This repository has been archived by the owner on Feb 17, 2020. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 7
/
subcommand.go
200 lines (156 loc) · 3.56 KB
/
subcommand.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
package flag
import (
"fmt"
"io"
"os"
"sort"
"strings"
)
type ParentCommand struct {
Usage func()
name string
output io.Writer
subCommand map[string]*subCommand
subCommand2 map[string]*subCommand
args []string
maxName int
}
type subCommand struct {
Name string
Usage string
SubProcess func()
}
func NewParentCommand(name string) *ParentCommand {
p := &ParentCommand{
name: name,
}
p.Usage = p.defaultUsage
p.subCommand = make(map[string]*subCommand, 3)
p.subCommand2 = make(map[string]*subCommand, 3)
return p
}
func (p *ParentCommand) sortSubUsage() []*subCommand {
list := make([]string, len(p.subCommand))
i := 0
for _, sub := range p.subCommand {
list[i] = sub.Name
i++
}
sort.Strings(list)
result := make([]*subCommand, len(list))
for i, name := range list {
result[i] = p.subCommand[name]
}
return result
}
func (p *ParentCommand) PrintDefaults() {
subCommand := p.sortSubUsage()
for _, sub := range subCommand {
name := sub.Name
if len(name) > 0 {
name = " " + name + " " + strings.Repeat(" ", p.maxName-len(name)) + sub.Usage
}
fmt.Fprint(p.Output(), name, "\n")
}
}
func (p *ParentCommand) defaultUsage() {
if p.name == "" {
fmt.Fprintf(p.Output(), "Usage:\n")
} else {
fmt.Fprintf(p.Output(), "Usage of %s:\n", p.name)
}
p.PrintDefaults()
}
func (p *ParentCommand) Output() io.Writer {
if p.output == nil {
return os.Stderr
}
return p.output
}
func (p *ParentCommand) SetOutput(output io.Writer) {
p.output = output
}
func (p *ParentCommand) saveSubCommand(sub map[string]*subCommand, name string, usage string, subProcess func()) {
_, alreadythere := sub[name]
if alreadythere {
msg := ""
if p.name == "" {
msg = fmt.Sprintf("subcommand redefined: %s", name)
} else {
msg = fmt.Sprintf("%s subcommand redefined: %s", p.name, name)
}
fmt.Fprintln(p.Output(), msg)
panic(msg)
}
if p.maxName < len(name) {
p.maxName = len(name)
}
sub[name] = &subCommand{Name: name, Usage: usage, SubProcess: subProcess}
}
func (p *ParentCommand) SubCommand(name string, usage string, subProcess func()) {
names := strings.Split(name, ",")
if len(names) > 1 {
for k, _ := range names {
names[k] = strings.TrimSpace(names[k])
}
sort.Slice(names, func(i, j int) bool {
return len(names[i]) < len(names[j])
})
name = strings.Join(names, ", ")
}
p.saveSubCommand(p.subCommand, name, usage, subProcess)
for _, name := range names {
p.saveSubCommand(p.subCommand2, name, usage, subProcess)
}
}
func (p *ParentCommand) Args() []string { return p.args }
func (p *ParentCommand) usage() {
if p.Usage == nil {
p.defaultUsage()
} else {
p.Usage()
}
}
func (p *ParentCommand) parseOne() (bool, error) {
if len(p.args) == 0 {
return false, nil
}
s := p.args[0]
numMinuses := 0
if s[0] == '-' {
numMinuses++
if len(s) >= 2 && s[1] == '-' {
numMinuses++
}
}
name := s[numMinuses:]
m := p.subCommand
sub, alreadythere := m[name]
if !alreadythere {
if name == "h" || name == "help" {
p.usage()
return false, ErrHelp
}
sub, alreadythere = p.subCommand2[name]
if !alreadythere {
return false, p.failf("subcommand provided but not defined: -%s", name)
}
}
p.args = p.args[1:]
sub.SubProcess()
return true, nil
}
func (p *ParentCommand) failf(format string, a ...interface{}) error {
err := fmt.Errorf(format, a...)
fmt.Fprintln(p.Output(), err)
p.usage()
return err
}
func (p *ParentCommand) Parse(arguments []string) error {
p.args = arguments
for {
_, err := p.parseOne()
return err
}
return nil
}