Fine. Make ManifestItemId use a monotonic 64-bit counter Replace `(timestamp, randomBits)` with a lexicographically ordered `(hi32, lo32)` pair to generate IDs from a monotonic counter rather than wall time. `lo32` is a 32-bit counter seeded from the current time and incremented modulo 2^32; `hi32` increments only when `lo32` wraps. This removes dependence on low-resolution timers (notably on Windows) that could produce non-monotonic ordering when many IDs were generated in the same tick. Within a process, IDs are now strictly increasing. Notable changes: * Update `generate()` to bump `lo32` and carry into `hi32` on wrap. * Rename fields to `hi32`/`lo32`; update equality, hash, and compare. * Keep serialization as two `UInt32`s, now writing `hi32` then `lo32`. (This alters on-disk semantics; existing caches may need invalidation.) * Simplify `toString()` to print the `(hi32, lo32)` tuple. This change improves determinism and ordering guarantees without relying on platform timer resolution. Cross-run ordering is no longer tied to wall time and may differ from prior behavior. Change-Id: Ib3b1196ca3f6714a90dd2f1847e6e8b9a7bad957 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/446701 Reviewed-by: Johnni Winther <johnniwinther@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com> https://dart.googlesource.com/sdk/+/2aea88f002cfe1390fd1db69942e406a2e79f217
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.