🐞 Fix handling empty coverage

[ckunki]

Currently, the GitHub workflow report.yml fails with error message

CalledProcessError: Command '['coverage', 'json', '--data-file=.coverage', '-o', '/tmp/tmpbe4nkhye/coverage.json']' returned non-zero exit status 2.
nox > Session project:report failed.

See example.

Experiments showed that the stout of the command showed

No data to report.

In consequence, the command did not create a json file and the following commands trying to open and read the json file failed.

The current ticket therefore requests to change Function total_coverage() to

• report the output of command coverage instead of hiding it
• return total coverage of 100 % in case of an empty project with no lines to be covered.

[ckunki]

def total_coverage(file: Union[str, Path]) -> float:
    with TemporaryDirectory() as tmpdir:
        tmp_dir = Path(tmpdir)
        report = tmp_dir / "coverage.json"
        p = subprocess.run(
            ["coverage", "json", f"--data-file={file}", "-o", f"{report}"],
            capture_output=True,
            check=False,
            encoding="utf-8",
        )
        stdout = p.stdout.strip()
        if (p.returncode == 1) and (stdout == "No data to report."):
            print(
                f'The following command'
                f' returned non-zero exit status {p.returncode}:\n'
                f'  {" ".join(p.args)}\n'
                f'{stdout}\n'
                'Returning total coverage 100 %.',
                file=sys.stderr,
            )
            return 100.0
        with open(report, encoding="utf-8") as r:
            data = json.load(r)
            total: float = data["totals"]["percent_covered"]

        return total

[ckunki]

Findings in report.yml, columns:

• DEVDOC: whether the resp. finding affects the repository developer-documentation,
• PTB: whether the finding affects the folder .github/workflows/ in the PTB
• PTB Template: whether the finding affects the folder exasol/toolbox/templates/github/workflows/ in the PTB

Location	Finding	DEVDOC	PTB	PTB Template
Step "Generate GitHub Summary", poetry run -- coverage report --format markdown	must ignore coverage error due to no data	Y	Y	Y
Step "Copy Artifacts into Root Folder"	copies 2x .lint.txt but must copy .lint.json, too	Y	-	Y
Step "Generate GitHub Summary"	contains 2x security, but must be 1x lint and 1x security	Y	-	-