[ddc] Library level expression evaluation for the Dart SDK. Today, support for expression evaluation in DDC uses a lot of information. To properly support compiling expressions in arbitrary frames, we consume source-maps, module metadata, and full kernel components at various stages of the process. This data is already plumbed and available for non-sdk modules in our debugging systems (frontend-server, webdev, g3), however it is not available the Dart SDK module itself. Because of that, the expression compiler today rejects all expression evaluation requests when the target is a Dart SDK library. Until the fix the availability of this data everywhere, we believe we can support a limited form of expression evaluation: only evaluation of libary level expressions. Basically, expressions where scope data is not necessary and kernel outlines are sufficient to compile the expression. Here we introduce logic to recognize the first offset location of a library, which is a clear indicator that no scope data is needed and a library level expression evaluation is being requested. This change is an attempt to help resolve https://github.com/flutter/devtools/issues/7766. Note: just like changes were needed here in the worker and test-compiler files, it is possible that some change may be necessary in dwds and other parts of the pipeline. Additional validation will be needed after this lands. Change-Id: Iff081a24ecb05092407279a0a7ed3d38c13cf41d Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367981 Reviewed-by: Nicholas Shahan <nshahan@google.com> Commit-Queue: Sigmund Cherem <sigmund@google.com> https://dart.googlesource.com/sdk/+/9dad32ce412a1d6085e783d3d55d707f8f157ef9
Monorepo is:
With depot_tools installed and on your path, create a directory for your monorepo checkout and run these commands to create a gclient solution in that directory:
mkdir monorepo cd monorepo gclient config --unmanaged https://dart.googlesource.com/monorepo gclient sync -D
This gives you a checkout in the monorepo directory that contains:
monorepo/ DEPS - the DEPS used for this gclient checkout commits.json - the pinned commits for Dart, flutter/engine, and flutter/flutter tools/ - scripts used to create monorepo DEPS engine/src/ - the flutter/buildroot repo flutter/ - the flutter/engine repo out/ - the build directory, where Flutter engine builds are created third_party/ - Flutter dependencies checked out by DEPS dart/ - the Dart SDK checkout. third_party - Dart dependencies, also used by Flutter flutter/ - the flutter/flutter repo
Flutter's instructions for building the engine are at Compiling the engine
They can be followed closely, with a few changes:
goma_ctl ensure_start is sufficient.Example build commands that work on linux:
MONOREPO_PATH=$PWD if [[ ! $PATH =~ (^|:)$MONOREPO_PATH/flutter/bin(:|$) ]]; then PATH=$MONOREPO_PATH/flutter/bin:$PATH fi export GOMA_DIR=$(dirname $(command -v gclient))/.cipd_bin goma_ctl ensure_start pushd engine/src flutter/tools/gn --goma --no-prebuilt-dart-sdk --unoptimized --full-dart-sdk autoninja -C out/host_debug_unopt popd
The Flutter commands used to build and run apps will use the locally built Flutter engine and Dart SDK, instead of the one downloaded by the Flutter tool, if the --local-engine option is provided.
For example, to build and run the Flutter spinning square sample on the web platform,
MONOREPO_PATH=$PWD cd flutter/examples/layers flutter --local-engine=host_debug_unopt \ -d chrome run widgets/spinning_square.dart cd $MONOREPO_PATH
To build for desktop, specify the desktop platform device in flutter run as -d macos or -d linux or -d windows. You may also need to run the command
flutter create --platforms=windows,macos,linux
on existing apps, such as sample apps. New apps created with flutter create already include these support files. Details of desktop support are at Desktop Support for Flutter
Tests in the Flutter source tree can be run with the flutter test command, run in the directory of a package containing tests. For example:
MONOREPO_PATH=$PWD cd flutter/packages/flutter flutter test --local-engine=host_debug_unopt cd $MONOREPO_PATH
Please file an issue or email the dart-engprod team with any problems with or questions about using monorepo.
We will update this documentation to address them.
flutter commands may download the engine and Dart SDK files for the configured channel, even though they will be using the local engine and its SDK.gclient sync needs to be run in an administrator session, because some installed dependencies create symlinks.