Fix message channel usage in few tests. #14557
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Channels don't preserve Map and List type arguments: Map<String, Object> arrives as Map<dynamic, dynamic> to the receiver. In Dart 2 type system dynamic no longer serves as bottom type so Map<dynamic, dynamic> can't be assign to a variable of type Map<String, dynamic>. Issue flutter#14556
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LGTM |
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Can we preserve the types somehow? |
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Depends on the level of preservation we want to achieve - we need to be predictable. Some types are easy to preserve, e.g. Once we decide on a set of types to preserve another question becomes: how to write that in Dart without mirrors. Writing code like this in the serializer: if (x is Map<String, int>) {
} else if (x is Map<int, String>) {
} else if (x is Map<int, int>) {
} else if (x is Map<int, List>) {
} else ...is not exactly, ahm, pleasant. I do think that we might want to make channels more strongly typed in the end, but it requires considerable design and engineering effort. |
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The API has a fixed set of types it supports, right? It's not arbitrary types. So at least it would be bounded. I guess there's no way to construct a Map from Type objects, which is what we'd really need to keep this sane... |
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@Hixie it's not really bounded because types can be nested, e.g.
Exactly. Also you might want to be able to construct types from other types to create arbitrary nested types like the one I showed above. |
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Fair enough. We should consider this feedback for a feature request for Dart. (Let me know if you'd like me to file the bug, or if you want to file it, add a link to it here. Thanks!) |
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I will take a stub at filing a bug. I will link it to #14556 when I do. |
* master: (88 commits) Upgrade dartdoc to 0.16.0. (flutter#14602) Reduce noise in xcodebuild stdout (flutter#14586) Add annotations to ignore analyzer errors on pre-dev.22 SDKs (flutter#14599) Roll engine to 337764e (flutter#14597) Roll engine with rolled dart (flutter#14538) Upgrade packages (flutter#14588) Change GlobalObjectKey.toString to strip away State<StatefulWidget>. (flutter#14558) Disable selection of the Android ARM64 target platform based on the attached device (flutter#14581) Add a flutter run option that can override the default target platform (flutter#14537) Fix message channel usage in few tests. (flutter#14557) Update documentation on how to test flutter_tools (flutter#14567) Fix text_style_text.dart to be Dart 2 compliant. (flutter#14559) Hide the NDK warning that should never happen with a regexp (flutter#14503) Fix iOS build which broke after the change to fuse --strong option into --preview-dart-2. Mark run_machine_concurrent_hot_reload as flaky (flutter#14563) Fuse --strong into --preview-dart-2 option. Partially fix Dart 2 issues in animated_icons.test. (flutter#14531) Strong mode fixes in tests (flutter#14520) Fix typo. Fix issues. ...
Channels don't preserve Map and List type arguments: Map<String, Object> arrives as Map<dynamic, dynamic> to the receiver. In Dart 2 type system dynamic no longer serves as bottom type so Map<dynamic, dynamic> can't be assign to a variable of type Map<String, dynamic>. Issue flutter#14556
Channels don't preserve Map and List type arguments: Map<String, Object>
arrives as Map<dynamic, dynamic> to the receiver.
In Dart 2 type system dynamic no longer serves as bottom type so
Map<dynamic, dynamic> can't be assign to a variable of type
Map<String, dynamic>.
Issue #14556