mergeOverlappingReactiveScopesHIR() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/HIR/MergeOverlappingReactiveScopesHIR.ts lines 105–136

export function mergeOverlappingReactiveScopesHIR(fn: HIRFunction): void {
  /**
   * Collect all scopes eagerly because some scopes begin before the first
   * instruction that references them (due to alignReactiveScopesToBlocks)
   */
  const scopesInfo = collectScopeInfo(fn);

  /**
   * Iterate through scopes and instructions to find which should be merged
   */
  const joinedScopes = getOverlappingReactiveScopes(fn, scopesInfo);

  /**
   * Merge scopes and rewrite all references
   */
  joinedScopes.forEach((scope, groupScope) => {
    if (scope !== groupScope) {
      groupScope.range.start = makeInstructionId(
        Math.min(groupScope.range.start, scope.range.start),
      );
      groupScope.range.end = makeInstructionId(
        Math.max(groupScope.range.end, scope.range.end),
      );
    }
  });
  for (const [place, originalScope] of scopesInfo.placeScopes) {
    const nextScope = joinedScopes.find(originalScope);
    if (nextScope !== null && nextScope !== originalScope) {
      place.identifier.scope = nextScope;
    }
  }
}