all: fix golangci-lint issues (#3064)

hscontrol/db/text_serialiser.go

@@ -3,12 +3,19 @@ package db
 import (
 	"context"
 	"encoding"
+	"errors"
 	"fmt"
 	"reflect"
 
 	"gorm.io/gorm/schema"
 )
 
+var (
+	errUnmarshalTextValue = errors.New("unmarshalling text value")
+	errUnsupportedType    = errors.New("unsupported type")
+	errTextMarshalerOnly  = errors.New("only encoding.TextMarshaler is supported")
+)
+
 // Got from https://github.com/xdg-go/strum/blob/main/types.go
 var textUnmarshalerType = reflect.TypeFor[encoding.TextUnmarshaler]()
 
@@ -42,22 +49,26 @@ func (TextSerialiser) Scan(ctx context.Context, field *schema.Field, dst reflect
 
 	if dbValue != nil {
 		var bytes []byte
+
 		switch v := dbValue.(type) {
 		case []byte:
 			bytes = v
 		case string:
 			bytes = []byte(v)
 		default:
-			return fmt.Errorf("unmarshalling text value: %#v", dbValue)
+			return fmt.Errorf("%w: %#v", errUnmarshalTextValue, dbValue)
 		}
 
 		if isTextUnmarshaler(fieldValue) {
 			maybeInstantiatePtr(fieldValue)
 			f := fieldValue.MethodByName("UnmarshalText")
 			args := []reflect.Value{reflect.ValueOf(bytes)}
+
 			ret := f.Call(args)
 			if !ret[0].IsNil() {
-				return decodingError(field.Name, ret[0].Interface().(error))
+				if err, ok := ret[0].Interface().(error); ok {
+					return decodingError(field.Name, err)
+				}
 			}
 
 			// If the underlying field is to a pointer type, we need to
@@ -73,7 +84,7 @@ func (TextSerialiser) Scan(ctx context.Context, field *schema.Field, dst reflect
 
 			return nil
 		} else {
-			return fmt.Errorf("unsupported type: %T", fieldValue.Interface())
+			return fmt.Errorf("%w: %T", errUnsupportedType, fieldValue.Interface())
 		}
 	}
 
@@ -87,8 +98,9 @@ func (TextSerialiser) Value(ctx context.Context, field *schema.Field, dst reflec
 		// always comparable, particularly when reflection is involved:
 		// https://dev.to/arxeiss/in-go-nil-is-not-equal-to-nil-sometimes-jn8
 		if v == nil || (reflect.ValueOf(v).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil()) {
-			return nil, nil
+			return nil, nil //nolint:nilnil // intentional: nil value for GORM serializer
 		}
+
 		b, err := v.MarshalText()
 		if err != nil {
 			return nil, err
@@ -96,6 +108,6 @@ func (TextSerialiser) Value(ctx context.Context, field *schema.Field, dst reflec
 
 		return string(b), nil
 	default:
-		return nil, fmt.Errorf("only encoding.TextMarshaler is supported, got %t", v)
+		return nil, fmt.Errorf("%w, got %T", errTextMarshalerOnly, v)
 	}
 }