visitScope() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/PruneNonReactiveDependencies.ts lines 93–118

  override visitScope(
    scopeBlock: ReactiveScopeBlock,
    state: ReactiveIdentifiers,
  ): void {
    this.traverseScope(scopeBlock, state);
    for (const dep of scopeBlock.scope.dependencies) {
      const isReactive = state.has(dep.identifier.id);
      if (!isReactive) {
        scopeBlock.scope.dependencies.delete(dep);
      }
    }
    if (scopeBlock.scope.dependencies.size !== 0) {
      /**
       * If any of a scope's dependencies are reactive, then all of its
       * outputs will re-evaluate whenever those dependencies change.
       * Mark all of the outputs as reactive to reflect the fact that
       * they may change in practice based on a reactive input.
       */
      for (const [, declaration] of scopeBlock.scope.declarations) {
        state.add(declaration.identifier.id);
      }
      for (const reassignment of scopeBlock.scope.reassignments) {
        state.add(reassignment.id);
      }
    }
  }