Function ForStatement

tools/acorn-optimizer.mjs:233–239

(node, c)

    function cleanUp(ast, names) {
      recursiveWalk(ast, {
        ForStatement(node, c) {
          visitChildren(node, c);
          // If we had `for (var x = ...; ...)` and we removed `x`, we need to change to `for (; ...)`.
          if (node.init?.type === 'EmptyStatement') {
            node.init = null;
          }
        },
        ForInStatement(node, c) {
          // We can't remove the var in a for-in, as that would result in an invalid syntax. Skip the LHS.
          c(node.right);