checkDCE() — react Function Reference

Architecture documentation for the checkDCE() function in unstable_testing.js from the react codebase.

Function javascript BabelCompiler Validation

Entity Profile

BabelCompiler→ Validation→ checkDCE() — react Function Reference

Dependency Diagram

graph TD
  596101d2_e32f_6bd8_1c60_30179530aa62["checkDCE()"]
  60f865c3_9388_bb11_6dd0_082c6affb77d["unstable_testing.js"]
  596101d2_e32f_6bd8_1c60_30179530aa62 -->|defined in| 60f865c3_9388_bb11_6dd0_082c6affb77d
  style 596101d2_e32f_6bd8_1c60_30179530aa62 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/react-dom/npm/unstable_testing.js lines 3–29

function checkDCE() {
  /* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
  if (
    typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ === 'undefined' ||
    typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.checkDCE !== 'function'
  ) {
    return;
  }
  if (process.env.NODE_ENV !== 'production') {
    // This branch is unreachable because this function is only called
    // in production, but the condition is true only in development.
    // Therefore if the branch is still here, dead code elimination wasn't
    // properly applied.
    // Don't change the message. React DevTools relies on it. Also make sure
    // this message doesn't occur elsewhere in this function, or it will cause
    // a false positive.
    throw new Error('^_^');
  }
  try {
    // Verify that the code above has been dead code eliminated (DCE'd).
    __REACT_DEVTOOLS_GLOBAL_HOOK__.checkDCE(checkDCE);
  } catch (err) {
    // DevTools shouldn't crash React, no matter what.
    // We should still report in case we break this code.
    console.error(err);
  }
}