new.target undefined in ctor of CJS-nested `class X extends Error` — bundled-zod ZodError construction throws (config-schema error path)

[proggeramlug]

Summary

new.target is undefined inside the constructor of a class X extends Error declared inside a CJS module function (webpack-wrapper shape). Reading new.target.prototype throws.

This is the residual error-path blocker behind #6530: with the #6530 family fixed, Next.js's config-schema.js initializes and configSchema.safeParse(<valid config>) matches node — but any validation failure constructs the bundled zod's ZodError, whose constructor does const t = new.target.prototype → TypeError: Cannot read properties of undefined (reading 'prototype') (in the reduced repro below the message is undefined is not a constructor).

Repro

nt_err.cjs:

(() => {
  "use strict";
  var mods = {
    7: function (e, t) {
      class MyErr extends Error {
        constructor(issues) {
          super();
          this.issues = [];
          const p = new.target.prototype;
          if (Object.setPrototypeOf) Object.setPrototypeOf(this, p);
          this.name = "MyErr";
          this.issues = issues;
        }
      }
      t.MyErr = MyErr;
    },
  };
  var cache = {};
  function req(id) {
    if (cache[id]) return cache[id].exports;
    var m = (cache[id] = { exports: {} });
    mods[id].call(m.exports, m, m.exports);
    return m.exports;
  }
  module.exports = req(7);
})();

nt_err.ts:

const m = require("./nt_err.cjs");
const e = new m.MyErr([{ code: "x" }]);
console.log("name:", e.name, "issues:", JSON.stringify(e.issues));

node: name: MyErr issues: [{"code":"x"}]
perry: TypeError: undefined is not a constructor

Notes

• Pre-existing on main (reproduces with a main-built binary from before the bundled zod broken: optional().parse(undefined) throws, subclass identity collapses to ZodType — Next.js standalone boot blocker (config-schema init) #6530 fixes); unreachable in the Next.js boot path until bundled zod broken: optional().parse(undefined) throws, subclass identity collapses to ZodType — Next.js standalone boot blocker (config-schema init) #6530 landed because config-schema init died first.
• The codegen has new-target machinery (ctor_chain_uses_new_target gates js_new_target_set around the standalone-symbol ctor call in lower_call/new.rs), but the Error-subclass construction path for a CJS-nested class apparently never arms the cell.
• zod v3's ZodError is the production hit: every safeParse failure of Next's bundled zod constructs it, so invalid next.config.js values crash instead of reporting issues.