Allow upcoming package:collection version 2.x

[oprypin]

There will not be a breaking change in package:collection that concerns this package, but currently due to a circular dependency it's not even possible to bump said package's version to 2.0.

• See the CI failure in Remove IterableExtensions that have exact equivalents in the SDK collection#331

$ dart pub get
Resolving dependencies...
Because test >=1.16.0 depends on typed_data ^1.3.0 which depends on collection ^1.15.0, test >=1.16.0 requires collection ^1.15.0.
So, because collection depends on test ^1.16.0 and collection is 2.0.0-wip, version solving failed.

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[kevmoo]

What's the story here?

[oprypin]

There will not be a breaking change in package:collection that concerns this package, but currently due to a circular dependency it's not even possible to bump said package's version to 2.0.

• See the CI failure in Remove IterableExtensions that have exact equivalents in the SDK collection#331

$ dart pub get
Resolving dependencies...
Because test >=1.16.0 depends on typed_data ^1.3.0 which depends on collection ^1.15.0, test >=1.16.0 requires collection ^1.15.0.
So, because collection depends on test ^1.16.0 and collection is 2.0.0-wip, version solving failed.

[devoncarew]

collection only depends on test through a dev_dependency; it would be possible to do dependency_override of typed_data in package collection's pubspec, which would allow its CI to complete. That would mean we wouldn't have to proactively publish a version of typed_data which allows for an unpublished major version of collection.

[oprypin]

Thanks @devoncarew. But maybe this is still simpler - why not make a proactive release? A release that increases the version range would have to be done right away anyway.