github.com/loggregator/cli@v6.33.1-0.20180224010324-82334f081791+incompatible/cf/flags/flags_usage.go (about) 1 package flags 2 3 import ( 4 "fmt" 5 "sort" 6 "strings" 7 ) 8 9 func (c *flagContext) ShowUsage(leadingSpace int) string { 10 displayFlags := flags{} 11 12 for _, f := range c.cmdFlags { 13 if !f.Visible() { 14 continue 15 } 16 17 d := flagPresenter{ 18 flagSet: f, 19 } 20 21 displayFlags = append(displayFlags, d) 22 } 23 24 return displayFlags.toString(strings.Repeat(" ", leadingSpace)) 25 } 26 27 type flagPresenter struct { 28 flagSet FlagSet 29 } 30 31 func (p *flagPresenter) line(l int) string { 32 flagList := p.flagList() 33 usage := p.usage() 34 spaces := strings.Repeat(" ", 6+(l-len(flagList))) 35 36 return strings.TrimRight(fmt.Sprintf("%s%s%s", flagList, spaces, usage), " ") 37 } 38 39 func (p *flagPresenter) flagList() string { 40 f := p.flagSet 41 var parts []string 42 43 if f.GetName() != "" { 44 parts = append(parts, fmt.Sprintf("--%s", f.GetName())) 45 } 46 47 if f.GetShortName() != "" { 48 parts = append(parts, fmt.Sprintf("-%s", f.GetShortName())) 49 } 50 51 return strings.Join(parts, ", ") 52 } 53 54 func (p *flagPresenter) usage() string { 55 return p.flagSet.String() 56 } 57 58 func (p *flagPresenter) comparableString() string { 59 if p.flagSet.GetName() != "" { 60 return p.flagSet.GetName() 61 } 62 63 return p.flagSet.GetShortName() 64 } 65 66 type flags []flagPresenter 67 68 func (f flags) Len() int { 69 return len(f) 70 } 71 72 func (f flags) Less(i, j int) bool { 73 return (f[i].comparableString() < f[j].comparableString()) 74 } 75 76 func (f flags) Swap(i, j int) { 77 f[i], f[j] = f[j], f[i] 78 } 79 80 func (f flags) toString(prefix string) string { 81 sort.Sort(f) 82 83 lines := make([]string, f.Len()) 84 maxLength := f.maxLineLength() 85 86 for i, l := range f { 87 lines[i] = fmt.Sprintf("%s%s", prefix, l.line(maxLength)) 88 } 89 90 return strings.Join(lines, "\n") 91 } 92 93 func (f flags) maxLineLength() int { 94 var l int 95 96 for _, x := range f { 97 98 lPrime := len(x.flagList()) 99 100 if lPrime > l { 101 l = lPrime 102 } 103 } 104 105 return l 106 }