@cirrusct/cli/src/parameters.ts

import { CliValue, CliCommandDefinitionParameter, CliValueValidatorFunction } from './types';
import { coerceCliValue, isFunction, isRegExp } from './utils';
import { isLVal } from '@babel/types';

export const getCommandDefinitionParameterValue = (
    value: CliValue,
    defParam: CliCommandDefinitionParameter,
    wasPassed = true
): CliValue => {
    let v = coerceCliValue(value || defParam.default, defParam.valueType);
    if (wasPassed && isFunction(defParam.transform)) {
        v = defParam.transform(v);
    }
    return v;
};

export const validateCommandDefinitionParameterValue = (
    value: CliValue,
    defParam: CliCommandDefinitionParameter
): boolean | string => {
    if (defParam.validate) {
        if (isFunction(defParam.valueType)) {
            const validator = defParam.validate as CliValueValidatorFunction;
            return validator(value);
        } else if (isRegExp(defParam.validate)) {
            const m = (defParam.validate as RegExp).exec(value as string);
            return !!m || `'${value}' fails RegExp validation: '${defParam.validate}'`;
        } else {
            console.assert(false);
            // should have been caught in def validation
        }
    }
    return true;
};