Improve deepobject unmarshalling to support nullable.Nullable and encode.TextUnmarshaler

deepobject.go

@@ -2,6 +2,7 @@ package runtime
 
 import (
 	"bytes"
+	"encoding"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -55,8 +56,16 @@ func marshalDeepObject(in interface{}, path []string) ([]string, error) {
 		// into a deepObject style set of subscripts. [a, b, c] turns into
 		// [a][b][c]
 		prefix := "[" + strings.Join(path, "][") + "]"
+
+		var value string
+		if t == nil {
+			value = "null"
+		} else {
+			value = fmt.Sprintf("%v", t)
+		}
+
 		result = []string{
-			prefix + fmt.Sprintf("=%v", t),
+			prefix + fmt.Sprintf("=%s", value),
 		}
 	}
 	return result, nil
@@ -268,6 +277,7 @@ func assignPathValues(dst interface{}, pathValues fieldOrValue) error {
 				dst = reflect.Indirect(aPtr)
 			}
 			dst.Set(reflect.ValueOf(date))
+			return nil
 		}
 		if it.ConvertibleTo(reflect.TypeOf(time.Time{})) {
 			var tm time.Time
@@ -288,6 +298,13 @@ func assignPathValues(dst interface{}, pathValues fieldOrValue) error {
 				dst = reflect.Indirect(aPtr)
 			}
 			dst.Set(reflect.ValueOf(tm))
+			return nil
+		}
+		// For other struct types that implement TextUnmarshaler (e.g. uuid.UUID),
+		// use that for binding. This comes after the legacy Date/time.Time checks
+		// above which have special fallback format handling.
+		if tu, ok := v.Interface().(encoding.TextUnmarshaler); ok {
+			return tu.UnmarshalText([]byte(pathValues.value))
 		}
 		fieldMap, err := fieldIndicesByJSONTag(iv.Interface())
 		if err != nil {

deepobject_test.go

@@ -63,6 +63,7 @@ func TestDeepObject(t *testing.T) {
 	om := map[string]int{
 		"additional": 1,
 	}
+
 	d := MockBinder{Time: time.Date(2020, 2, 1, 0, 0, 0, 0, time.UTC)}
 
 	two := 2