Coverage provides coverage data collection, manipulation, and formatting for Dart.
collect_coverage collects coverage JSON from the Dart VM Service.
format_coverage formats JSON coverage data into either
LCOV or pretty-printed format.
dart pub global activate coverage
Consider adding the dart pub global run executables directory to your path.
See
Running a script from your PATH
for more details.
For the common use case where you just want to run all your tests, and generate an lcov.info file, you can use the test_with_coverage script:
dart pub global run coverage:test_with_coverage
By default, this script assumes it's being run from the root directory of a package, and outputs a coverage.json and lcov.info file to ./coverage/
This script is essentially the same as running:
dart run --pause-isolates-on-exit --disable-service-auth-codes --enable-vm-service=8181 test &
dart pub global run coverage:collect_coverage --wait-paused --uri=http://127.0.0.1:8181/ -o coverage/coverage.json --resume-isolates --scope-output=foo
dart pub global run coverage:format_coverage --packages=.dart_tool/package_config.json --lcov -i coverage/coverage.json -o coverage/lcov.info
For more complicated use cases, where you want to control each of these stages, see the sections below.
dart --pause-isolates-on-exit --disable-service-auth-codes --enable-vm-service=NNNN script.dart
dart pub global run coverage:collect_coverage --uri=http://... -o coverage.json --resume-isolates
or if the dart pub global run executables are on your PATH,
collect_coverage --uri=http://... -o coverage.json --resume-isolates
where --uri specifies the Dart VM Service URI emitted by the VM.
If collect_coverage is invoked before the script from which coverage is to be
collected, it will wait until it detects a VM observatory to which it can
connect. An optional --connect-timeout may be specified (in seconds). The
--wait-paused flag may be enabled, causing collect_coverage to wait until
all isolates are paused before collecting coverage.
dart pub global run coverage:format_coverage --package=app_package -i coverage.json
or if the dart pub global run exectuables are on your PATH,
format_coverage --package=app_package -i coverage.json
where app_package is the path to the package whose coverage is being collected
(defaults to the current working directory). If --sdk-root is set, Dart SDK
coverage will also be output.
// coverage:ignore-lineto ignore one line.// coverage:ignore-startand// coverage:ignore-endto ignore range of lines inclusive.// coverage:ignore-fileto ignore the whole file.
Then pass --check-ignore to format_coverage.
To gather function level coverage information, pass --function-coverage to
collect_coverage:
dart --pause-isolates-on-exit --disable-service-auth-codes --enable-vm-service=NNNN script.dart
dart pub global run coverage:collect_coverage --uri=http://... -o coverage.json --resume-isolates --function-coverage
To gather branch level coverage information, pass --branch-coverage to both
collect_coverage and the Dart command you're gathering coverage from:
dart --pause-isolates-on-exit --disable-service-auth-codes --enable-vm-service=NNNN --branch-coverage script.dart
dart pub global run coverage:collect_coverage --uri=http://... -o coverage.json --resume-isolates --branch-coverage
Branch coverage requires Dart VM 2.17.0, with service API v3.56. Function, branch, and line coverage can all be gathered at the same time, by combining those flags:
dart --pause-isolates-on-exit --disable-service-auth-codes --enable-vm-service=NNNN --branch-coverage script.dart
dart pub global run coverage:collect_coverage --uri=http://... -o coverage.json --resume-isolates --function-coverage --branch-coverage
These flags can also be passed to test_with_coverage:
pub global run coverage:test_with_coverage --branch-coverage --function-coverage