extractManualMemoizationArgs() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/Inference/DropManualMemoization.ts lines 290–376

function extractManualMemoizationArgs(
  instr: TInstruction<CallExpression> | TInstruction<MethodCall>,
  kind: 'useCallback' | 'useMemo',
  sidemap: IdentifierSidemap,
  errors: CompilerError,
): {
  fnPlace: Place;
  depsList: Array<ManualMemoDependency> | null;
  depsLoc: SourceLocation | null;
} | null {
  const [fnPlace, depsListPlace] = instr.value.args as Array<
    Place | SpreadPattern | undefined
  >;
  if (fnPlace == null || fnPlace.kind !== 'Identifier') {
    errors.pushDiagnostic(
      CompilerDiagnostic.create({
        category: ErrorCategory.UseMemo,
        reason: `Expected a callback function to be passed to ${kind}`,
        description:
          kind === 'useCallback'
            ? 'The first argument to useCallback() must be a function to cache'
            : 'The first argument to useMemo() must be a function that calculates a result to cache',
        suggestions: null,
      }).withDetails({
        kind: 'error',
        loc: instr.value.loc,
        message:
          kind === 'useCallback'
            ? `Expected a callback function`
            : `Expected a memoization function`,
      }),
    );
    return null;
  }
  if (depsListPlace == null) {
    return {
      fnPlace,
      depsList: null,
      depsLoc: null,
    };
  }
  const maybeDepsList =
    depsListPlace.kind === 'Identifier'
      ? sidemap.maybeDepsLists.get(depsListPlace.identifier.id)
      : null;
  if (maybeDepsList == null) {
    errors.pushDiagnostic(
      CompilerDiagnostic.create({
        category: ErrorCategory.UseMemo,
        reason: `Expected the dependency list for ${kind} to be an array literal`,
        description: `Expected the dependency list for ${kind} to be an array literal`,
        suggestions: null,
      }).withDetails({
        kind: 'error',
        loc:
          depsListPlace?.kind === 'Identifier' ? depsListPlace.loc : instr.loc,
        message: `Expected the dependency list for ${kind} to be an array literal`,
      }),
    );
    return null;
  }
  const depsList: Array<ManualMemoDependency> = [];
  for (const dep of maybeDepsList.deps) {
    const maybeDep = sidemap.maybeDeps.get(dep.identifier.id);
    if (maybeDep == null) {
      errors.pushDiagnostic(
        CompilerDiagnostic.create({
          category: ErrorCategory.UseMemo,
          reason: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
          description: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
          suggestions: null,
        }).withDetails({
          kind: 'error',
          loc: dep.loc,
          message: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
        }),
      );
    } else {
      depsList.push(maybeDep);
    }
  }