redux-form/src/readFields.js

A higher order component decorator for forms using Redux and React

import readField from './readField';
import write from './write';
import getValues from './getValues';
import removeField from './removeField';

/**
 * Reads props and generates (or updates) field structure
 */
const readFields = (props, previousProps, myFields, asyncValidate, isReactNative) => {
  const {fields, form, validate} = props;
  const previousFields = previousProps.fields;
  const values = getValues(fields, form);
  const syncErrors = validate(values, props);
  let errors = {};
  const formError = syncErrors._error || form._error;
  let allValid = !formError;
  let allPristine = true;
  const tally = field => {
    if (field.error) {
      errors = write(field.name, field.error, errors);
      allValid = false;
    }
    if (field.dirty) {
      allPristine = false;
    }
  };
  const fieldObjects = previousFields ? previousFields.reduce((accumulator, previousField) =>
    ~fields.indexOf(previousField) ? accumulator : removeField(accumulator, previousField),
    {...myFields}) : {...myFields};
  fields.forEach(name => {
    readField(form, name, undefined, fieldObjects, syncErrors, asyncValidate, isReactNative, props, tally);
  });
  Object.defineProperty(fieldObjects, '_meta', {
    value: {
      allPristine,
      allValid,
      values,
      errors,
      formError
    }
  });
  return fieldObjects;
};
export default readFields;