Silence spurious warnings when xdist is used

.travis.yml

@@ -23,91 +23,59 @@ jobs:
     - stage: tests
       env: TOXENV=py27-pytest46-xdist27-coverage45
       python: '2.7'
-    - env: TOXENV=py27-pytest46-xdist27-coverage50
+    - env: TOXENV=py27-pytest46-xdist27-coverage51
       python: '2.7'
     - env: TOXENV=py35-pytest46-xdist27-coverage45
       python: '3.5'
-    - env: TOXENV=py35-pytest46-xdist27-coverage50
+    - env: TOXENV=py35-pytest46-xdist27-coverage51
       python: '3.5'
     - env: TOXENV=py36-pytest46-xdist27-coverage45
       python: '3.6'
-    - env: TOXENV=py36-pytest46-xdist27-coverage50
+    - env: TOXENV=py36-pytest46-xdist27-coverage51
       python: '3.6'
     - env: TOXENV=py37-pytest46-xdist27-coverage45
       python: '3.7'
-    - env: TOXENV=py37-pytest46-xdist27-coverage50
+    - env: TOXENV=py37-pytest46-xdist27-coverage51
       python: '3.7'
     - env: TOXENV=pypy-pytest46-xdist27-coverage45
       python: 'pypy'
-    - env: TOXENV=pypy-pytest46-xdist27-coverage50
+    - env: TOXENV=pypy-pytest46-xdist27-coverage51
       python: 'pypy'
     - env: TOXENV=pypy3-pytest46-xdist27-coverage45
       python: 'pypy3'
-    - env: TOXENV=pypy3-pytest46-xdist27-coverage50
+    - env: TOXENV=pypy3-pytest46-xdist27-coverage51
       python: 'pypy3'
-    - env: TOXENV=py36-pytest46-xdist29-coverage45
+    - env: TOXENV=py36-pytest46-xdist32-coverage45
       python: '3.6'
-    - env: TOXENV=py36-pytest46-xdist29-coverage50
+    - env: TOXENV=py36-pytest46-xdist32-coverage51
       python: '3.6'
-    - env: TOXENV=py36-pytest46-xdist31-coverage45
+    - env: TOXENV=py36-pytest54-xdist32-coverage45
       python: '3.6'
-    - env: TOXENV=py36-pytest46-xdist31-coverage50
+    - env: TOXENV=py36-pytest54-xdist32-coverage51
       python: '3.6'
-    - env: TOXENV=py36-pytest53-xdist29-coverage45
-      python: '3.6'
-    - env: TOXENV=py36-pytest53-xdist29-coverage50
-      python: '3.6'
-    - env: TOXENV=py36-pytest53-xdist31-coverage45
-      python: '3.6'
-    - env: TOXENV=py36-pytest53-xdist31-coverage50
-      python: '3.6'
-    - env: TOXENV=py37-pytest46-xdist29-coverage45
-      python: '3.7'
-    - env: TOXENV=py37-pytest46-xdist29-coverage50
-      python: '3.7'
-    - env: TOXENV=py37-pytest46-xdist31-coverage45
-      python: '3.7'
-    - env: TOXENV=py37-pytest46-xdist31-coverage50
-      python: '3.7'
-    - env: TOXENV=py37-pytest53-xdist29-coverage45
+    - env: TOXENV=py37-pytest46-xdist32-coverage45
       python: '3.7'
-    - env: TOXENV=py37-pytest53-xdist29-coverage50
+    - env: TOXENV=py37-pytest46-xdist32-coverage51
       python: '3.7'
-    - env: TOXENV=py37-pytest53-xdist31-coverage45
+    - env: TOXENV=py37-pytest54-xdist32-coverage45
       python: '3.7'
-    - env: TOXENV=py37-pytest53-xdist31-coverage50
+    - env: TOXENV=py37-pytest54-xdist32-coverage51
       python: '3.7'
-    - env: TOXENV=py38-pytest46-xdist29-coverage45
+    - env: TOXENV=py38-pytest46-xdist32-coverage45
       python: '3.8'
-    - env: TOXENV=py38-pytest46-xdist29-coverage50
+    - env: TOXENV=py38-pytest46-xdist32-coverage51
       python: '3.8'
-    - env: TOXENV=py38-pytest46-xdist31-coverage45
+    - env: TOXENV=py38-pytest54-xdist32-coverage45
       python: '3.8'
-    - env: TOXENV=py38-pytest46-xdist31-coverage50
+    - env: TOXENV=py38-pytest54-xdist32-coverage51
       python: '3.8'
-    - env: TOXENV=py38-pytest53-xdist29-coverage45
-      python: '3.8'
-    - env: TOXENV=py38-pytest53-xdist29-coverage50
-      python: '3.8'
-    - env: TOXENV=py38-pytest53-xdist31-coverage45
-      python: '3.8'
-    - env: TOXENV=py38-pytest53-xdist31-coverage50
-      python: '3.8'
-    - env: TOXENV=pypy3-pytest46-xdist29-coverage45
-      python: 'pypy3'
-    - env: TOXENV=pypy3-pytest46-xdist29-coverage50
-      python: 'pypy3'
-    - env: TOXENV=pypy3-pytest46-xdist31-coverage45
-      python: 'pypy3'
-    - env: TOXENV=pypy3-pytest46-xdist31-coverage50
-      python: 'pypy3'
-    - env: TOXENV=pypy3-pytest53-xdist29-coverage45
+    - env: TOXENV=pypy3-pytest46-xdist32-coverage45
       python: 'pypy3'
-    - env: TOXENV=pypy3-pytest53-xdist29-coverage50
+    - env: TOXENV=pypy3-pytest46-xdist32-coverage51
       python: 'pypy3'
-    - env: TOXENV=pypy3-pytest53-xdist31-coverage45
+    - env: TOXENV=pypy3-pytest54-xdist32-coverage45
       python: 'pypy3'
-    - env: TOXENV=pypy3-pytest53-xdist31-coverage50
+    - env: TOXENV=pypy3-pytest54-xdist32-coverage51
       python: 'pypy3'
 
     - stage: examples

appveyor.yml

@@ -4,11 +4,11 @@ build: off
 environment:
   matrix:
     - TOXENV: check
-    - TOXENV: 'py27-pytest46-xdist27-coverage45,py27-pytest46-xdist27-coverage50'
-    - TOXENV: 'py35-pytest46-xdist27-coverage45,py35-pytest46-xdist27-coverage50'
-    - TOXENV: 'py36-pytest46-xdist27-coverage45,py36-pytest46-xdist27-coverage50,py36-pytest46-xdist29-coverage45,py36-pytest46-xdist29-coverage50,py36-pytest46-xdist31-coverage45,py36-pytest46-xdist31-coverage50,py36-pytest53-xdist29-coverage45,py36-pytest53-xdist29-coverage50,py36-pytest53-xdist31-coverage45,py36-pytest53-xdist31-coverage50'
-    - TOXENV: 'py37-pytest46-xdist27-coverage45,py37-pytest46-xdist27-coverage50,py37-pytest46-xdist29-coverage45,py37-pytest46-xdist29-coverage50,py37-pytest46-xdist31-coverage45,py37-pytest46-xdist31-coverage50,py37-pytest53-xdist29-coverage45,py37-pytest53-xdist29-coverage50,py37-pytest53-xdist31-coverage45,py37-pytest53-xdist31-coverage50'
-    - TOXENV: 'pypy-pytest46-xdist27-coverage45,pypy-pytest46-xdist27-coverage50'
+    - TOXENV: 'py27-pytest46-xdist27-coverage45,py27-pytest46-xdist27-coverage51'
+    - TOXENV: 'py35-pytest46-xdist27-coverage45,py35-pytest46-xdist27-coverage51'
+    - TOXENV: 'py36-pytest46-xdist27-coverage45,py36-pytest46-xdist27-coverage51,py36-pytest46-xdist32-coverage45,py36-pytest46-xdist32-coverage51,py36-pytest54-xdist32-coverage45,py36-pytest54-xdist32-coverage51'
+    - TOXENV: 'py37-pytest46-xdist27-coverage45,py37-pytest46-xdist27-coverage51,py37-pytest46-xdist32-coverage45,py37-pytest46-xdist32-coverage51,py37-pytest54-xdist32-coverage45,py37-pytest54-xdist32-coverage51'
+    - TOXENV: 'pypy-pytest46-xdist27-coverage45,pypy-pytest46-xdist27-coverage51'
 
 init:
   - ps: echo $env:TOXENV

src/pytest_cov/engine.py

@@ -218,7 +218,11 @@ def start(self):
 
         self.cov = coverage.Coverage(source=self.cov_source,
                                      branch=self.cov_branch,
+                                     data_suffix=True,
                                      config_file=self.cov_config)
+        self.cov._warn_no_data = False
+        self.cov._warn_unimported_source = False
+        self.cov._warn_preimported_source = False
         self.combining_cov = coverage.Coverage(source=self.cov_source,
                                                branch=self.cov_branch,
                                                data_file=os.path.abspath(self.cov.config.data_file),

tests/test_pytest_cov.py

@@ -1813,6 +1813,24 @@ def test_external_data_file_xdist(testdir):
     assert glob.glob(str(testdir.tmpdir.join('some/special/place/coverage-data*')))
 
 
+def test_xdist_no_data_collected(testdir):
+    testdir.makepyfile(target="x = 123")
+    script = testdir.makepyfile("""
+import target
+def test_foobar():
+    assert target.x == 123
+""")
+    result = testdir.runpytest('-v',
+                               '--cov=target',
+                               '-n', '1',
+                               script)
+    assert result.ret == 0
+    assert 'no-data-collected' not in result.stderr.str()
+    assert 'no-data-collected' not in result.stdout.str()
+    assert 'module-not-imported' not in result.stderr.str()
+    assert 'module-not-imported' not in result.stdout.str()
+
+
 def test_external_data_file_negative(testdir):
     script = testdir.makepyfile(SCRIPT)
     testdir.tmpdir.join('.coveragerc').write("")
@@ -1869,6 +1887,29 @@ def test_do_not_append_coverage(testdir, opts, prop):
     ])
 
 
+@pytest.mark.skipif('sys.platform == "win32" and platform.python_implementation() == "PyPy"')
+def test_append_coverage_subprocess(testdir):
+    scripts = testdir.makepyfile(parent_script=SCRIPT_PARENT,
+                                 child_script=SCRIPT_CHILD)
+    parent_script = scripts.dirpath().join('parent_script.py')
+
+    result = testdir.runpytest('-v',
+                               '--cov=%s' % scripts.dirpath(),
+                               '--cov-append',
+                               '--cov-report=term-missing',
+                               '--dist=load',
+                               '--tx=2*popen',
+                               max_worker_restart_0,
+                               parent_script)
+
+    result.stdout.fnmatch_lines([
+        '*- coverage: platform *, python * -*',
+        'child_script* %s*' % CHILD_SCRIPT_RESULT,
+        'parent_script* %s*' % PARENT_SCRIPT_RESULT,
+    ])
+    assert result.ret == 0
+
+
 def test_pth_failure(monkeypatch):
     with open('src/pytest-cov.pth') as fh:
         payload = fh.read()

tox.ini

@@ -3,8 +3,8 @@
 [tox]
 envlist =
     check
-    py{27,35,36,37,py,py3}-pytest46-xdist27-coverage{45,50}
-    py{36,37,38,py3}-pytest{46,53}-xdist{29,31}-coverage{45,50}
+    py{27,35,36,37,py,py3}-pytest46-xdist27-coverage{45,51}
+    py{36,37,38,py3}-pytest{46,54}-xdist32-coverage{45,51}
     docs
 
 [testenv]
@@ -15,13 +15,16 @@ setenv =
     # Use env vars for (optional) pinning of deps.
     pytest46:  _DEP_PYTEST=pytest==4.6.9
     pytest53:  _DEP_PYTEST=pytest==5.3.2
+    pytest54:  _DEP_PYTEST=pytest==5.4.2
 
     xdist27: _DEP_PYTESTXDIST=pytest-xdist==1.27.0
     xdist29: _DEP_PYTESTXDIST=pytest-xdist==1.29.0
     xdist31: _DEP_PYTESTXDIST=pytest-xdist==1.31.0
+    xdist32: _DEP_PYTESTXDIST=pytest-xdist==1.32.0
 
     coverage45: _DEP_COVERAGE=coverage==4.5.4
-    coverage50: _DEP_COVERAGE=coverage==5.0.3
+    coverage50: _DEP_COVERAGE=coverage==5.0.4
+    coverage51: _DEP_COVERAGE=coverage==5.1
     # For testing against a coverage.py working tree.
     coveragedev: _DEP_COVERAGE=-e{env:COVERAGE_HOME}
 passenv =