bpo-29546: Improve from-import error message with location (#103)

bpo-29546: Improve from-import error message with location
This commit is contained in:
Matthias Bussonnier 2017-02-22 07:06:50 -08:00 committed by Barry Warsaw
parent d37c068e69
commit 1bc156430b
4 changed files with 39 additions and 5 deletions

View File

@ -83,6 +83,9 @@ Other Language Changes
whitespace, not only spaces.
(Contributed by Robert Xiao in :issue:`28927`.)
* :exc:`ImportError` now displays module name and module ``__file__`` path when
``from ... import ...`` fails. :issue:`29546`.
New Modules
===========

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@ -85,6 +85,15 @@ class ImportTests(unittest.TestCase):
from os import i_dont_exist
self.assertEqual(cm.exception.name, 'os')
self.assertEqual(cm.exception.path, os.__file__)
self.assertRegex(str(cm.exception), "cannot import name 'i_dont_exist' from 'os' \(.*/Lib/os.py\)")
def test_from_import_missing_attr_has_name_and_so_path(self):
import _opcode
with self.assertRaises(ImportError) as cm:
from _opcode import i_dont_exist
self.assertEqual(cm.exception.name, '_opcode')
self.assertEqual(cm.exception.path, _opcode.__file__)
self.assertRegex(str(cm.exception), "cannot import name 'i_dont_exist' from '_opcode' \(.*\.(so|dll)\)")
def test_from_import_missing_attr_has_name(self):
with self.assertRaises(ImportError) as cm:
@ -365,9 +374,12 @@ class ImportTests(unittest.TestCase):
module_name = 'test_from_import_AttributeError'
self.addCleanup(unload, module_name)
sys.modules[module_name] = AlwaysAttributeError()
with self.assertRaises(ImportError):
with self.assertRaises(ImportError) as cm:
from test_from_import_AttributeError import does_not_exist
self.assertEqual(str(cm.exception),
"cannot import name 'does_not_exist' from '<unknown module name>' (unknown location)")
@skip_if_dont_write_bytecode
class FilePermissionTests(unittest.TestCase):

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@ -24,6 +24,8 @@ Core and Builtins
- bpo-29546: Set the 'path' and 'name' attribute on ImportError for ``from ... import ...``.
- bpo-29546: Improve from-import error message with location
- Issue #29319: Prevent RunMainFromImporter overwriting sys.path[0].
- Issue #29337: Fixed possible BytesWarning when compare the code objects.

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@ -4995,7 +4995,7 @@ import_from(PyObject *v, PyObject *name)
{
PyObject *x;
_Py_IDENTIFIER(__name__);
PyObject *fullmodname, *pkgname, *pkgpath;
PyObject *fullmodname, *pkgname, *pkgpath, *pkgname_or_unknown;
x = PyObject_GetAttr(v, name);
if (x != NULL || !PyErr_ExceptionMatches(PyExc_AttributeError))
@ -5009,7 +5009,6 @@ import_from(PyObject *v, PyObject *name)
goto error;
}
fullmodname = PyUnicode_FromFormat("%U.%U", pkgname, name);
Py_DECREF(pkgname);
if (fullmodname == NULL) {
return NULL;
}
@ -5018,18 +5017,36 @@ import_from(PyObject *v, PyObject *name)
if (x == NULL) {
goto error;
}
Py_DECREF(pkgname);
Py_INCREF(x);
return x;
error:
pkgpath = PyModule_GetFilenameObject(v);
if (pkgname == NULL) {
pkgname_or_unknown = PyUnicode_FromString("<unknown module name>");
if (pkgname_or_unknown == NULL) {
Py_XDECREF(pkgpath);
return NULL;
}
} else {
pkgname_or_unknown = pkgname;
}
if (pkgpath == NULL || !PyUnicode_Check(pkgpath)) {
PyErr_Clear();
PyErr_SetImportError(PyUnicode_FromFormat("cannot import name %R", name), pkgname, NULL);
PyErr_SetImportError(
PyUnicode_FromFormat("cannot import name %R from %R (unknown location)",
name, pkgname_or_unknown),
pkgname, NULL);
} else {
PyErr_SetImportError(PyUnicode_FromFormat("cannot import name %R", name), pkgname, pkgpath);
PyErr_SetImportError(
PyUnicode_FromFormat("cannot import name %R from %R (%S)",
name, pkgname_or_unknown, pkgpath),
pkgname, pkgpath);
}
Py_XDECREF(pkgname_or_unknown);
Py_XDECREF(pkgpath);
return NULL;
}