inferDependencies() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/Inference/InferEffectDependencies.ts lines 588–637

function inferDependencies(
  fnInstr: TInstruction<FunctionExpression>,
  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
  processedInstrsInOptional: ReadonlySet<Instruction | Terminal>,
): Set<ReactiveScopeDependency> {
  const fn = fnInstr.value.loweredFunc.func;
  const context = new DependencyCollectionContext(
    new Set(),
    temporaries,
    processedInstrsInOptional,
  );
  for (const dep of fn.context) {
    context.declare(dep.identifier, {
      id: makeInstructionId(0),
      scope: empty(),
    });
  }
  const placeholderScope: ReactiveScope = {
    id: makeScopeId(0),
    range: {
      start: fnInstr.id,
      end: makeInstructionId(fnInstr.id + 1),
    },
    dependencies: new Set(),
    reassignments: new Set(),
    declarations: new Map(),
    earlyReturnValue: null,
    merged: new Set(),
    loc: GeneratedSource,
  };
  context.enterScope(placeholderScope);
  inferDependenciesInFn(fn, context, temporaries);
  context.exitScope(placeholderScope, false);
  const resultUnfiltered = context.deps.get(placeholderScope);
  CompilerError.invariant(resultUnfiltered != null, {
    reason:
      '[InferEffectDependencies] Internal invariant broken: missing scope dependencies',
    loc: fn.loc,
  });

  const fnContext = new Set(fn.context.map(dep => dep.identifier.id));
  const result = new Set<ReactiveScopeDependency>();
  for (const dep of resultUnfiltered) {
    if (fnContext.has(dep.identifier.id)) {
      result.add(dep);
    }
  }

  return result;
}