[pigeon] 0.2.0 Made null-safe generation the default, updated documentation

[gaaclarke]

Most of the work for 0.2.0 happened in an external contributors commit: #300

Pre-launch Checklist

• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide.
• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or Hixie said the PR is test-exempt.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy.
• I updated CHANGELOG.md to add a description of the change.
• I updated/added relevant documentation (doc comments with ///).
• I signed the CLA.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

[gaaclarke]

cc @Goddchen

[Goddchen]

@gaaclarke I have the fixes for the tests ready. But I don't know how I can get them in here. I tried checking out this repo/branch, committed them locally and tried to push them. But obviously I don't have write permission in here...

[Goddchen]

Hopefully this will to the trick: gaaclarke#1

[gaaclarke]

@Goddchen Thanks, that was kind of you. There is something weird going on with our CI. They are running locally fine and I can't retry. I'll keep your PR handy while I try to kick the bots.

[Goddchen]

What's going on with the checks? They seem to be hanging again?

[gaaclarke]

@Goddchen yea, I'm pinging a few people from my side to see if I can get it resolved.

[mitchross]

Seeing a crash running this.

pubspec

dev_dependencies:
flutter_test:
sdk: flutter
pigeon: git:
url: https://github.com/gaaclarke/packages.git
path: packages/pigeon
ref: pigeon-2-0-0`

flutter pub run pigeon --input pigeons/messages.dart --dart_null_safety
Unhandled exception:
Null check operator used on a null value
#0 generateJava (package:pigeon/java_generator.dart:248:49)
#1 Pigeon.run.<anonymous closure> (package:pigeon/pigeon_lib.dart:486:34)
#2 Pigeon._runGenerator (package:pigeon/pigeon_lib.dart:357:9)
#3 Pigeon.run (package:pigeon/pigeon_lib.dart:484:15)
<asynchronous suspension>
#4 main (file:///C:/Users/xxxx/AppData/Local/Temp/flutter_pigeon.94186523/_pigeon_temp_.dart:8:17) <asynchronous suspension>

[gaaclarke]

@mitchross Weird, it's working in the tests and when I try it out. Any idea what might be different for you?

$ git status
On branch pigeon-2-0-0
Your branch is up to date with 'origin/pigeon-2-0-0'.
$ pub run pigeon --input pigeons/message.dart --dart_null_safety --java_out foo.java --dart_out /dev/null 

What does your messages.dart file look like?

[alr2413]

@gaaclarke,
The same happens for me.
You just need to clone the flutter vlc player repository https://github.com/solid-software/flutter_vlc_player.git
and then inside the flutter_vlc_player folder run pigeon command.

[mitchross]

@gaaclarke,
The same happens for me.
You just need to clone the flutter vlc player repository https://github.com/solid-software/flutter_vlc_player.git
and then inside the flutter_vlc_player folder run pigeon command.

Also swap out the pubspec

dev_dependencies:
flutter_test:
sdk: flutter
pigeon:
git:
url: https://github.com/gaaclarke/packages.git
path: packages/pigeon
ref: pigeon-2-0-0`

[gaaclarke]

@mitchross@alr2413 Thanks, should be fixed now.

[xster]

add bug reference

[gaaclarke]

done

[xster]

Since it's a breaking change, add a banner at the top of this page too to describe where the break is

[xster]

We should caveat this a bit more clearly. If we're highlighting null safety more prominently, we should be clear there are 2 layers. There's the general null safety concept and there we're not doing too much yet. Things can't be defined as non-null and the nullable types aren't specifically annotated as so in kotlin and swift. There's also the Dart 2.12 null safety mechanism. We don't support non-null neither but we properly tag everything as nullable now.

[gaaclarke]

done

[Goddchen]

Failing after 1441m These checks are really screwed sometimes... I wish there was a simple "retry" button...

[gaaclarke]

Okay, published. Thanks for the patience.