cobra/args.go

145 lines
4.5 KiB
Go

// Copyright 2013-2023 The Cobra Authors
//
// 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.
package cobra
import (
"fmt"
"strings"
)
type PositionalArgs func(cmd *Command, args []string) error
// legacyArgs validation has the following behaviour:
// - root commands with no subcommands can take arbitrary arguments
// - root commands with subcommands will do subcommand validity checking
// - subcommands will always accept arbitrary arguments
func legacyArgs(cmd *Command, args []string) error {
// no subcommand, always take args
if !cmd.HasSubCommands() {
return nil
}
// root command with subcommands, do subcommand checking.
if !cmd.HasParent() && len(args) > 0 {
return fmt.Errorf("unknown command %q for %q%s", args[0], cmd.CommandPath(), cmd.findSuggestions(args[0]))
}
return nil
}
// NoArgs returns an error if any args are included.
func NoArgs(cmd *Command, args []string) error {
if len(args) > 0 {
return fmt.Errorf("unknown command %q for %q", args[0], cmd.CommandPath())
}
return nil
}
// OnlyValidArgs returns an error if there are any positional args that are not in
// the `ValidArgs` field of `Command`
func OnlyValidArgs(cmd *Command, args []string) error {
if len(cmd.ValidArgs) > 0 {
// Remove any description that may be included in ValidArgs.
// A description is following a tab character.
validArgs := make([]string, 0, len(cmd.ValidArgs))
for _, v := range cmd.ValidArgs {
validArgs = append(validArgs, strings.SplitN(v, "\t", 2)[0])
}
for _, v := range args {
if !stringInSlice(v, validArgs) {
return fmt.Errorf("invalid argument %q for %q%s", v, cmd.CommandPath(), cmd.findSuggestions(args[0]))
}
}
}
return nil
}
// ArbitraryArgs never returns an error.
func ArbitraryArgs(cmd *Command, args []string) error {
return nil
}
// MinimumNArgs returns an error if there is not at least N args.
func MinimumNArgs(n int) PositionalArgs {
return func(cmd *Command, args []string) error {
if len(args) < n {
return fmt.Errorf("requires at least %d arg(s), only received %d", n, len(args))
}
return nil
}
}
// MaximumNArgs returns an error if there are more than N args.
func MaximumNArgs(n int) PositionalArgs {
return func(cmd *Command, args []string) error {
if len(args) > n {
return fmt.Errorf("accepts at most %d arg(s), received %d", n, len(args))
}
return nil
}
}
// ExactArgs returns an error if there are not exactly n args.
func ExactArgs(n int) PositionalArgs {
return func(cmd *Command, args []string) error {
if len(args) != n {
return fmt.Errorf("accepts %d arg(s), received %d", n, len(args))
}
return nil
}
}
// RangeArgs returns an error if the number of args is not within the expected range.
func RangeArgs(min int, max int) PositionalArgs {
return func(cmd *Command, args []string) error {
if len(args) < min || len(args) > max {
return fmt.Errorf("accepts between %d and %d arg(s), received %d", min, max, len(args))
}
return nil
}
}
// MatchAll allows combining several PositionalArgs to work in concert.
func MatchAll(pargs ...PositionalArgs) PositionalArgs {
return func(cmd *Command, args []string) error {
for _, parg := range pargs {
if err := parg(cmd, args); err != nil {
return err
}
}
return nil
}
}
// ExactValidArgs returns an error if there are not exactly N positional args OR
// there are any positional args that are not in the `ValidArgs` field of `Command`
//
// Deprecated: use MatchAll(ExactArgs(n), OnlyValidArgs) instead
func ExactValidArgs(n int) PositionalArgs {
return MatchAll(ExactArgs(n), OnlyValidArgs)
}
// WithUsage wraps another PositionalArgs function. If the function fails
// (returns a non-nil error), the error is supplemented with the command's
// usage message, providing the user with the information required to run the
// command correctly.
func WithUsage(wrapped PositionalArgs) PositionalArgs {
return func(cmd *Command, args []string) error {
if err := wrapped(cmd, args); err != nil {
return fmt.Errorf("%w\n\n%s", err, cmd.UsageString())
}
return nil
}
}