to normal dependency tracking return getNormalDependencies(node); } function dependsOnComponentVariable(node, componentVariables) { // Traverse the AST of the node and check for any references to component variables // If found, return true; otherwise, false. } ``` This fix ensures that constants like `formatter` are memoized with an empty dependency array if they don't depend on any component variables, preventing incorrect memoization and re-renders.