func TestDecode_NilValue(t *testing.T) {
	t.Parallel()
	tests := []struct {
		name       string
		in         interface{}
		target     interface{}
		out        interface{}
		metaKeys   []string
		metaUnused []string
	}{
		{
			"all nil",
			&map[string]interface{}{
				"vfoo":   nil,
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{},
		},
		{
			"partial nil",
			&map[string]interface{}{
				"vfoo":   "baz",
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "baz", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{},
		},
		{
			"partial decode",
			&map[string]interface{}{
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "foo", Vother: nil},
			[]string{"Vother"},
			[]string{},
		},
		{
			"unused values",
			&map[string]interface{}{
				"vbar":   "bar",
				"vfoo":   nil,
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{"vbar"},
		},
		{
			"map interface all nil",
			&map[interface{}]interface{}{
				"vfoo":   nil,
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{},
		},
		{
			"map interface partial nil",
			&map[interface{}]interface{}{
				"vfoo":   "baz",
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "baz", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{},
		},
		{
			"map interface partial decode",
			&map[interface{}]interface{}{
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "foo", Vother: nil},
			[]string{"Vother"},
			[]string{},
		},
		{
			"map interface unused values",
			&map[interface{}]interface{}{
				"vbar":   "bar",
				"vfoo":   nil,
				"vother": nil,
			},
			&Map{Vfoo: "foo", Vother: map[string]string{"foo": "bar"}},
			&Map{Vfoo: "", Vother: nil},
			[]string{"Vfoo", "Vother"},
			[]string{"vbar"},
		},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			config := &DecoderConfig{
				Metadata:   new(Metadata),
				Result:     tc.target,
				ZeroFields: true,
			}
			decoder, err := NewDecoder(config)
			if err != nil {
				t.Fatalf("should not error: %s", err)
			}
			err = decoder.Decode(tc.in)
			if err != nil {
				t.Fatalf("should not error: %s", err)
			}
			if !reflect.DeepEqual(tc.out, tc.target) {
				t.Fatalf("%q: TestDecode_NilValue() expected: %#v, got: %#v", tc.name, tc.out, tc.target)
			}
			if !reflect.DeepEqual(tc.metaKeys, config.Metadata.Keys) {
				t.Fatalf("%q: Metadata.Keys mismatch expected: %#v, got: %#v", tc.name, tc.metaKeys, config.Metadata.Keys)
			}
			if !reflect.DeepEqual(tc.metaUnused, config.Metadata.Unused) {
				t.Fatalf("%q: Metadata.Unused mismatch expected: %#v, got: %#v", tc.name, tc.metaUnused, config.Metadata.Unused)
			}
		})
	}
}
GH-1, GH-10, GH-96
package mapstructure
import (
	"reflect"
	"testing"
	"time"
)