Flake8 the code + ensure it for the future.

.travis.yml

@@ -8,13 +8,13 @@ python:
     - pypy-5.4
 env:
     - ENVIRON=py
-    - ENVIRON=isort
+    - ENVIRON=isort,flake8
 matrix:
     exclude:
-        - env: ENVIRON=isort
+        - env: ENVIRON=isort,flake8
     include:
         - python: "3.6"
-          env: ENVIRON=isort
+          env: ENVIRON=isort,flake8
 install:
     - pip install tox coveralls coverage
 script:

setup.cfg

@@ -20,3 +20,8 @@ force_single_line = True
 lines_after_imports = 2
 line_length = 200
 not_skip = __init__.py
+
+[flake8]
+exclude = src/RestrictedPython/tests,
+          src/RestrictedPython/__init__.py,
+          src/RestrictedPython/SelectCompiler.py,

src/RestrictedPython/Eval.py

@@ -13,7 +13,6 @@
 """Restricted Python Expressions."""
 
 from RestrictedPython.RCompile import compile_restricted_eval
-#from RestrictedPython.compile import compile_restricted_eval
 from string import strip
 from string import translate
 
@@ -29,6 +28,7 @@ def default_guarded_getitem(ob, index):
     # No restrictions.
     return ob[index]
 
+
 PROFILE = 0
 
 

src/RestrictedPython/Guards.py

@@ -229,7 +229,8 @@ def __init__(self, ob):
 def _full_write_guard():
     # Nested scope abuse!
     # safetype and Wrapper variables are used by guard()
-    safetype = {dict: True, list: True}.has_key if IS_PY2 else {dict: True, list: True}.keys
+    safetype = ({dict: True, list: True}.has_key if IS_PY2 else
+                {dict: True, list: True}.keys)
     Wrapper = _write_wrapper()
 
     def guard(ob):
@@ -240,16 +241,22 @@ def guard(ob):
         # Hand the object to the Wrapper instance, then return the instance.
         return Wrapper(ob)
     return guard
+
+
 full_write_guard = _full_write_guard()
 
 
 def guarded_setattr(object, name, value):
     setattr(full_write_guard(object), name, value)
+
+
 safe_builtins['setattr'] = guarded_setattr
 
 
 def guarded_delattr(object, name):
     delattr(full_write_guard(object), name)
+
+
 safe_builtins['delattr'] = guarded_delattr
 
 

src/RestrictedPython/Limits.py

@@ -33,18 +33,24 @@ def _limited_range(iFirst, *args):
     if iLen >= RANGELIMIT:
         raise ValueError('range() too large')
     return range(iStart, iEnd, iStep)
+
+
 limited_builtins['range'] = _limited_range
 
 
 def _limited_list(seq):
     if isinstance(seq, str):
         raise TypeError('cannot convert string to list')
     return list(seq)
+
+
 limited_builtins['list'] = _limited_list
 
 
 def _limited_tuple(seq):
     if isinstance(seq, str):
         raise TypeError('cannot convert string to tuple')
     return tuple(seq)
+
+
 limited_builtins['tuple'] = _limited_tuple

src/RestrictedPython/RCompile.py

@@ -22,7 +22,7 @@
 from compiler.pycodegen import AbstractCompileMode
 from compiler.pycodegen import Expression
 from compiler.pycodegen import findOp
-from compiler.pycodegen import FunctionCodeGenerator
+from compiler.pycodegen import FunctionCodeGenerator  # noqa
 from compiler.pycodegen import Interactive
 from compiler.pycodegen import Module
 from compiler.pycodegen import ModuleCodeGenerator
@@ -259,13 +259,13 @@ def parse(self):
         if len(f.code.nodes) > 0:
             stmt1 = f.code.nodes[0]
             if (isinstance(stmt1, c_ast.Discard) and
-                isinstance(stmt1.expr, c_ast.Const) and
-                isinstance(stmt1.expr.value, str)):
+                    isinstance(stmt1.expr, c_ast.Const) and
+                    isinstance(stmt1.expr.value, str)):
                 f.doc = stmt1.expr.value
         # The caller may specify that certain variables are globals
         # so that they can be referenced before a local assignment.
         # The only known example is the variables context, container,
         # script, traverse_subpath in PythonScripts.
         if self.globals:
-            f.code.nodes.insert(0, ast.Global(self.globals))
+            f.code.nodes.insert(0, c_ast.Global(self.globals))
         return tree

src/RestrictedPython/RestrictionMutator.py

@@ -42,6 +42,7 @@ def stmtNode(txt):
     rmLineno(node)
     return node
 
+
 # The security checks are performed by a set of six functions that
 # must be provided by the restricted environment.
 

src/RestrictedPython/Utilities.py

@@ -14,7 +14,6 @@
 import math
 import random
 import string
-import warnings
 
 
 # _old_filters = warnings.filters[:]
@@ -50,6 +49,8 @@ def same_type(arg1, *args):
         if getattr(arg, '__class__', type(arg)) is not t:
             return 0
     return 1
+
+
 utility_builtins['same_type'] = same_type
 
 
@@ -61,6 +62,8 @@ def test(*args):
 
     if length % 2:
         return args[-1]
+
+
 utility_builtins['test'] = test
 
 
@@ -98,4 +101,6 @@ def reorder(s, with_=None, without=()):
             del orig[key]
 
     return result
+
+
 utility_builtins['reorder'] = reorder

src/RestrictedPython/__init__.py

@@ -13,10 +13,10 @@
 """RestrictedPython package."""
 
 # Old API --> Old Import Locations
-#from RestrictedPython.RCompile import compile_restricted
-#from RestrictedPython.RCompile import compile_restricted_eval
-#from RestrictedPython.RCompile import compile_restricted_exec
-#from RestrictedPython.RCompile import compile_restricted_function
+# from RestrictedPython.RCompile import compile_restricted
+# from RestrictedPython.RCompile import compile_restricted_eval
+# from RestrictedPython.RCompile import compile_restricted_exec
+# from RestrictedPython.RCompile import compile_restricted_function
 
 # new API Style
 from RestrictedPython.compile import compile_restricted
@@ -31,4 +31,4 @@
 from RestrictedPython.Utilities import utility_builtins
 
 
-#from RestrictedPython.Eval import RestrictionCapableEval
+# from RestrictedPython.Eval import RestrictionCapableEval

src/RestrictedPython/compile.py

@@ -6,6 +6,8 @@
 
 CompileResult = namedtuple(
     'CompileResult', 'code, errors, warnings, used_names')
+syntax_error_template = (
+    'Line {lineno}: {type}: {msg} in on statement: {statement}')
 
 
 def _compile_restricted_mode(
@@ -30,7 +32,7 @@ def _compile_restricted_mode(
         except (TypeError, ValueError) as e:
             errors.append(str(e))
         except SyntaxError as v:
-            errors.append('Line {lineno}: {type}: {msg} in on statement: {statement}'.format(
+            errors.append(syntax_error_template.format(
                 lineno=v.lineno,
                 type=v.__class__.__name__,
                 msg=v.msg,
@@ -40,8 +42,8 @@ def _compile_restricted_mode(
             policy(errors, warnings, used_names).visit(c_ast)
             if not errors:
                 byte_code = compile(c_ast, filename, mode=mode  # ,
-                                    #flags=flags,
-                                    #dont_inherit=dont_inherit
+                                    # flags=flags,
+                                    # dont_inherit=dont_inherit
                                     )
     return CompileResult(byte_code, tuple(errors), warnings, used_names)
 
@@ -52,6 +54,7 @@ def compile_restricted_exec(
         flags=0,
         dont_inherit=0,
         policy=RestrictingNodeTransformer):
+    """Compile restricted for the mode `exec`."""
     return _compile_restricted_mode(
         source,
         filename=filename,
@@ -67,7 +70,7 @@ def compile_restricted_eval(
         flags=0,
         dont_inherit=0,
         policy=RestrictingNodeTransformer):
-
+    """Compile restricted for the mode `eval`."""
     return _compile_restricted_mode(
         source,
         filename=filename,
@@ -83,6 +86,7 @@ def compile_restricted_single(
         flags=0,
         dont_inherit=0,
         policy=RestrictingNodeTransformer):
+    """Compile restricted for the mode `single`."""
     return _compile_restricted_mode(
         source,
         filename=filename,
@@ -98,7 +102,7 @@ def compile_restricted_function(
         flags=0,
         dont_inherit=0,
         policy=RestrictingNodeTransformer):
-    """Compiles a restricted code object for a function.
+    """Compile a restricted code object for a function.
 
     The function can be reconstituted using the 'new' module:
 

src/RestrictedPython/transformer.py

@@ -107,17 +107,20 @@ def gen_tmp_name(self):
     def error(self, node, info):
         """Record a security error discovered during transformation."""
         lineno = getattr(node, 'lineno', None)
-        self.errors.append('Line {lineno}: {info}'.format(lineno=lineno, info=info))
+        self.errors.append(
+            'Line {lineno}: {info}'.format(lineno=lineno, info=info))
 
     def warn(self, node, info):
         """Record a security error discovered during transformation."""
         lineno = getattr(node, 'lineno', None)
-        self.warnings.append('Line {lineno}: {info}'.format(lineno=lineno, info=info))
+        self.warnings.append(
+            'Line {lineno}: {info}'.format(lineno=lineno, info=info))
 
     def use_name(self, node, info):
         """Record a security error discovered during transformation."""
         lineno = getattr(node, 'lineno', None)
-        self.used_names.append('Line {lineno}: {info}'.format(lineno=lineno, info=info))
+        self.used_names.append(
+            'Line {lineno}: {info}'.format(lineno=lineno, info=info))
 
     def guard_iter(self, node):
         """
@@ -161,7 +164,8 @@ def gen_unpack_spec(self, tpl):
 
         This spec is used to protect sequence unpacking.
         The primary goal of this spec is to tell which elements in a sequence
-        are sequences again. These 'child' sequences have to be protected again.
+        are sequences again. These 'child' sequences have to be protected
+        again.
 
         For example there is a sequence like this:
             (a, (b, c), (d, (e, f))) = g
@@ -307,14 +311,15 @@ def gen_none_node(self):
 
     def gen_lambda(self, args, body):
         return ast.Lambda(
-            args=ast.arguments(args=args, vararg=None, kwarg=None, defaults=[]),
+            args=ast.arguments(
+                args=args, vararg=None, kwarg=None, defaults=[]),
             body=body)
 
     def gen_del_stmt(self, name_to_del):
         return ast.Delete(targets=[ast.Name(name_to_del, ast.Del())])
 
     def transform_slice(self, slice_):
-        """Transforms slices into function parameters.
+        """Transform slices into function parameters.
 
         ast.Slice nodes are only allowed within a ast.Subscript node.
         To use a slice as an argument of ast.Call it has to be converted.
@@ -433,7 +438,8 @@ def inject_print_collector(self, node, position=0):
         printed_used = self.print_info.printed_used
 
         if print_used or printed_used:
-            # Add '_print = _print_(_getattr_)' add the top of a function/module.
+            # Add '_print = _print_(_getattr_)' add the top of a
+            # function/module.
             _print = ast.Assign(
                 targets=[ast.Name('_print', ast.Store())],
                 value=ast.Call(
@@ -1281,7 +1287,7 @@ def visit_withitem(self, node):
     # Function and class definitions
 
     def visit_FunctionDef(self, node):
-        """Checks a function defintion.
+        """Check a function defintion.
 
         Checks the name of the function and the arguments.
         """
@@ -1301,7 +1307,8 @@ def visit_FunctionDef(self, node):
         unpacks = []
         for index, arg in enumerate(list(node.args.args)):
             if isinstance(arg, ast.Tuple):
-                tmp_target, unpack = self.gen_unpack_wrapper(node, arg, 'param')
+                tmp_target, unpack = self.gen_unpack_wrapper(
+                    node, arg, 'param')
 
                 # Replace the tuple with a single (temporary) parameter.
                 node.args.args[index] = tmp_target

tox.ini

@@ -1,5 +1,6 @@
 [tox]
 envlist =
+    flake8,
     coverage-clean,
     py27,
     py34,
@@ -8,7 +9,6 @@ envlist =
     pypy,
     coverage-report,
     isort,
-    #flake8,
 skip_missing_interpreters = False
 
 [testenv]