Migrated packages can't be successfully added to deps, even if in the allow list

[jakemac53]

See my pending cl here to pull in the migrated fixnum, for nnbd strong mode benchmarks https://dart-review.googlesource.com/c/sdk/+/150170.

There are some build actions that appear to not be picking up the correct .dart_tool/package_config.json file, or something along those lines.

[jakemac53]

cc @franklinyow we can't publish any of these packages until we have an sdk where they are in the allow list, so this is a blocker for flutter depending on any NNBD migrated packages (and thus a blocker for the flutter tech preview)

[franklinyow]

@leafpetersen

[jakemac53]

Note that this is also blocking all packages developed in the sdk from migrating to nnbd (meta, js, are important ones)

[leafpetersen]

@nshahan does dartdevc correctly handle package_config.json yet?

[leafpetersen]

@johnniwinther is there any work required from the back ends to make the allow list work?

[nshahan]

@nshahan does dartdevc correctly handle package_config.json yet?

We didn't implement any handling of the package_config.json file in DDC. If we need to pass some information to the CFE we can do that but I'll wait to hear what Johnni says.

[leafpetersen]

@nshahan suggested the possibility that the error is from the pre-built sdk that is checked in rather than from dartdevc. @jakemac53 with your CL , if you try to run dartdevc.dart with the version of dart from the pre-built sdk, do you see this error? If so, this is the problem.

[leafpetersen]

Ok, that's the issue. If I patch in the CL from @jakemac53, gclient sync, build and then try running with the local build and the pre-built I get the following:

leafp-macbookpro:sdk leafp$ ./xcodebuild/ReleaseX64/dart-sdk/bin/dart pkg/dev_compiler/bin/dartdevc.dart 
Please specify the output file location. For example:
    -o PATH/TO/OUTPUT_FILE.js
leafp-macbookpro:sdk leafp$ ./tools/sdks/dart-sdk/bin/dart pkg/dev_compiler/bin/dartdevc.dart 
third_party/pkg/fixnum/lib/src/int64.dart:446:10: Error: This requires the 'non-nullable' language feature to be enabled.
Try updating your pubspec.yaml to set the minimum SDK constraint to 2.9 or higher, and running 'pub get'.
    Int64? o;
         ^

@athomas I think we just need a new prebuilt SDK checked in.

[jakemac53]

Sounds good, are we going to have to do this for every package we want to migrate in? Should we try to do them all in one shot then?

[sigmundch]

This should only affect packages that are indirectly used by dartdevc. My guess is that most of these are indirect dependencies from using bazel_worker.

If the whitelist already includes all those dependencies already, I expect this would be a one-time thing. A prebuild SDK that has the full whitelist will be good to go, even if you roll the other packages later.

An alternative solution here is to reduce the ddc dependencies. In this case, we can provide a separate dartdevc entrypoint that we use while building the SDK. Since we only have the dependency on bazel_worker to make the integration with webdev smoother, it won't really a necessary dependency of the compiler for the local build. If we add a second entrypoint that doesn't have this dependency and use it in the build steps, we'd also elide this issue. For instance, something among these lines: https://dart-review.googlesource.com/c/sdk/+/150860

[athomas]

I have https://dart-review.googlesource.com/c/sdk/+/150931 in the CQ to update the checked-in SDKs.