shallowEqual() — react Function Reference

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

Function javascript BabelCompiler Optimization calls 1

Entity Profile

BabelCompiler→ Optimization→ shallowEqual() — react Function Reference

Dependency Diagram

graph TD
  32442e80_d840_f60a_a31a_ea0e39ac487a["shallowEqual()"]
  453d8884_196c_9b47_f492_31e5c07005e7["shallowEqual.js"]
  32442e80_d840_f60a_a31a_ea0e39ac487a -->|defined in| 453d8884_196c_9b47_f492_31e5c07005e7
  dab343e7_d491_ab84_5374_66898c315624["is()"]
  32442e80_d840_f60a_a31a_ea0e39ac487a -->|calls| dab343e7_d491_ab84_5374_66898c315624
  style 32442e80_d840_f60a_a31a_ea0e39ac487a fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/shared/shallowEqual.js lines 18–52

function shallowEqual(objA: mixed, objB: mixed): boolean {
  if (is(objA, objB)) {
    return true;
  }

  if (
    typeof objA !== 'object' ||
    objA === null ||
    typeof objB !== 'object' ||
    objB === null
  ) {
    return false;
  }

  const keysA = Object.keys(objA);
  const keysB = Object.keys(objB);

  if (keysA.length !== keysB.length) {
    return false;
  }

  // Test for A's keys different from B.
  for (let i = 0; i < keysA.length; i++) {
    const currentKey = keysA[i];
    if (
      !hasOwnProperty.call(objB, currentKey) ||
      // $FlowFixMe[incompatible-use] lost refinement of `objB`
      !is(objA[currentKey], objB[currentKey])
    ) {
      return false;
    }
  }

  return true;
}