From 30a7a68e3596f730af42c28e00099db5528bb4e7 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Mon, 24 Feb 2020 02:56:50 +0100
Subject: [PATCH 01/10] Remove dynamic setup of `pytest.collect` fake module

Make it a real module instead.

This was initially added in 9b58d6eaca
(https://github.com/pytest-dev/pytest/pull/2315), when removing support
for `pytest_namespace`.

Not sure if it ever worked "properly", but currently
`import pytest.collect` and `from pytest.collect import File` do not
work (but with this patch).

This is only relevant for (backward) compatibility, but the more it
appears to make sense to move it into a lazily loaded, separate file.
---
 src/_pytest/compat.py  | 24 ------------------------
 src/pytest/__init__.py |  5 -----
 src/pytest/collect.py  | 10 ++++++++++
 3 files changed, 10 insertions(+), 29 deletions(-)
 create mode 100644 src/pytest/collect.py

diff --git a/src/_pytest/compat.py b/src/_pytest/compat.py
index 1845d9d91ef..8aff8d57da4 100644
--- a/src/_pytest/compat.py
+++ b/src/_pytest/compat.py
@@ -336,30 +336,6 @@ def safe_isclass(obj: object) -> bool:
         return False
 
 
-COLLECT_FAKEMODULE_ATTRIBUTES = (
-    "Collector",
-    "Module",
-    "Function",
-    "Instance",
-    "Session",
-    "Item",
-    "Class",
-    "File",
-    "_fillfuncargs",
-)
-
-
-def _setup_collect_fakemodule() -> None:
-    from types import ModuleType
-    import pytest
-
-    # Types ignored because the module is created dynamically.
-    pytest.collect = ModuleType("pytest.collect")  # type: ignore
-    pytest.collect.__all__ = []  # type: ignore  # used for setns
-    for attr_name in COLLECT_FAKEMODULE_ATTRIBUTES:
-        setattr(pytest.collect, attr_name, getattr(pytest, attr_name))  # type: ignore
-
-
 class CaptureIO(io.TextIOWrapper):
     def __init__(self) -> None:
         super().__init__(io.BytesIO(), encoding="UTF-8", newline="", write_through=True)
diff --git a/src/pytest/__init__.py b/src/pytest/__init__.py
index 33bc3d0fbe5..1aea7c4c0e7 100644
--- a/src/pytest/__init__.py
+++ b/src/pytest/__init__.py
@@ -4,7 +4,6 @@
 """
 from _pytest import __version__
 from _pytest.assertion import register_assert_rewrite
-from _pytest.compat import _setup_collect_fakemodule
 from _pytest.config import cmdline
 from _pytest.config import ExitCode
 from _pytest.config import hookimpl
@@ -93,7 +92,3 @@
     "xfail",
     "yield_fixture",
 ]
-
-
-_setup_collect_fakemodule()
-del _setup_collect_fakemodule
diff --git a/src/pytest/collect.py b/src/pytest/collect.py
new file mode 100644
index 00000000000..fce42de5a8e
--- /dev/null
+++ b/src/pytest/collect.py
@@ -0,0 +1,10 @@
+"""Fake module for backward compatibility."""
+from . import _fillfuncargs  # noqa: F401
+from . import Class  # noqa: F401
+from . import Collector  # noqa: F401
+from . import File  # noqa: F401
+from . import Function  # noqa: F401
+from . import Instance  # noqa: F401
+from . import Item  # noqa: F401
+from . import Module  # noqa: F401
+from . import Session  # noqa: F401

From 9815b6953d7964569329fc1c22fe805afbb30651 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Mon, 24 Feb 2020 04:20:44 +0100
Subject: [PATCH 02/10] test

---
 testing/test_meta.py | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/testing/test_meta.py b/testing/test_meta.py
index ffc8fd38aba..e081e2fd56b 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -13,11 +13,17 @@
 
 
 def _modules():
-    return sorted(
-        n
-        for _, n, _ in pkgutil.walk_packages(
-            _pytest.__path__, prefix=_pytest.__name__ + "."
+    extra = [
+        "pytest.collect",
+    ]
+    return (
+        sorted(
+            n
+            for _, n, _ in pkgutil.walk_packages(
+                _pytest.__path__, prefix=_pytest.__name__ + "."
+            )
         )
+        + extra
     )
 
 

From 8a8b1f67a8b14d892f0ba42f01df5a01bb8923f9 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Wed, 26 Feb 2020 15:44:50 +0100
Subject: [PATCH 03/10] eager import

---
 src/pytest/__init__.py | 2 ++
 testing/test_meta.py   | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/src/pytest/__init__.py b/src/pytest/__init__.py
index 1aea7c4c0e7..dab6f543675 100644
--- a/src/pytest/__init__.py
+++ b/src/pytest/__init__.py
@@ -44,6 +44,7 @@
 from _pytest.warning_types import PytestUnhandledCoroutineWarning
 from _pytest.warning_types import PytestUnknownMarkWarning
 from _pytest.warning_types import PytestWarning
+from pytest import collect
 
 
 set_trace = __pytestPDB.set_trace
@@ -54,6 +55,7 @@
     "approx",
     "Class",
     "cmdline",
+    "collect",
     "Collector",
     "deprecated_call",
     "exit",
diff --git a/testing/test_meta.py b/testing/test_meta.py
index e081e2fd56b..1dade035dea 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -39,3 +39,11 @@ def test_no_warnings(module):
         "-c", "import {}".format(module),
     ))
     # fmt: on
+
+
+def test_pytest_collect_attribute(_sys_snapshot):
+    del sys.modules["pytest"]
+
+    import pytest
+
+    assert pytest.collect

From d18a7d7bc086fd87d561fa409ff21c9bed8abe89 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Wed, 26 Feb 2020 17:18:46 +0100
Subject: [PATCH 04/10] Keep _setup_collect_fakemodule, but via __getattr__

---
 src/_pytest/compat.py  | 26 ++++++++++++++++++++++++++
 src/pytest/__init__.py |  9 +++++++--
 src/pytest/collect.py  | 10 ----------
 testing/test_meta.py   | 22 +++++++++++-----------
 4 files changed, 44 insertions(+), 23 deletions(-)
 delete mode 100644 src/pytest/collect.py

diff --git a/src/_pytest/compat.py b/src/_pytest/compat.py
index 8aff8d57da4..043def9efd9 100644
--- a/src/_pytest/compat.py
+++ b/src/_pytest/compat.py
@@ -34,6 +34,7 @@
 
 
 if TYPE_CHECKING:
+    from types import ModuleType  # noqa: F401 (used in type string)
     from typing import Type  # noqa: F401 (used in type string)
 
 
@@ -336,6 +337,31 @@ def safe_isclass(obj: object) -> bool:
         return False
 
 
+COLLECT_FAKEMODULE_ATTRIBUTES = (
+    "Collector",
+    "Module",
+    "Function",
+    "Instance",
+    "Session",
+    "Item",
+    "Class",
+    "File",
+    "_fillfuncargs",
+)
+
+
+def _setup_collect_fakemodule() -> "ModuleType":
+    from types import ModuleType
+    import pytest
+
+    # Types ignored because the module is created dynamically.
+    mod = ModuleType("pytest.collect")  # type: ignore
+    mod.__all__ = []  # type: ignore  # used for setns
+    for attr_name in COLLECT_FAKEMODULE_ATTRIBUTES:
+        setattr(mod, attr_name, getattr(pytest, attr_name))  # type: ignore
+    return mod
+
+
 class CaptureIO(io.TextIOWrapper):
     def __init__(self) -> None:
         super().__init__(io.BytesIO(), encoding="UTF-8", newline="", write_through=True)
diff --git a/src/pytest/__init__.py b/src/pytest/__init__.py
index dab6f543675..aa2157e046f 100644
--- a/src/pytest/__init__.py
+++ b/src/pytest/__init__.py
@@ -44,7 +44,6 @@
 from _pytest.warning_types import PytestUnhandledCoroutineWarning
 from _pytest.warning_types import PytestUnknownMarkWarning
 from _pytest.warning_types import PytestWarning
-from pytest import collect
 
 
 set_trace = __pytestPDB.set_trace
@@ -55,7 +54,6 @@
     "approx",
     "Class",
     "cmdline",
-    "collect",
     "Collector",
     "deprecated_call",
     "exit",
@@ -94,3 +92,10 @@
     "xfail",
     "yield_fixture",
 ]
+
+
+def __getattr__(name):
+    if name == "collect":
+        from _pytest.compat import _setup_collect_fakemodule
+
+        return _setup_collect_fakemodule()
diff --git a/src/pytest/collect.py b/src/pytest/collect.py
deleted file mode 100644
index fce42de5a8e..00000000000
--- a/src/pytest/collect.py
+++ /dev/null
@@ -1,10 +0,0 @@
-"""Fake module for backward compatibility."""
-from . import _fillfuncargs  # noqa: F401
-from . import Class  # noqa: F401
-from . import Collector  # noqa: F401
-from . import File  # noqa: F401
-from . import Function  # noqa: F401
-from . import Instance  # noqa: F401
-from . import Item  # noqa: F401
-from . import Module  # noqa: F401
-from . import Session  # noqa: F401
diff --git a/testing/test_meta.py b/testing/test_meta.py
index 1dade035dea..3ac2269fdcc 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -13,17 +13,11 @@
 
 
 def _modules():
-    extra = [
-        "pytest.collect",
-    ]
-    return (
-        sorted(
-            n
-            for _, n, _ in pkgutil.walk_packages(
-                _pytest.__path__, prefix=_pytest.__name__ + "."
-            )
+    return sorted(
+        n
+        for _, n, _ in pkgutil.walk_packages(
+            _pytest.__path__, prefix=_pytest.__name__ + "."
         )
-        + extra
     )
 
 
@@ -42,8 +36,14 @@ def test_no_warnings(module):
 
 
 def test_pytest_collect_attribute(_sys_snapshot):
+    from types import ModuleType
+
     del sys.modules["pytest"]
 
     import pytest
 
-    assert pytest.collect
+    assert isinstance(pytest.collect, ModuleType)
+    assert pytest.collect.Item is pytest.Item
+
+    with pytest.raises(ImportError):
+        import pytest.collect

From 0089e55fa4f7e04b99ea271a73aff391b95badc9 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Wed, 26 Feb 2020 18:34:27 +0100
Subject: [PATCH 05/10] raise AttributeError

---
 src/pytest/__init__.py | 1 +
 testing/test_meta.py   | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/src/pytest/__init__.py b/src/pytest/__init__.py
index aa2157e046f..5bb9cbb9349 100644
--- a/src/pytest/__init__.py
+++ b/src/pytest/__init__.py
@@ -99,3 +99,4 @@ def __getattr__(name):
         from _pytest.compat import _setup_collect_fakemodule
 
         return _setup_collect_fakemodule()
+    raise AttributeError(name)
diff --git a/testing/test_meta.py b/testing/test_meta.py
index 3ac2269fdcc..7b6c5c25fc5 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -47,3 +47,6 @@ def test_pytest_collect_attribute(_sys_snapshot):
 
     with pytest.raises(ImportError):
         import pytest.collect
+
+    with pytest.raises(AttributeError, match=r"^doesnotexist$"):
+        pytest.doesnotexist

From d371bad39e8121fbac1200479b249699bf012b14 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Thu, 27 Feb 2020 00:38:24 +0100
Subject: [PATCH 06/10] __getattr__ with py37+

---
 src/pytest/__init__.py | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/pytest/__init__.py b/src/pytest/__init__.py
index 5bb9cbb9349..6ea2cf4cf45 100644
--- a/src/pytest/__init__.py
+++ b/src/pytest/__init__.py
@@ -2,6 +2,8 @@
 """
 pytest: unit and functional testing with Python.
 """
+import sys
+
 from _pytest import __version__
 from _pytest.assertion import register_assert_rewrite
 from _pytest.config import cmdline
@@ -45,7 +47,6 @@
 from _pytest.warning_types import PytestUnknownMarkWarning
 from _pytest.warning_types import PytestWarning
 
-
 set_trace = __pytestPDB.set_trace
 
 __all__ = [
@@ -94,9 +95,18 @@
 ]
 
 
-def __getattr__(name):
-    if name == "collect":
-        from _pytest.compat import _setup_collect_fakemodule
+if sys.version_info >= (3, 7):
+
+    def __getattr__(name):
+        if name == "collect":
+            from _pytest.compat import _setup_collect_fakemodule
+
+            return _setup_collect_fakemodule()
+        raise AttributeError(name)
+
+
+else:
+    from _pytest.compat import _setup_collect_fakemodule
 
-        return _setup_collect_fakemodule()
-    raise AttributeError(name)
+    collect = _setup_collect_fakemodule()
+    del _setup_collect_fakemodule

From a762bc5e390b27f6cbd0df8dad9f8654a3876d35 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Thu, 27 Feb 2020 16:31:05 +0100
Subject: [PATCH 07/10] _setup_collect_fakemodule: use references, avoid
 circular import

---
 src/_pytest/compat.py | 37 ++++++++++++++++++-------------------
 1 file changed, 18 insertions(+), 19 deletions(-)

diff --git a/src/_pytest/compat.py b/src/_pytest/compat.py
index 043def9efd9..0688c2c0ecb 100644
--- a/src/_pytest/compat.py
+++ b/src/_pytest/compat.py
@@ -337,28 +337,27 @@ def safe_isclass(obj: object) -> bool:
         return False
 
 
-COLLECT_FAKEMODULE_ATTRIBUTES = (
-    "Collector",
-    "Module",
-    "Function",
-    "Instance",
-    "Session",
-    "Item",
-    "Class",
-    "File",
-    "_fillfuncargs",
-)
-
-
 def _setup_collect_fakemodule() -> "ModuleType":
+    """Setup pytest.collect fake module for backward compatibility."""
     from types import ModuleType
-    import pytest
+    import _pytest.nodes
+
+    collect_fakemodule_attributes = (
+        ("Collector", _pytest.nodes.Collector),
+        ("Module", _pytest.python.Module),
+        ("Function", _pytest.python.Function),
+        ("Instance", _pytest.python.Instance),
+        ("Session", _pytest.main.Session),
+        ("Item", _pytest.nodes.Item),
+        ("Class", _pytest.python.Class),
+        ("File", _pytest.nodes.File),
+        ("_fillfuncargs", _pytest.fixtures.fillfixtures),
+    )
 
-    # Types ignored because the module is created dynamically.
-    mod = ModuleType("pytest.collect")  # type: ignore
-    mod.__all__ = []  # type: ignore  # used for setns
-    for attr_name in COLLECT_FAKEMODULE_ATTRIBUTES:
-        setattr(mod, attr_name, getattr(pytest, attr_name))  # type: ignore
+    mod = ModuleType("pytest.collect")
+    mod.__all__ = []  # type: ignore  # used for setns (obsolete?)
+    for attr_name, value in collect_fakemodule_attributes:
+        setattr(mod, attr_name, value)
     return mod
 
 

From 8cbb5ea114c22b192c218964c6a3deb1ae59de24 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Thu, 27 Feb 2020 17:09:59 +0100
Subject: [PATCH 08/10] testing/conftest.py: add symlink_or_skip

Taken out of https://github.com/pytest-dev/pytest/pull/6733, returning
for existing symlink (should not skip).
---
 testing/conftest.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/testing/conftest.py b/testing/conftest.py
index 90cdcb869fd..f03835e19b2 100644
--- a/testing/conftest.py
+++ b/testing/conftest.py
@@ -1,3 +1,4 @@
+import os
 import re
 import sys
 from typing import List
@@ -136,6 +137,27 @@ def testdir(testdir: Testdir) -> Testdir:
     return testdir
 
 
+@pytest.fixture
+def symlink_or_skip():
+    """Return a function that creates a symlink or raises ``Skip``.
+
+    On Windows `os.symlink` is available, but normal users require special
+    admin privileges to create symlinks.
+    """
+
+    def wrap_os_symlink(src, dst, *args, **kwargs):
+        if os.path.islink(dst):
+            return
+
+        try:
+            os.symlink(src, dst, *args, **kwargs)
+        except OSError as e:
+            pytest.skip("os.symlink({!r}) failed: {!r}".format((src, dst), e))
+        assert os.path.islink(dst)
+
+    return wrap_os_symlink
+
+
 @pytest.fixture(scope="session")
 def color_mapping():
     """Returns a utility class which can replace keys in strings in the form "{NAME}"

From 65610d11e36fe285d1b9ae676260bd7698a6f62b Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Thu, 27 Feb 2020 17:10:55 +0100
Subject: [PATCH 09/10] Add test_pytest_circular_import

---
 testing/test_meta.py | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/testing/test_meta.py b/testing/test_meta.py
index 7b6c5c25fc5..486927c33d5 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -10,6 +10,7 @@
 
 import _pytest
 import pytest
+from _pytest.pytester import Testdir
 
 
 def _modules():
@@ -50,3 +51,18 @@ def test_pytest_collect_attribute(_sys_snapshot):
 
     with pytest.raises(AttributeError, match=r"^doesnotexist$"):
         pytest.doesnotexist
+
+
+def test_pytest_circular_import(testdir: Testdir, symlink_or_skip) -> None:
+    """Importing pytest should not import pytest itself."""
+    import pytest
+    import os.path
+
+    symlink_or_skip(os.path.dirname(pytest.__file__), "another")
+
+    del sys.modules["pytest"]
+
+    testdir.syspathinsert()
+    import another  # noqa: F401
+
+    assert "pytest" not in sys.modules

From b7e4375978c2675ec860d05aced194ac55f1237a Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Thu, 27 Feb 2020 17:16:23 +0100
Subject: [PATCH 10/10] Fix test_pytest_collect_attribute for older Python

---
 testing/test_meta.py | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/testing/test_meta.py b/testing/test_meta.py
index 486927c33d5..6dbc47ddc41 100644
--- a/testing/test_meta.py
+++ b/testing/test_meta.py
@@ -49,8 +49,12 @@ def test_pytest_collect_attribute(_sys_snapshot):
     with pytest.raises(ImportError):
         import pytest.collect
 
-    with pytest.raises(AttributeError, match=r"^doesnotexist$"):
-        pytest.doesnotexist
+    if sys.version_info >= (3, 7):
+        with pytest.raises(AttributeError, match=r"^doesnotexist$"):
+            pytest.doesnotexist
+    else:
+        with pytest.raises(AttributeError, match=r"doesnotexist"):
+            pytest.doesnotexist
 
 
 def test_pytest_circular_import(testdir: Testdir, symlink_or_skip) -> None: