Dart artifacts are not built the same way in Fuchsia as they are on other platforms.
Instead of relying on pub
to manage dependencies, sources of third-party packages we depend on are checked into the tree under //third_party/dart-pkg
. This is to ensure we use consistent versions of our dependencies across multiple builds.
Likewise, no build output is placed in the source tree as everything goes under out/
. That includes .packages
files which are generated as part of the build based on a target's dependency.
The Dart runner for Fuchsia does not monitor the FIDL channels opened by Dart programs and as a result does not end the program normally, but rather waits for the explicit call to fuchsia.exit()
to indicate the program should be ended.
Note: Calling exit() from dart:io will result in an exception since components are not allowed to call this method since it would shutdown the dart_runner process.
import 'package:fuchsia/fuchsia.dart' as fuchsia; void main(List<String> args) { print('Hello Dart!'); fuchsia.exit(23); }
There are five gn targets for building Dart:
dart_library
defines a library that can be used by other Dart targets;dart_app
defines a Dart executable for Fuchsia;dart_tool
defines a Dart tool for the host;flutter_app
defines a Flutter application;dart_test
defines a group of test.See the definitions of each of these targets for how to use them.
We use a layout very similar to the standard layout.
my_package/ | |-- pubspec.yaml # Empty, used as a marker [mandatory] |-- BUILD.gn # Contains all targets |-- analysis_options.yaml # Analysis configuration [mandatory] |-- lib/ # dart_library contents |-- bin/ # dart_binary's (target) or dart_tool's (host) |-- test/ # dart_test contents