checkEvalAvailabilityOnceDev() — react Function Reference

Architecture documentation for the checkEvalAvailabilityOnceDev() function in ReactClientDebugConfigBrowser.js from the react codebase.

Function javascript BabelCompiler Validation

Entity Profile

BabelCompiler→ Validation→ checkEvalAvailabilityOnceDev() — react Function Reference

Dependency Diagram

graph TD
  d5b7bac9_0417_87ca_5130_2fb15f2659fa["checkEvalAvailabilityOnceDev()"]
  bf697f1b_c678_0add_eb55_93faf6e4002d["ReactClientDebugConfigBrowser.js"]
  d5b7bac9_0417_87ca_5130_2fb15f2659fa -->|defined in| bf697f1b_c678_0add_eb55_93faf6e4002d
  style d5b7bac9_0417_87ca_5130_2fb15f2659fa fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/react-client/src/ReactClientDebugConfigBrowser.js lines 11–36

export function checkEvalAvailabilityOnceDev(): void {
  if (__DEV__) {
    if (!hasConfirmedEval) {
      hasConfirmedEval = true;
      try {
        // eslint-disable-next-line no-eval
        (0, eval)('null');
      } catch {
        console.error(
          'eval() is not supported in this environment. ' +
            'If this page was served with a `Content-Security-Policy` header, ' +
            'make sure that `unsafe-eval` is included. ' +
            'React requires eval() in development mode for various debugging features ' +
            'like reconstructing callstacks from a different environment.\n' +
            'React will never use eval() in production mode',
        );
      }
    }
  } else {
    // These errors should never make it into a build so we don't need to encode them in codes.json
    // eslint-disable-next-line react-internal/prod-error-codes
    throw new Error(
      'checkEvalAvailabilityOnceDev should never be called in production mode. This is a bug in React.',
    );
  }
}