Allow all values to be pointers

This solves the issue of whether the field was populated or not, at the
expense of some horrible memory patterns. But on the plus side it
doesn't require any extra API so we might as well allow it.

1 files changed, 18 insertions, 9 deletions

diff --git a/ccl.go b/ccl.go
index 521fbba..fe67a72 100644
--- a/ccl.go
+++ b/ccl.go
@@ -592,6 +592,16 @@ func (p *parser) parse() (map[string]any, error) {
 	}
 }
 
+func setPtr(val reflect.Value) reflect.Value {
+	if val.Kind() != reflect.Pointer {
+		return val
+	}
+	if val.IsNil() {
+		val.Set(reflect.New(val.Type().Elem()))
+	}
+	return val.Elem()
+}
+
 func intLimits(kind reflect.Kind) (min, max uint64, ok bool) {
 	switch kind {
 	case reflect.Int:
@@ -622,6 +632,7 @@ func intLimits(kind reflect.Kind) (min, max uint64, ok bool) {
 func unpackVal(fieldVal reflect.Value, fieldMap map[structField]int, val any, field string) error {
 	switch val := val.(type) {
 	case bool:
+		fieldVal := setPtr(fieldVal)
 		switch fieldVal.Kind() {
 		case reflect.Bool:
 			fieldVal.SetBool(val)
@@ -641,6 +652,7 @@ func unpackVal(fieldVal reflect.Value, fieldMap map[structField]int, val any, fi
 			return fmt.Errorf("field %q should have type bool", field)
 		}
 	case *integer:
+		fieldVal := setPtr(fieldVal)
 		switch fieldVal.Kind() {
 		case reflect.Float32, reflect.Float64:
 			fieldVal.SetFloat(float64(val.sgn) * float64(val.n))
@@ -659,6 +671,7 @@ func unpackVal(fieldVal reflect.Value, fieldMap map[structField]int, val any, fi
 			fieldVal.SetInt(int64(val.sgn) * int64(val.n))
 		}
 	case float64:
+		fieldVal := setPtr(fieldVal)
 		switch fieldVal.Kind() {
 		case reflect.Float32, reflect.Float64:
 			fieldVal.SetFloat(float64(val))
@@ -675,10 +688,11 @@ func unpackVal(fieldVal reflect.Value, fieldMap map[structField]int, val any, fi
 		if unmarshaler, ok := fieldVal.Addr().Interface().(encoding.TextUnmarshaler); ok {
 			return unmarshaler.UnmarshalText([]byte(val))
 		}
+		fieldVal := setPtr(fieldVal)
 		switch {
 		case fieldVal.Kind() == reflect.String:
 			fieldVal.SetString(val)
-		case fieldVal.Kind() == reflect.Slice && fieldVal.Type().Elem() == reflect.TypeFor[byte]():
+		case fieldVal.Type() == reflect.TypeFor[[]byte]():
 			b, err := base64.StdEncoding.DecodeString(val)
 			if err != nil {
 				return fmt.Errorf("field %q: bad base64", field)
@@ -688,15 +702,10 @@ func unpackVal(fieldVal reflect.Value, fieldMap map[structField]int, val any, fi
 			return fmt.Errorf("field %q should have type string (got %s)", field, fieldVal.Type())
 		}
 	case map[string]any:
-		if !(fieldVal.Kind() == reflect.Struct || fieldVal.Kind() == reflect.Pointer && fieldVal.Type().Elem().Kind() == reflect.Struct) {
+		fieldVal := setPtr(fieldVal)
+		if fieldVal.Kind() != reflect.Struct {
 			return fmt.Errorf("field %q should have type struct (got %s)", field, fieldVal.Type())
 		}
-		if fieldVal.Kind() == reflect.Pointer {
-			if fieldVal.IsNil() {
-				fieldVal.Set(reflect.New(fieldVal.Type().Elem()))
-			}
-			fieldVal = fieldVal.Elem()
-		}
 		if err := unpackStruct(fieldVal, fieldMap, val); err != nil {
 			return err
 		}
@@ -715,7 +724,7 @@ func unpackStruct(out reflect.Value, fieldMap map[structField]int, msg map[strin
 			return fmt.Errorf("no field named %q", field)
 		}
 		fieldVal := out.Field(fieldIdx)
-		if fieldVal.Kind() == reflect.Slice && fieldVal.Type().Elem() != reflect.TypeFor[byte]() {
+		if fieldVal.Kind() == reflect.Slice && fieldVal.Type() != reflect.TypeFor[[]byte]() {
 			var vals []any
 			if l, ok := val.([]any); ok {
 				vals = l