Get version using AST

Incorrectly installed package will crash during import

CHANGELOG.rst

@@ -1,5 +1,9 @@
 CHANGELOG
 =========
+Version 2.4.1
+-------------
+* Use ast for version extraction and do not use danger of if's in `__init__.py` - installed without dependencies package should crash on import.
+
 Version 2.4.0
 -------------
 * PyPy3 correct support and python 3.3 external asyncio.

logwrap/__init__.py

@@ -24,29 +24,24 @@
 
 from __future__ import absolute_import
 
-try:
-    import six
-
-    from ._repr_utils import PrettyFormat, pretty_repr, pretty_str
-
-    # pylint: disable=no-name-in-module
-    if six.PY3:  # pragma: no cover
-        from ._log_wrap3 import logwrap, LogWrap
-    else:  # pragma: no cover
-        from ._log_wrap2 import logwrap, LogWrap
-    # pylint: enable=no-name-in-module
-
-    __all__ = (
-        'LogWrap',
-        'logwrap',
-        'PrettyFormat',
-        'pretty_repr',
-        'pretty_str'
-    )
-
-except ImportError:  # pragma: no cover
-    # Package is not installed
-    six = PrettyFormat = pretty_repr = pretty_str = logwrap = LogWrap = None
-
-__version__ = '2.4.0'
+import six
+
+from ._repr_utils import PrettyFormat, pretty_repr, pretty_str
+
+# pylint: disable=no-name-in-module
+if six.PY3:  # pragma: no cover
+    from ._log_wrap3 import logwrap, LogWrap
+else:  # pragma: no cover
+    from ._log_wrap2 import logwrap, LogWrap
+# pylint: enable=no-name-in-module
+
+__all__ = (
+    'LogWrap',
+    'logwrap',
+    'PrettyFormat',
+    'pretty_repr',
+    'pretty_str'
+)
+
+__version__ = '2.4.1'
 __author__ = "Alexey Stepanov <penguinolog@gmail.com>"

setup.cfg

@@ -1,6 +1,5 @@
 [metadata]
 name = logwrap
-version = attr: logwrap.__version__
 url = https://github.com/penguinolog/logwrap
 author = Alexey Stepanov
 author_email = penguinolog@gmail.com

setup.py

@@ -16,10 +16,69 @@
 
 """logwrap decorator for human-readable logging of command arguments."""
 
+import ast
+import collections
+import os.path
+
 import setuptools
+import six
+
+with open(
+    os.path.join(
+        os.path.dirname(__file__),
+        'logwrap', '__init__.py'
+    )
+) as f:
+    source = f.read()
+
+
+# noinspection PyUnresolvedReferences
+def get_simple_vars_from_src(src):
+    """Get simple (string/number/boolean and None) assigned values from source.
+
+    :param src: Source code
+    :type src: str
+    :rtype: collections.OrderedDict
+    """
+    ast_string = (ast.Str,)
+    if six.PY3:
+        ast_string += (ast.Bytes,)
+
+    tree = ast.parse(src)
+
+    result = collections.OrderedDict()
+
+    for node in ast.iter_child_nodes(tree):
+        if not isinstance(node, ast.Assign):  # We parse assigns only
+            continue
+        for tgt in node.targets:
+            if isinstance(
+                tgt, ast.Name
+            ) and isinstance(
+                tgt.ctx, ast.Store
+            ):
+                if isinstance(node.value, ast.Num):  # Number, incl. complex
+                    result[tgt.id] = node.value.n
+                elif isinstance(node.value, ast_string):  # String, incl bytes
+                    result[tgt.id] = node.value.s
+                elif isinstance(  # NameConstant in python < 3.4
+                    node.value, ast.Name
+                ) and isinstance(
+                    node.value.ctx, ast.Load  # Read constant
+                ):
+                    # pylint: disable=eval-used
+                    result[tgt.id] = eval(node.value.id, {}, {}) in {}  # nosec
+                    # pylint: enable=eval-used
+                elif six.PY34 and isinstance(node.value, ast.NameConstant):
+                    result[tgt.id] = node.value.value
+    return result
+
+
+variables = get_simple_vars_from_src(source)
 
 setuptools.setup(
     name='logwrap',
+    version=variables['__version__'],
     extras_require={
         ':python_version == "2.7"': [
             'funcsigs>=1.0',