github.com/hasnat/dolt/go@v0.0.0-20210628190320-9eb5d843fbb7/libraries/utils/argparser/option.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package argparser
    16  
    17  import (
    18  	"errors"
    19  	"strconv"
    20  )
    21  
    22  type OptionType int
    23  
    24  const (
    25  	OptionalFlag OptionType = iota
    26  	OptionalValue
    27  )
    28  
    29  type ValidationFunc func(string) error
    30  
    31  // Convenience validation function that asserts that an arg is an integer
    32  func isIntStr(str string) error {
    33  	_, err := strconv.ParseInt(str, 10, 32)
    34  	if err != nil {
    35  		return errors.New("error: \"" + str + "\" is not a valid int.")
    36  	}
    37  
    38  	return nil
    39  }
    40  
    41  // Convenience validation function that asserts that an arg is an unsigned integer
    42  func isUintStr(str string) error {
    43  	_, err := strconv.ParseUint(str, 10, 64)
    44  	if err != nil {
    45  		return errors.New("error: \"" + str + "\" is not a valid uint.")
    46  	}
    47  
    48  	return nil
    49  }
    50  
    51  // An Option encapsulates all the information necessary to represent and parse a command line argument.
    52  type Option struct {
    53  	// Long name for this Option, specified on the command line with --Name. Required.
    54  	Name string
    55  	// Abbreviated name for this Option, specified on the command line with -Abbrev. Optional.
    56  	Abbrev string
    57  	// Brief description of the Option.
    58  	ValDesc string
    59  	// The type of this option, either a flag or a value.
    60  	OptType OptionType
    61  	// Longer help text for the option.
    62  	Desc string
    63  	// Function to validate an Option after parsing, returning any error.
    64  	Validator ValidationFunc
    65  }