add a option to disable the plugin (#25)

This is especially useful when debugging potential incompatibilites with the vanilla collection

pytest_pytorch/plugin.py

@@ -13,7 +13,7 @@
     TORCH_AVAILABLE = False
 
     warnings.warn(
-        "Disabling the plugin 'pytest-pytorch', because 'torch' could not be imported."
+        "Disabling the `pytest-pytorch` plugin, because 'torch' could not be imported."
     )
 
 
@@ -87,10 +87,22 @@ def collect(self):
             yield from super().collect()
 
 
+def pytest_addoption(parser, pluginmanager):
+    parser.addoption(
+        "--disable-pytest-pytorch",
+        action="store_true",
+        help="Disable the `pytest-pytorch` plugin",
+    )
+    return None
+
+
 def pytest_pycollect_makeitem(collector, name, obj):
     if not TORCH_AVAILABLE:
         return None
 
+    if collector.config.getoption("disable_pytest_pytorch"):
+        return None
+
     try:
         if not issubclass(obj, TestCaseTemplate) or obj is TestCaseTemplate:
             return None

tests/assets/test_disabled.py

@@ -0,0 +1,15 @@
+from torch.testing._internal.common_device_type import instantiate_device_type_tests
+from torch.testing._internal.common_utils import TestCase
+
+
+class TestFoo(TestCase):
+    def test_bar(self, device):
+        pass
+
+
+instantiate_device_type_tests(TestFoo, globals(), only_for="cpu")
+
+
+class TestSpam(TestCase):
+    def test_ham(self):
+        pass

tests/conftest.py

@@ -8,6 +8,10 @@ def collect_tests(testdir):
     def collect_tests_(file: str, cmds: str):
         testdir.copy_example(file)
         result = testdir.runpytest("--quiet", "--collect-only", *cmds)
+
+        if result.outlines[-1].startswith("no tests collected"):
+            return set()
+
         assert result.ret == pytest.ExitCode.OK
 
         collection = set()

tests/test_cli.py

@@ -0,0 +1,7 @@
+import pytest
+
+
+@pytest.mark.parametrize("option", ["--disable-pytest-pytorch"])
+def test_disable_pytest_pytorch(testdir, option):
+    result = testdir.runpytest("--help")
+    assert option in "\n".join(result.outlines)

tests/test_plugin.py

@@ -179,3 +179,45 @@ def test_op_infos(collect_tests, file, cmds, selection):
 def test_nested_names(collect_tests, file, cmds, selection):
     collection = collect_tests(file, cmds)
     assert collection == selection
+
+
+@make_parametrization(
+    Config(
+        selection=(
+            "::TestFooCPU::test_bar_cpu",
+            "::TestSpam::test_ham",
+        ),
+    ),
+    Config(
+        new_cmds="::TestFoo",
+        selection=(),
+    ),
+    Config(
+        new_cmds="::TestFoo::test_bar",
+        selection=(),
+    ),
+    Config(
+        new_cmds="::TestFooCPU",
+        legacy_cmds=("-k", "TestFoo"),
+        selection=("::TestFooCPU::test_bar_cpu",),
+    ),
+    Config(
+        new_cmds="::TestFooCPU::test_bar_cpu",
+        legacy_cmds=("-k", "TestFoo and test_bar"),
+        selection=("::TestFooCPU::test_bar_cpu",),
+    ),
+    Config(
+        new_cmds="::TestSpam",
+        legacy_cmds=("-k", "TestSpam"),
+        selection=("::TestSpam::test_ham",),
+    ),
+    Config(
+        new_cmds="::TestSpam::test_ham",
+        legacy_cmds=("-k", "TestSpam and test_ham"),
+        selection=("::TestSpam::test_ham",),
+    ),
+    file="test_disabled.py",
+)
+def test_disabled(collect_tests, file, cmds, selection):
+    collection = collect_tests(file, ("--disable-pytest-pytorch", *cmds))
+    assert collection == selection