1.8.0 seems to introduce breaking change to custom decoders #498
Description
I have a custom decoder on a struct using the MapperValue interface. In 1.8.0, it appears that setting the target value (as seen in this example) doesn't update the value after parsing anymore, which I thought was the "proper" way to update the value. However, setting the value on the pointer receiver does work like in this example.
This is an example test that passes in 1.7.0, but not 1.8.0:
package decode_test
import (
"github.com/alecthomas/kong"
"gotest.tools/v3/assert"
"reflect"
"testing"
)
type CLI struct {
Foo Foo `env:"FOO"`
}
type Foo struct {
Bar string
}
func (f Foo) Decode(ctx *kong.DecodeContext) error {
// Decoding stuff...
ctx.Value.Target.Set(reflect.ValueOf(struct {
Bar string
}{"baz"}))
return nil
}
func Test_Decode(t *testing.T) {
c := &CLI{}
parser, err := kong.New(c)
assert.NilError(t, err)
t.Setenv("FOO", "")
_, err = parser.Parse([]string{})
assert.NilError(t, err)
assert.Equal(t, c.Foo.Bar, "baz")
}