What causes "vm.runInThisContext is not supported in Workers" in DIYgod/RSSHub?

Remove runInThisContext from Worker paths.

vm.runInThisContext is not supported in Workers

Error message

vm.runInThisContext is not supported in Workers

What it means

vmShim.runInThisContext() in lib/shims/node-module.ts throws. Workers disallow executing code in the current global context; this completes the set of vm execution functions that are import-safe but call-unsafe.

Source

Thrown at lib/shims/node-module.ts:71

    }
    runInNewContext() {
        throw new Error('vm.Script.runInNewContext is not supported in Workers');
    }
    runInThisContext() {
        throw new Error('vm.Script.runInThisContext is not supported in Workers');
    }
}

const vmShim = {
    createContext: (sandbox?: object) => sandbox || {},
    runInContext: () => {
        throw new Error('vm.runInContext is not supported in Workers');
    },
    runInNewContext: () => {
        throw new Error('vm.runInNewContext is not supported in Workers');
    },
    runInThisContext: () => {
        throw new Error('vm.runInThisContext is not supported in Workers');
    },
    Script: ScriptShim,
    isContext: () => false,
    compileFunction: () => {
        throw new Error('vm.compileFunction is not supported in Workers');
    },
};

// Child process shim (inline to avoid import cycle)
const child_process = {
    execSync: (_command: string): Buffer => Buffer.from(''),
    exec: () => {
        throw new Error('exec is not supported in Cloudflare Workers');
    },
    spawn: () => {
        throw new Error('spawn is not supported in Cloudflare Workers');
    },
    fork: () => {

View on GitHub (pinned to bed535e087)

Solutions

Remove runInThisContext from Worker paths.
Use bundler-time module resolution instead.
Run on Node if the behavior is required.

Example fix

// before
vm.runInThisContext(code);
// after
import * as mod from './mod'; // static, build-resolved

Defensive patterns

Strategy: validation

Validate before calling

const vmUsable = typeof process !== 'undefined' && !!process.versions?.node;
if (!vmUsable) {
  // skip vm.runInThisContext; use static imports
}

Type guard

function isVmShimError(e: unknown): e is Error {
  return e instanceof Error && /not supported in Workers/.test(e.message);
}

Try / catch

try {
  if (vmUsable) vm.runInThisContext(code);
  else return importedModule;
} catch (e) {
  if (isVmShimError(e)) return importedModule;
  throw e;
}

Prevention

Remove runtime self-eval from Worker code paths.
Resolve modules statically via the bundler.
Run require-hook style code only on Node.

When it happens

Trigger: Calling vm.runInThisContext(code) under Workers; some require-hook implementations and legacy eval wrappers.

Common situations: Migrated Node loaders; runtime self-modifying code; debugging hooks left enabled.

Related errors

AI-assisted analysis of DIYgod/RSSHub@bed535e087 (2026-08-12). Data as JSON: /api/errors/098406e39e2f74a6. Report an issue: GitHub.