alignObjectMethodScopes() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/AlignObjectMethodScopes.ts lines 56–100

export function alignObjectMethodScopes(fn: HIRFunction): void {
  // Handle inner functions: we assume that Scopes are disjoint across functions
  for (const [_, block] of fn.body.blocks) {
    for (const {value} of block.instructions) {
      if (
        value.kind === 'ObjectMethod' ||
        value.kind === 'FunctionExpression'
      ) {
        alignObjectMethodScopes(value.loweredFunc.func);
      }
    }
  }

  const scopeGroupsMap = findScopesToMerge(fn).canonicalize();
  /**
   * Step 1: Merge affected scopes to their canonical root.
   */
  for (const [scope, root] of scopeGroupsMap) {
    if (scope !== root) {
      root.range.start = makeInstructionId(
        Math.min(scope.range.start, root.range.start),
      );
      root.range.end = makeInstructionId(
        Math.max(scope.range.end, root.range.end),
      );
    }
  }

  /**
   * Step 2: Repoint identifiers whose scopes were merged.
   */
  for (const [_, block] of fn.body.blocks) {
    for (const {
      lvalue: {identifier},
    } of block.instructions) {
      if (identifier.scope != null) {
        const root = scopeGroupsMap.get(identifier.scope);
        if (root != null) {
          identifier.scope = root;
        }
        // otherwise, this identifier's scope was not affected by this pass
      }
    }
  }
}