Refactor: Add import_object()

sphinx/ext/autodoc/__init__.py

@@ -14,9 +14,8 @@
 import re
 import sys
 import inspect
-import traceback
 
-from six import PY2, iterkeys, iteritems, itervalues, text_type, class_types, string_types
+from six import iterkeys, iteritems, itervalues, text_type, class_types, string_types
 
 from docutils import nodes
 from docutils.utils import assemble_option_dict
@@ -24,7 +23,7 @@ from docutils.parsers.rst import Directive
 from docutils.statemachine import ViewList
 
 import sphinx
-from sphinx.ext.autodoc.importer import mock, import_module
+from sphinx.ext.autodoc.importer import mock, import_object
 from sphinx.ext.autodoc.importer import _MockImporter  # to keep compatibility  # NOQA
 from sphinx.ext.autodoc.inspector import format_annotation, formatargspec  # to keep compatibility  # NOQA
 from sphinx.util import rpartition, force_decode
@@ -384,56 +383,15 @@ class Documenter(object):
 
         Returns True if successful, False if an error occurred.
         """
-        if self.objpath:
-            logger.debug('[autodoc] from %s import %s',
-                         self.modname, '.'.join(self.objpath))
-        # always enable mock import hook
-        # it will do nothing if autodoc_mock_imports is empty
         with mock(self.env.config.autodoc_mock_imports):
             try:
-                logger.debug('[autodoc] import %s', self.modname)
-                obj = import_module(self.modname, self.env.config.autodoc_warningiserror)
-                parent = None
-                self.module = obj
-                logger.debug('[autodoc] => %r', obj)
-                for part in self.objpath:
-                    parent = obj
-                    logger.debug('[autodoc] getattr(_, %r)', part)
-                    obj = self.get_attr(obj, part)
-                    logger.debug('[autodoc] => %r', obj)
-                    self.object_name = part
-                self.parent = parent
-                self.object = obj
+                ret = import_object(self.modname, self.objpath, self.objtype,
+                                    attrgetter=self.get_attr,
+                                    warningiserror=self.env.config.autodoc_warningiserror)
+                self.module, self.parent, self.object_name, self.object = ret
                 return True
-            except (AttributeError, ImportError) as exc:
-                if self.objpath:
-                    errmsg = 'autodoc: failed to import %s %r from module %r' % \
-                             (self.objtype, '.'.join(self.objpath), self.modname)
-                else:
-                    errmsg = 'autodoc: failed to import %s %r' % \
-                             (self.objtype, self.fullname)
-
-                if isinstance(exc, ImportError):
-                    # import_module() raises ImportError having real exception obj and
-                    # traceback
-                    real_exc, traceback_msg = exc.args
-                    if isinstance(real_exc, SystemExit):
-                        errmsg += ('; the module executes module level statement ' +
-                                   'and it might call sys.exit().')
-                    elif isinstance(real_exc, ImportError):
-                        errmsg += ('; the following exception was raised:\n%s' %
-                                   real_exc.args[0])
-                    else:
-                        errmsg += ('; the following exception was raised:\n%s' %
-                                   traceback_msg)
-                else:
-                    errmsg += ('; the following exception was raised:\n%s' %
-                               traceback.format_exc())
-
-                if PY2:
-                    errmsg = errmsg.decode('utf-8')  # type: ignore
-                logger.debug(errmsg)
-                self.directive.warn(errmsg)
+            except ImportError as exc:
+                self.directive.warn(exc.args[0])
                 self.env.note_reread()
                 return False
 

sphinx/ext/autodoc/importer.py

@@ -15,11 +15,14 @@ import traceback
 import contextlib
 from types import FunctionType, MethodType, ModuleType
 
+from six import PY2
+
 from sphinx.util import logging
+from sphinx.util.inspect import safe_getattr
 
 if False:
     # For type annotation
-    from typing import Any, Generator, List, Set  # NOQA
+    from typing import Any, Callable, Generator, List, Set  # NOQA
 
 logger = logging.getLogger(__name__)
 
@@ -144,3 +147,50 @@ def import_module(modname, warningiserror=False):
         # Importing modules may cause any side effects, including
         # SystemExit, so we need to catch all errors.
         raise ImportError(exc, traceback.format_exc())
+
+
+def import_object(modname, objpath, objtype='', attrgetter=safe_getattr, warningiserror=False):
+    # type: (str, List[unicode], str, Callable[[Any, unicode], Any]) -> Any
+    if objpath:
+        logger.debug('[autodoc] from %s import %s', modname, '.'.join(objpath))
+    else:
+        logger.debug('[autodoc] import %s', modname)
+
+    try:
+        module = import_module(modname, warningiserror=warningiserror)
+        logger.debug('[autodoc] => %r', module)
+        obj = module
+        parent = None
+        object_name = None
+        for attrname in objpath:
+            parent = obj
+            logger.debug('[autodoc] getattr(_, %r)', attrname)
+            obj = attrgetter(obj, attrname)
+            logger.debug('[autodoc] => %r', obj)
+            object_name = attrname
+        return [module, parent, object_name, obj]
+    except (AttributeError, ImportError) as exc:
+        if objpath:
+            errmsg = ('autodoc: failed to import %s %r from module %r' %
+                      (objtype, '.'.join(objpath), modname))
+        else:
+            errmsg = 'autodoc: failed to import %s %r' % (objtype, modname)
+
+        if isinstance(exc, ImportError):
+            # import_module() raises ImportError having real exception obj and
+            # traceback
+            real_exc, traceback_msg = exc.args
+            if isinstance(real_exc, SystemExit):
+                errmsg += ('; the module executes module level statement '
+                           'and it might call sys.exit().')
+            elif isinstance(real_exc, ImportError):
+                errmsg += '; the following exception was raised:\n%s' % real_exc.args[0]
+            else:
+                errmsg += '; the following exception was raised:\n%s' % traceback_msg
+        else:
+            errmsg += '; the following exception was raised:\n%s' % traceback.format_exc()
+
+        if PY2:
+            errmsg = errmsg.decode('utf-8')  # type: ignore
+        logger.debug(errmsg)
+        raise ImportError(errmsg)