从当前版本升级到最新版本时出现错误

Question

After i upgrade flutter from current version to latest inside my studio terminal by running flutter upgrade got following error.

The current Dart SDK version is 2.1.0-dev.0.0.flutter-be6309690f.

Because no versions of uri match >0.11.3 <0.12.0 and uri >=0.7.1 <0.11.3 requires SDK version >=0.8.10 <2.0.0 or >=2.0.0-dev.18 <2.0.0, uri >=0.7.1 <0.11.3-∞ or >0.11.3 <0.12.0 is forbidden.
And because uri 0.11.3 depends on quiver >=0.17.0 <0.30.0 and every version of flutter_test from sdk depends on quiver 2.0.0+1, flutter_test from sdk is incompatible with uri >=0.7.1 <0.12.0.
And because map_view 0.0.14 depends on uri ^0.11.1 and no versions of map_view match >0.0.14 <0.1.0, flutter_test from sdk is incompatible with map_view ^0.0.14.
So, because maskn depends on both map_view ^0.0.14 and flutter_test any from sdk, version solving failed.
pub get failed (1)

How can i solve this issue? Any way to downgrade from latest to my older version?

Answer 1

Adding this to pubpsec.yaml should work around until an uri version is released that supports Dart 2.0.0

dependency_overrides:
  quiver: ^2.0.0+1

Answer 2

There's this thread on github that closely mirrors your problem.

Basically you have to look for the offending plugin's .pubspec.yaml and edit it this way:

environment:
   sdk: ">=2.0.0-dev.58.0 <3.0.0"

Let me know if this is helpful.