github.com/xfond/eth-implementation@v1.8.9-0.20180514135602-f6bc65fc6811/common/format.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package common
    18  
    19  import (
    20  	"fmt"
    21  	"regexp"
    22  	"strings"
    23  	"time"
    24  )
    25  
    26  // PrettyDuration is a pretty printed version of a time.Duration value that cuts
    27  // the unnecessary precision off from the formatted textual representation.
    28  type PrettyDuration time.Duration
    29  
    30  var prettyDurationRe = regexp.MustCompile(`\.[0-9]+`)
    31  
    32  // String implements the Stringer interface, allowing pretty printing of duration
    33  // values rounded to three decimals.
    34  func (d PrettyDuration) String() string {
    35  	label := fmt.Sprintf("%v", time.Duration(d))
    36  	if match := prettyDurationRe.FindString(label); len(match) > 4 {
    37  		label = strings.Replace(label, match, match[:4], 1)
    38  	}
    39  	return label
    40  }