[Python-checkins] cpython: Issue #17636: Circular imports involving relative imports are now supported.
antoine.pitrou
python-checkins at python.org
Mon Oct 13 20:21:32 CEST 2014
https://hg.python.org/cpython/rev/fded07a2d616
changeset: 93026:fded07a2d616
parent: 93023:c0224ff67cdd
user: Antoine Pitrou <solipsis at pitrou.net>
date: Mon Oct 13 20:19:45 2014 +0200
summary:
Issue #17636: Circular imports involving relative imports are now supported.
files:
Lib/test/test_import.py | 42 +++++++++-
Lib/test/test_import/__main__.py | 3 +
Lib/test/test_import/data/circular_imports/basic.py | 2 +
Lib/test/test_import/data/circular_imports/basic2.py | 1 +
Lib/test/test_import/data/circular_imports/indirect.py | 1 +
Lib/test/test_import/data/circular_imports/rebinding.py | 3 +
Lib/test/test_import/data/circular_imports/rebinding2.py | 3 +
Lib/test/test_import/data/circular_imports/subpackage.py | 2 +
Lib/test/test_import/data/circular_imports/subpkg/subpackage2.py | 2 +
Lib/test/test_import/data/circular_imports/subpkg/util.py | 2 +
Lib/test/test_import/data/circular_imports/util.py | 2 +
Misc/NEWS | 3 +
Python/ceval.c | 22 ++++-
13 files changed, 85 insertions(+), 3 deletions(-)
diff --git a/Lib/test/test_import.py b/Lib/test/test_import/__init__.py
rename from Lib/test/test_import.py
rename to Lib/test/test_import/__init__.py
--- a/Lib/test/test_import.py
+++ b/Lib/test/test_import/__init__.py
@@ -568,7 +568,7 @@
def test_relimport_star(self):
# This will import * from .test_import.
- from . import relimport
+ from .. import relimport
self.assertTrue(hasattr(relimport, "RelativeImportTests"))
def test_issue3221(self):
@@ -1068,6 +1068,46 @@
__isolated=False)
+class CircularImportTests(unittest.TestCase):
+
+ """See the docstrings of the modules being imported for the purpose of the
+ test."""
+
+ def tearDown(self):
+ """Make sure no modules pre-exist in sys.modules which are being used to
+ test."""
+ for key in list(sys.modules.keys()):
+ if key.startswith('test.test_import.data.circular_imports'):
+ del sys.modules[key]
+
+ def test_direct(self):
+ try:
+ import test.test_import.data.circular_imports.basic
+ except ImportError:
+ self.fail('circular import through relative imports failed')
+
+ def test_indirect(self):
+ try:
+ import test.test_import.data.circular_imports.indirect
+ except ImportError:
+ self.fail('relative import in module contributing to circular '
+ 'import failed')
+
+ def test_subpackage(self):
+ try:
+ import test.test_import.data.circular_imports.subpackage
+ except ImportError:
+ self.fail('circular import involving a subpackage failed')
+
+ def test_rebinding(self):
+ try:
+ import test.test_import.data.circular_imports.rebinding as rebinding
+ except ImportError:
+ self.fail('circular import with rebinding of module attribute failed')
+ from test.test_import.data.circular_imports.subpkg import util
+ self.assertIs(util.util, rebinding.util)
+
+
if __name__ == '__main__':
# Test needs to be a package, so we can do relative imports.
unittest.main()
diff --git a/Lib/test/test_import/__main__.py b/Lib/test/test_import/__main__.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/__main__.py
@@ -0,0 +1,3 @@
+import unittest
+
+unittest.main('test.test_import')
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/basic.py b/Lib/test/test_import/data/circular_imports/basic.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/basic.py
@@ -0,0 +1,2 @@
+"""Circular imports through direct, relative imports."""
+from . import basic2
diff --git a/Lib/test/test_import/data/circular_imports/basic2.py b/Lib/test/test_import/data/circular_imports/basic2.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/basic2.py
@@ -0,0 +1,1 @@
+from . import basic
diff --git a/Lib/test/test_import/data/circular_imports/indirect.py b/Lib/test/test_import/data/circular_imports/indirect.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/indirect.py
@@ -0,0 +1,1 @@
+from . import basic, basic2
diff --git a/Lib/test/test_import/data/circular_imports/rebinding.py b/Lib/test/test_import/data/circular_imports/rebinding.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/rebinding.py
@@ -0,0 +1,3 @@
+"""Test the binding of names when a circular import shares the same name as an
+attribute."""
+from .rebinding2 import util
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/rebinding2.py b/Lib/test/test_import/data/circular_imports/rebinding2.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/rebinding2.py
@@ -0,0 +1,3 @@
+from .subpkg import util
+from . import rebinding
+util = util.util
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/subpackage.py b/Lib/test/test_import/data/circular_imports/subpackage.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/subpackage.py
@@ -0,0 +1,2 @@
+"""Circular import involving a sub-package."""
+from .subpkg import subpackage2
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/subpkg/subpackage2.py b/Lib/test/test_import/data/circular_imports/subpkg/subpackage2.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/subpkg/subpackage2.py
@@ -0,0 +1,2 @@
+#from .util import util
+from .. import subpackage
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/subpkg/util.py b/Lib/test/test_import/data/circular_imports/subpkg/util.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/subpkg/util.py
@@ -0,0 +1,2 @@
+def util():
+ pass
\ No newline at end of file
diff --git a/Lib/test/test_import/data/circular_imports/util.py b/Lib/test/test_import/data/circular_imports/util.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_import/data/circular_imports/util.py
@@ -0,0 +1,2 @@
+def util():
+ pass
\ No newline at end of file
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,9 @@
Core and Builtins
-----------------
+- Issue #17636: Circular imports involving relative imports are now
+ supported.
+
- Issue #22604: Fix assertion error in debug mode when dividing a complex
number by (nan+0j).
diff --git a/Python/ceval.c b/Python/ceval.c
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -4693,11 +4693,29 @@
import_from(PyObject *v, PyObject *name)
{
PyObject *x;
+ _Py_IDENTIFIER(__name__);
+ PyObject *fullmodname, *pkgname;
x = PyObject_GetAttr(v, name);
- if (x == NULL && PyErr_ExceptionMatches(PyExc_AttributeError)) {
+ if (x != NULL || !PyErr_ExceptionMatches(PyExc_AttributeError))
+ return x;
+ /* Issue #17636: in case this failed because of a circular relative
+ import, try to fallback on reading the module directly from
+ sys.modules. */
+ PyErr_Clear();
+ pkgname = _PyObject_GetAttrId(v, &PyId___name__);
+ if (pkgname == NULL)
+ return NULL;
+ fullmodname = PyUnicode_FromFormat("%U.%U", pkgname, name);
+ Py_DECREF(pkgname);
+ if (fullmodname == NULL)
+ return NULL;
+ x = PyDict_GetItem(PyImport_GetModuleDict(), fullmodname);
+ if (x == NULL)
PyErr_Format(PyExc_ImportError, "cannot import name %R", name);
- }
+ else
+ Py_INCREF(x);
+ Py_DECREF(fullmodname);
return x;
}
--
Repository URL: https://hg.python.org/cpython
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