diff options
Diffstat (limited to 'command.go')
| -rw-r--r-- | command.go | 170 |
1 files changed, 87 insertions, 83 deletions
@@ -2,118 +2,122 @@ package main import ( - "fmt" - "flag" - "os" + "flag" + "fmt" + "os" ) type ( - Command struct { - Use string // command name (used for matching) - Short string // a short description to display - Long string // a long help text - Example string // an example string - Run func(*Command, []string) // the command to run + Command struct { + Use string // command name (used for matching) + Short string // a short description to display + Long string // a long help text + Example string // an example string + Run func(*Command, []string) // the command to run - flagSet *flag.FlagSet // internal flagset with all flags - commands []*Command // the list of subcommands - } + flagSet *flag.FlagSet // internal flagset with all flags + commands []*Command // the list of subcommands + } ) // This function adds a new sub command. -func (c *Command) AddCommand(cmds... *Command) { - res := c.commands - for _, cmd := range cmds { - res = append(res, cmd) - } - c.commands = res +func (c *Command) AddCommand(cmds ...*Command) { + res := c.commands + for _, cmd := range cmds { + res = append(res, cmd) + } + c.commands = res } // Evaluate the arguments and call either the subcommand or parse it as flags. func (c *Command) eval(args []string) error { - var name string = "" - var rest []string = []string{} + var name string = "" + var rest []string = []string{} - if len(args) > 0 { - name = args[0] - } - if len(args) > 1 { - rest = args[1:] - } + if len(args) > 0 { + name = args[0] + } + if len(args) > 1 { + rest = args[1:] + } - if name == "help" { - c.Help(rest) - return nil - } + if name == "help" { + c.Help(rest) + return nil + } - for _, cmd := range c.commands { - if cmd.Use == name { - return cmd.eval(rest) - } - } - if err := c.Flags().Parse(args); err != nil { return err } - if c.Run != nil { - c.Run(c, rest) - } else { - c.Help(rest) - } - return nil + for _, cmd := range c.commands { + if cmd.Use == name { + return cmd.eval(rest) + } + } + if err := c.Flags().Parse(args); err != nil { + return err + } + if c.Run != nil { + c.Run(c, rest) + } else { + c.Help(rest) + } + return nil } // Execute the command. It will fetch os.Args[1:] itself. func (c *Command) Execute() error { - return c.eval(os.Args[1:]) + return c.eval(os.Args[1:]) } // Return the flagset currently in use. func (c *Command) Flags() *flag.FlagSet { - if c.flagSet == nil { - c.flagSet = flag.NewFlagSet(c.Use, flag.ContinueOnError) - } - return c.flagSet + if c.flagSet == nil { + c.flagSet = flag.NewFlagSet(c.Use, flag.ContinueOnError) + } + return c.flagSet } // Print the help for the current command or a subcommand. func (c *Command) Help(args []string) { - if len(args) > 0 { - for _, cmd := range c.commands { - if args[0] == cmd.Use { - cmd.Help([]string{}) - return - } - } - } - if c.Long != "" { fmt.Println(c.Long, "\n") } - c.Usage() + if len(args) > 0 { + for _, cmd := range c.commands { + if args[0] == cmd.Use { + cmd.Help([]string{}) + return + } + } + } + if c.Long != "" { + fmt.Println(c.Long, "\n") + } + c.Usage() } // Print the usage information. func (c *Command) Usage() { - usage := "" - if c.Use != "" { - usage = usage + " " + c.Use - } - if len(c.commands) > 0 { - usage = usage + " command" - } - if c.flagSet != nil { - usage = usage + " [flags]" - } - fmt.Printf("Usage: %s%s\n", os.Args[0], usage) + usage := "" + if c.Use != "" { + usage = usage + " " + c.Use + } + if len(c.commands) > 0 { + usage = usage + " command" + } + if c.flagSet != nil { + usage = usage + " [flags]" + } + fmt.Printf("Usage: %s%s\n", os.Args[0], usage) - if len(c.commands) > 0 { - fmt.Printf("\nwhere command is one of:\n") - for _, cmd := range c.commands { - fmt.Printf("\t%s\t\t%s\n", cmd.Use, cmd.Short) - } - } - if c.flagSet != nil { - fmt.Printf("\nwhere flags is any of:\n") - c.Flags().SetOutput(os.Stdout) - c.Flags().PrintDefaults() - } - if c.Example != "" { - fmt.Println("\nexample:") - fmt.Printf("\t%s\n", c.Example) - } + if len(c.commands) > 0 { + fmt.Printf("\nwhere command is one of:\n") + for _, cmd := range c.commands { + fmt.Printf("\t%s\t\t%s\n", cmd.Use, cmd.Short) + } + } + if c.flagSet != nil { + fmt.Printf("\nwhere flags is any of:\n") + c.Flags().SetOutput(os.Stdout) + c.Flags().PrintDefaults() + } + if c.Example != "" { + fmt.Println("\nexample:") + fmt.Printf("\t%s\n", c.Example) + } } |