fix: generate xml report packages correctly on windows

[bparzella]

This will fix the problem of duplicate package elements with the same name in the xml report generated on windows.

Closes #1573

[bparzella]

If the for loop is run, the rel_name is generated from filename which is already converted from backslash to slash in line 177

When the else branch is run, rel_name is generated from the FileReporter which needs the conversion

[blakeNaccarato]

Coming here from the Coverage.py Mastodon request for someone on a Windows machine to validate this. I cloned this repo and checked out the PR. I installed it in a virtual environment on Python 3.11 with pip install . and ran pytest. It works fine, with the result 1299 passed, 28 skipped in 70.21s (0:01:10).

@nedbat Is there any log file I should share that would help satisfy the request to validate the fix? Or are you looking for it to be tested in an actual use-case scenario, rather than in the test suite?

Also, click to expand the details below on issues I had even getting the dev installation to work on my Windows machine, which is why I fell back to good old pip install .. Neither installing requirements/dev.pip nor running tox worked on my machine, due to pywin32-ctypes>=0.2.0 not being == pinned. A separate issue entirely, but I just thought I'd point it out.

Notes on dev install not working...

I followed the setup instructions

py -3.11 -m venv .venv
.\.venv\Scripts\activate
pip install -r requirements/dev.pip

But I got an error from pip install -r requirements/dev.pip about pywin32-ctypes>=0.2.0 not being == pinned.

ERROR: In --require-hashes mode, all requirements must have their versions pinned with ==. These do not:
    pywin32-ctypes>=0.2.0 from https://files.pythonhosted.org/packages/9e/4b/3ab2720f1fa4b4bc924ef1932b842edf10007e4547ea8157b0b9fc78599a/pywin32_ctypes-0.2.0-py2.py3-none-any.whl (from keyring==23.13.1->-r requirements/dev.pip 
(line 292))

So I ran pip install -r requirements/dev.pip instead, but got essentially the same error after running tox

ERROR: In --require-hashes mode, all requirements must have their versions pinned with ==. These do not:
    pywin32-ctypes>=0.2.0 from https://files.pythonhosted.org/packages/9e/4b/3ab2720f1fa4b4bc924ef1932b842edf10007e4547ea8157b0b9fc78599a/pywin32_ctypes-0.2.0-py2.py3-none-any.whl (from keyring==23.13.1->-r requirements/lint.pip (line 330))
lint: exit 1 (35.52 seconds) C:\Users\<...>\Code\other\coveragepy> python -m pip install -U -r requirements/lint.pip pid=12740
.pkg: _exit> python C:\Users\<...>\Code\other\coveragepy\.venv\Lib\site-packages\pyproject_api\_backend.py True setuptools.build_meta
  py37: SKIP (0.02 seconds)
  py38: SKIP (0.02 seconds)
  py39: SKIP (0.05 seconds)
  py310: SKIP (0.00 seconds)
  py311: OK (203.17=setup[63.98]+cmd[0.61,4.41,14.73,70.73,0.39,48.31] seconds)
  py312: SKIP (0.02 seconds)
  pypy3: SKIP (0.00 seconds)
  doc: FAIL code 2 (58.92=setup[45.66]+cmd[0.48,12.78,0.00] seconds)
  lint: FAIL code 1 (36.34 seconds)
  evaluation failed :( (299.25 seconds)

So I just installed coveragepy directly into my .venv with pip install .. I also ran pip install -r requirements/pytest.pip. Upon running pytest

[nedbat]

@blakeNaccarato thanks! Did you try to reproduce the error from the original issue #1573? We have CI that confirms the pull request works, but it's hard to demonstrate the problem first.

@bparzella Maybe we could use your zip file from #1573 as the basis for a new test?

[blakeNaccarato]

I can verify on my Windows machine that <package name="namespace.package1"...> is duplicated when installing pip install coverage, but not when installing pip install git+https://github.com/bparzella/coveragepy.git@xml_duplicate_fix. See coverage_test_compare.zip where I wrote a script to run both versions in separate virtual environments and diff'ed the resulting coverage.xml. The diff shows an unequal occurrence of <package name="namespace.package1"...> between the two runs.

A more sophisticated way to test this would be to check the resulting xml for duplicate entries rather than a full diff.

.diff

diff --git a/pypi/proj/coverage.xml b/xml_duplicate_fix/proj/coverage.xml
index 5827aa2..c7f43c6 100644
--- a/pypi/proj/coverage.xml
+++ b/xml_duplicate_fix/proj/coverage.xml
@@ -1,6 +1,6 @@
...
@@ -8,32 +8,34 @@
 	<packages>
 		<package name="namespace.package1" line-rate="1" branch-rate="0" complexity="0">
 			<classes>
-				<class name="__main__.py" filename="namespace/package1/__main__.py" complexity="0" line-rate="1" branch-rate="0">
+				<class name="__init__.py" filename="namespace/package1/__init__.py" complexity="0" line-rate="1" branch-rate="0">
 					<methods/>
 					<lines>
...
 					</lines>
 				</class>
-				<class name="sample.py" filename="namespace/package1/sample.py" complexity="0" line-rate="1" branch-rate="0">
+				<class name="__main__.py" filename="namespace/package1/__main__.py" complexity="0" line-rate="1" branch-rate="0">
 					<methods/>
 					<lines>
...
 					</lines>
 				</class>
-				<class name="test.py" filename="namespace/package1/test.py" complexity="0" line-rate="1" branch-rate="0">
+				<class name="sample.py" filename="namespace/package1/sample.py" complexity="0" line-rate="1" branch-rate="0">
 					<methods/>
 					<lines>
...
 					</lines>
 				</class>
-			</classes>
-		</package>
-		<package name="namespace.package1.subpackage" line-rate="1" branch-rate="0" complexity="0">
-			<classes>
-				<class name="test.py" filename="namespace/package1/subpackage/test.py" complexity="0" line-rate="1" branch-rate="0">
+				<class name="test.py" filename="namespace/package1/test.py" complexity="0" line-rate="1" branch-rate="0">
 					<methods/>
 					<lines>
 						<line number="1" hits="1"/>
@@ -42,19 +44,13 @@
 				</class>
 			</classes>
 		</package>
-		<package name="namespace.package1" line-rate="1" branch-rate="0" complexity="0">
+		<package name="namespace.package1.subpackage" line-rate="1" branch-rate="0" complexity="0">
 			<classes>
-				<class name="__init__.py" filename="namespace/package1/__init__.py" complexity="0" line-rate="1" branch-rate="0">
+				<class name="test.py" filename="namespace/package1/subpackage/test.py" complexity="0" line-rate="1" branch-rate="0">
 					<methods/>
 					<lines>
...
 					</lines>
 				</class>
 			</classes>

[bparzella]

@bparzella Maybe we could use your zip file from #1573 as the basis for a new test?

@nedbat That sounds like a good idea, I'll look into it.

[bparzella]

Running the test on windows using the master branch has the following results:

py310: commands[3]> python igor.py test_with_tracer c tests\test_xml.py::XmlReportTest::test_no_duplicate_packages
=== CPython 3.10.10 (rev aad5f6a) with C tracer (.tox\py310\Scripts\python.EXE) ===
bringing up nodes...
bringing up nodes...

F                                                                                                                                                                                                                                       [100%]
================================================================================================================== FAILURES ================================================================================================================== 
__________________________________________________________________________________________________ XmlReportTest.test_no_duplicate_packages __________________________________________________________________________________________________ 
[gw0] win32 -- Python 3.10.10 (...)\.tox\py310\Scripts\python.EXE

self = <tests.test_xml.XmlReportTest object at 0x000002C6ECD8A290>

    def test_no_duplicate_packages(self) -> None:
        self.make_file(
            "namespace/package/__init__.py",
            "from . import sample; from . import test; from .subpackage import test"
        )
        self.make_file("namespace/package/sample.py", "print('package.sample')")
        self.make_file("namespace/package/test.py", "print('package.test')")
        self.make_file("namespace/package/subpackage/test.py", "print('package.subpackage.test')")

        # no source path passed to coverage!
        # problem occurs when they are dynamically generated during xml report
        cov = coverage.Coverage()

        cov.start()
        import_local_file("foo", "namespace/package/__init__.py")               # pragma: nested
        cov.stop()                                                              # pragma: nested

        cov.xml_report()

        dom = ElementTree.parse("coverage.xml")

        # only two packages should be present
        packages = dom.findall(".//package")
>       assert len(packages) == 2
E       AssertionError: assert 3 == 2
E        +  where 3 = len([<Element 'package' at 0x000002C6ECD4FC40>, <Element 'package' at 0x000002C6ECEBEC00>, <Element 'package' at 0x000002C6ECEBF560>])

(...)\tests\test_xml.py:344: AssertionError
------------------------------------------------------------------------------------------------------------ Captured stdout call ------------------------------------------------------------------------------------------------------------ 
package.sample
package.test
package.subpackage.test
========================================================================================================== short test summary info =========================================================================================================== 
FAILED tests/test_xml.py::XmlReportTest::test_no_duplicate_packages - AssertionError: assert 3 == 2

[nedbat]

This is now released as part of coverage 7.2.2.