wehub-resource-sync
83 lines
2.3 KiB
Go
83 lines
2.3 KiB
Go
// Copyright 2019 Dolthub, Inc.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
// This file incorporates work covered by the following copyright and
|
|
// permission notice:
|
|
//
|
|
// Copyright 2016 Attic Labs, Inc. All rights reserved.
|
|
// Licensed under the Apache License, version 2.0:
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
// This is the Command struct used by the noms utility. It is packaged in a separate util can be used by other programs as well.
|
|
package util
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"os"
|
|
"strings"
|
|
|
|
flag "github.com/juju/gnuflag"
|
|
)
|
|
|
|
type Command struct {
|
|
// Run runs the command.
|
|
// The args are the arguments after the command name.
|
|
Run func(ctx context.Context, args []string) int
|
|
// Flag is a set of flags specific to this command.
|
|
Flags func() *flag.FlagSet
|
|
// UsageLine is the one-line usage message.
|
|
// The first word in the line is taken to be the command name.
|
|
UsageLine string
|
|
// Short is the short description shown in the 'help' output.
|
|
Short string
|
|
// Long is the long message shown in the 'help <this-command>' output.
|
|
Long string
|
|
// Nargs is the minimum number of arguments expected after flags, specific to this command.
|
|
Nargs int
|
|
}
|
|
|
|
// Name returns the command's name: the first word in the usage line.
|
|
func (nc *Command) Name() string {
|
|
name := nc.UsageLine
|
|
i := strings.Index(name, " ")
|
|
if i >= 0 {
|
|
name = name[:i]
|
|
}
|
|
return name
|
|
}
|
|
|
|
func countFlags(flags *flag.FlagSet) int {
|
|
if flags == nil {
|
|
return 0
|
|
} else {
|
|
n := 0
|
|
flags.VisitAll(func(f *flag.Flag) {
|
|
n++
|
|
})
|
|
return n
|
|
}
|
|
}
|
|
|
|
func (nc *Command) Usage() {
|
|
fmt.Fprintf(os.Stderr, "usage: %s\n\n", nc.UsageLine)
|
|
fmt.Fprintf(os.Stderr, "%s\n", strings.TrimSpace(nc.Long))
|
|
flags := nc.Flags()
|
|
if countFlags(flags) > 0 {
|
|
fmt.Fprintf(os.Stderr, "\noptions:\n")
|
|
flags.PrintDefaults()
|
|
}
|
|
os.Exit(1)
|
|
}
|