coverage fails to generate coverage.lcov

Question

I'm having trouble generating coverage.lcov
running github action in a monorepo (using melos)
I think the problem may be caused by coverage, but it's also possible
that I have missed some breaking change (the past year I was busy)

this is the relevant part of melos.yaml

  test:format:
    run: melos exec -c 1 -- format_coverage --lcov --check-ignore  --in=coverage --out=coverage.lcov --packages=.packages --report-on=lib
    description: Format Dart tests' coverage data
    select-package:
      flutter: false
      dir-exists: test

and this is the coverage command that fails

format_coverage --lcov --check-ignore  --in=coverage --out=coverage.lcov --packages=.packages --report-on=lib

with these logs

261
Unhandled exception:
262
FormatException: Unexpected character (at character 1)
263
# This file is deprecated. Tools should instead consume 
264
^
265
#0      throwError (package:package_config/src/errors.dart:32:35)
266
#1      parsePackageConfigString (package:package_config/src/package_config_json.dart:54:12)
267
#2      PackageConfig.parseString (package:package_config/src/package_config.dart:94:7)
268
#3      Resolver._parsePackages (package:coverage/src/resolver.dart:115:23)
269
#4      Resolver.create (package:coverage/src/resolver.dart:34:13)
270
#5      HitMap.parseJson (package:coverage/src/hitmap.dart:191:46)
271
#6      HitMap.parseFiles (package:coverage/src/hitmap.dart:212:41)
272
#7      main (file:///home/runner/.pub-cache/hosted/pub.dartlang.org/coverage-1.5.0/bin/format_coverage.dart:66:31)
273
#8      _delayEntrypointInvocation.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:295:32)
274
#9      _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:192:12)
279
--------------------------------------------------------------------------------

what is the correct command to generate coverage.lcov?

here are the logs

score 0 · Answer 1 · answered Jul 06 '22 at 16:00

0

Please, try this

dart pub global run coverage:format_coverage --packages=.dart_tool/package_config.json --report-on=lib --lcov -i coverage -o coverage/lcov.info

See details here.

answered Jul 06 '22 at 16:00

darkstarx

1
1

this didn't help much in my case, being a monorepo and with the use of melos this code doesn't really fit the ci script – Francesco Iapicca Jul 18 '22 at 11:17

score 0 · Accepted Answer · answered Jul 18 '22 at 11:24

it turned out the commands
dart test --coverage="coverage"
and
flutter test --coverage
already output a lcov.info file
(I'm quite sure that wasn't always the case)
so no need to run format_coverage at all

(and codecov/codecov-action@v3 picks that up nicely)

coverage fails to generate coverage.lcov

2 Answers2