Refactor RespondToFormatExceptionsTransformer (#60)
Remove some implicit dynamic.
- Add a generic type on the transformer.
- Use the original `channel` argument to access the `sink` rather than
assign to an intermediate transformed channel variable.
- Add a `test` argument to the `handleError` call to avoid having to
rethrow and change stack traces on other error types.
- Read the `message` and `source` fields from a variable which has a
static type.
- Add an explicit `dynamic` on one argument type which must be dynamic.
diff --git a/lib/src/utils.dart b/lib/src/utils.dart
index f8f776f..3f86f01 100644
--- a/lib/src/utils.dart
+++ b/lib/src/utils.dart
@@ -52,24 +52,20 @@
});
/// A transformer that sends error responses on [FormatException]s.
-final StreamChannelTransformer respondToFormatExceptions =
+final StreamChannelTransformer<Object, Object> respondToFormatExceptions =
_RespondToFormatExceptionsTransformer();
-/// The implementation of [respondToFormatExceptions].
class _RespondToFormatExceptionsTransformer
- implements StreamChannelTransformer {
+ implements StreamChannelTransformer<Object, Object> {
@override
- StreamChannel bind(StreamChannel channel) {
- var transformed;
- transformed = channel.changeStream((stream) {
- return stream.handleError((error) {
- if (error is! FormatException) throw error;
-
+ StreamChannel<Object> bind(StreamChannel<Object> channel) {
+ return channel.changeStream((stream) {
+ return stream.handleError((dynamic error) {
+ final formatException = error as FormatException;
var exception = RpcException(
- error_code.PARSE_ERROR, 'Invalid JSON: ${error.message}');
- transformed.sink.add(exception.serialize(error.source));
- });
+ error_code.PARSE_ERROR, 'Invalid JSON: ${formatException.message}');
+ channel.sink.add(exception.serialize(formatException.source));
+ }, test: (error) => error is FormatException);
});
- return transformed;
}
}
