enable composing PositionalArgs (#896)

* enable composing PositionalArgs
* ExactValidArgs slated for removal
* tests and docs
* rename to MatchAll
This commit is contained in:
Nelz 2021-12-07 14:38:00 -08:00 committed by GitHub
parent 9e1d6f1c2a
commit 45e521ea93
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 62 additions and 0 deletions

12
args.go
View file

@ -107,3 +107,15 @@ func RangeArgs(min int, max int) PositionalArgs {
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
}
}

View file

@ -1,6 +1,7 @@
package cobra
import (
"fmt"
"strings"
"testing"
)
@ -243,3 +244,51 @@ func TestChildTakesArgs(t *testing.T) {
t.Fatalf("Unexpected error: %v", err)
}
}
func TestMatchAll(t *testing.T) {
// Somewhat contrived example check that ensures there are exactly 3
// arguments, and each argument is exactly 2 bytes long.
pargs := MatchAll(
ExactArgs(3),
func(cmd *Command, args []string) error {
for _, arg := range args {
if len([]byte(arg)) != 2 {
return fmt.Errorf("expected to be exactly 2 bytes long")
}
}
return nil
},
)
testCases := map[string]struct {
args []string
fail bool
}{
"happy path": {
[]string{"aa", "bb", "cc"},
false,
},
"incorrect number of args": {
[]string{"aa", "bb", "cc", "dd"},
true,
},
"incorrect number of bytes in one arg": {
[]string{"aa", "bb", "abc"},
true,
},
}
rootCmd := &Command{Use: "root", Args: pargs, Run: emptyRun}
for name, tc := range testCases {
t.Run(name, func(t *testing.T) {
_, err := executeCommand(rootCmd, tc.args...)
if err != nil && !tc.fail {
t.Errorf("unexpected: %v\n", err)
}
if err == nil && tc.fail {
t.Errorf("expected error")
}
})
}
}

View file

@ -315,6 +315,7 @@ The following validators are built in:
- `ExactArgs(int)` - the command will report an error if there are not exactly N positional args.
- `ExactValidArgs(int)` - the command will report an error if there are not exactly N positional args OR if there are any positional args that are not in the `ValidArgs` field of `Command`
- `RangeArgs(min, max)` - the command will report an error if the number of args is not between the minimum and maximum number of expected args.
- `MatchAll(pargs ...PositionalArgs)` - enables combining existing checks with arbitrary other checks (e.g. you want to check the ExactArgs length along with other qualities).
An example of setting the custom validator: