`bazel coverage` is not showing the number of functions hit/coverage

[wsoesanto-arbo]

🐞 bug report

Affected Rule

The issue is caused by the rule: py_test.

Is this a regression?

Not sure.

Description

I have the following python library file.

def sum(a: int, b: int) -> int:
    if a == 0:
        return b
    return a + b


def uncalled_function():
    pass

The test file is the following:

import unittest
from pytestcoverage.example import sum


class ExampleTest(unittest.TestCase):

    def test_example(self):
        self.assertEqual(sum(1, 2), 3)

    def test_example2(self):
        self.assertEqual(sum(0, 2), 2)


if __name__ == "__main__":
    unittest.main()

I ran bazel coverage //pytestcoverage:example_test and it produces the following .dat file.

SF:pytestcoverage/example.py
FNF:0
FNH:0
BRDA:3,0,0,1
BRDA:4,0,1,1
BRF:2
BRH:2
DA:1,1,TEm0m03zdmZoLvEEYvcd3g
DA:2,1,qz5GR5TDab0xK5yEyEXvVA
DA:3,1,iX7Q3CYbMsKz6tK3+NbOAQ
DA:4,1,Ro176RhJvDYGuBP1DF9bzA
DA:7,1,QO5oDInC/FETpNCZmYWtnA
DA:8,0,PdeqDqr4bOft68ON3+/7kg
LH:5
LF:6
end_of_record

It seems it's able to know which line is covered. Unfortunately it couldn't tell the number of functions that are covered. Hence 0 value on FNF and FNH. This can also be seen from genhtml lcov program.

🔬 Minimal Reproduction

https://github.com/wsoesanto-arbo/pytestcoverage

🔥 Exception or Error

No error

🌍 Your Environment

Operating System:

  
Linux sg-dev-willy 6.8.0-52-generic #53~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Jan 15 19:18:46 UTC 2 x86_64 x86_64 x86_64 GNU/Linux
  

Output of bazel version:

  
7.5.0
  

Rules_python version:

  
http_archive(
    name = "rules_python",
    sha256 = "2ef40fdcd797e07f0b6abda446d1d84e2d9570d234fddf8fcd2aa262da852d1c",
    strip_prefix = "rules_python-1.2.0",
    url = "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/bazelbuild/rules_python/releases/download/1.2.0/rules_python-1.2.0.tar.gz",
)
  

Anything else relevant?

I think I have provided the most basic information on the setup. Let me know if you need more information on it. Thanks!

[aignas]

Bazel 7.5 has a bug related to coverage, please test 7.6 or the latest 8 release.

[wsoesanto-arbo]

Hi @aignas thanks for the reply. I have just tried 7.6.0 and 8.1.1 (which is the latest at the current time of writing) and it still doesn't work

[aignas]

What commands are you running to get the coverage? I cannot find this information anywhere.

[wsoesanto-arbo]

bazel coverage //pytestcoverage:example_test on the repo https://github.com/wsoesanto-arbo/pytestcoverage

[aignas]

Is it the same if you add --combined_report as per original docs? https://bazel.build/configure/coverage#running_coverage

[wsoesanto-arbo]

Unfortunately yes

[aignas]

I wonder if #2607 affected this. I am not sure when I'll have to look into this, so marking as help wanted.

[aignas]

I looked at the https://github.com/wsoesanto-arbo/pytestcoverage/blob/main/.bazelrc, but it is a bit long, so here's my best attempt to extract the relevant bits:

common --enable_bzlmod=0
build --incompatible_default_to_explicit_init_py
build --java_runtime_version=remotejdk_11
build --@rules_python//python/config_settings:bootstrap_impl=script

[aignas]

I tried running this on my machine (Linux x86_64):

$ cat bazel-out/_coverage/_coverage_report.dat
SF:pytestcoverage/example.py
FNF:0
FNH:0
BRDA:3,0,0,1
BRDA:4,0,1,1
BRF:2
BRH:2
DA:1,1,TEm0m03zdmZoLvEEYvcd3g
DA:2,1,qz5GR5TDab0xK5yEyEXvVA
DA:3,1,iX7Q3CYbMsKz6tK3+NbOAQ
DA:4,1,Ro176RhJvDYGuBP1DF9bzA
DA:7,1,QO5oDInC/FETpNCZmYWtnA
DA:8,0,PdeqDqr4bOft68ON3+/7kg
LH:5
LF:6

And then generated the html output and got:

Directory Sort by file name	Line Coverage Sort by line coverage	Branch Coverage Sort by branch coverage
Rate	Total	Hit	Rate	Total	Hit
[pytestcoverage/](https://github.com/bazel-contrib/rules_python/issues/pytestcoverage/index.html)	
83.3%83.3%
83.3 %	6	5	100.0 %	2	2
Note: 'Function Coverage' columns elided as function owner is not identified.

This was with:

bazel coverage //pytestcoverage:example_test
genhtml --branch-coverage --output genhtml "$(bazel info output_path)/_coverage/_coverage_report.dat"

So I'll close this as "Cannot reproduce".