parse2.py, pysource.py: add buildclass nonterminal to structure tree

better and make more similar to Python3
load.py: handle magic errors better
main.py: correct use when passing a .py instead of a .pyc better and a message
err when file not found.
pysource.py: fix up main docstring; code moved from main.py

test/simple_source/def/01_class.py

@@ -8,8 +8,8 @@
 #   classdef ::= LOAD_CONST expr mkfunc CALL_FUNCTION_0 BUILD_CLASS designator
 #   mkfunc ::= LOAD_CONST MAKE_FUNCTION_0
 
-class A:
+# class A:
-    pass
-
-# class B(Exception):
 #     pass
+
+class B(Exception):
+    pass

uncompyle6/load.py

@@ -70,8 +70,12 @@ def load_module(filename):
         try:
             version = float(magics.versions[magic])
         except KeyError:
+            if len(magic) >= 2:
                 raise ImportError("Unknown magic number %s in %s" %
                                 (ord(magic[0])+256*ord(magic[1]), filename))
+            else:
+                raise ImportError("Bad magic number: '%s'" % magic)
+
         if not (2.5 <= version <= 2.7) and not (3.2 <= version <= 3.4):
             raise ImportError("This is a Python %s file! Only "
                               "Python 2.5 to 2.7 and 3.2 to 3.4 files are supported."

uncompyle6/main.py

@@ -1,5 +1,5 @@
 from __future__ import print_function
-import os, sys
+import inspect, os, sys
 
 from uncompyle6.disas import check_object_path
 from uncompyle6 import verify
@@ -13,6 +13,8 @@ def uncompyle(version, co, out=None, showasm=False, showast=False,
     disassembles and deparses a given code block 'co'
     """
 
+    assert inspect.iscode(co)
+
     # store final output stream for case of error
     real_out = out or sys.stdout
     print('# Python %s' % version, file=real_out)
@@ -21,28 +23,18 @@ def uncompyle(version, co, out=None, showasm=False, showast=False,
               file=real_out)
 
     try:
-        deparsed = pysource.deparse_code(version, co, out, showasm, showast, showgrammar)
+        pysource.deparse_code(version, co, out, showasm, showast, showgrammar)
     except pysource.ParserError as e :  # parser failed, dump disassembly
         print(e, file=real_out)
         raise
 
-    # FIXME: remove duplicate code from deparse_code
-    try:
-        if deparsed.ast[0][0] == pysource.ASSIGN_DOC_STRING(co.co_consts[0]):
-            deparsed.print_docstring('', co.co_consts[0])
-            del deparsed.ast[0]
-        if deparsed.ast[-1] == pysource.RETURN_NONE:
-            deparsed.ast.pop() # remove last node
-            # todo: if empty, add 'pass'
-    except:
-        pass
-
 def uncompyle_file(filename, outstream=None, showasm=False, showast=False,
                    showgrammar=False):
     """
     decompile Python byte-code file (.pyc)
     """
-    check_object_path(filename)
+
+    filename = check_object_path(filename)
     version, magic_int, co = load_module(filename)
     if type(co) == list:
         for con in co:
@@ -119,7 +111,7 @@ def main(in_base, out_base, files, codes, outfile=None,
             else:
                 sys.stderr.write("\n# %s" % sys.exc_info()[1])
                 sys.stderr.write("\n# Can't uncompile %s\n" % infile)
-        else: # uncompile successfull
+        else: # uncompile successful
             if outfile:
                 outstream.close()
                 if do_verify:
@@ -137,6 +129,13 @@ def main(in_base, out_base, files, codes, outfile=None,
                         if not outfile:
                             print("### Error Verifiying %s" % filename,  file=sys.stderr)
                             print(e, file=sys.stderr)
+                            pass
+                        pass
+                pass
+            elif do_verify:
+                print("\n### uncompile successful, but no file to compare against",
+                      file=sys.stderr)
+                pass
             else:
                 okay_files += 1
                 if not outfile:

uncompyle6/parsers/parse2.py

@@ -351,8 +351,10 @@ class Python2Parser(PythonParser):
 
         kwarg   ::= LOAD_CONST expr
 
-        classdef ::= LOAD_CONST expr mkfunc
+        classdef ::= buildclass designator
-                    CALL_FUNCTION_0 BUILD_CLASS designator
+
+        buildclass ::= LOAD_CONST expr mkfunc
+                     CALL_FUNCTION_0 BUILD_CLASS
 
         stmt ::= classdefdeco
         classdefdeco ::= classdefdeco1 designator

uncompyle6/semantics/pysource.py

@@ -1054,22 +1054,25 @@ class Walker(GenericASTTraversal, object):
 
         cclass = self.currentclass
         if self.version > 3.0:
-            self.currentclass = str(node[1][1].pattr)
+            buildclass = node[1]
+            self.currentclass = str(buildclass[1].pattr)
         else:
-            self.currentclass = str(node[0].pattr)
+            buildclass = node[0]
+            self.currentclass = str(buildclass[0].pattr)
 
         self.write('\n\n')
         self.write(self.indent, 'class ', self.currentclass)
-        self.print_super_classes(node)
+
+        self.print_super_classes(buildclass)
         self.print_(':')
 
         # class body
         self.indentMore()
 
         if self.version > 3.0:
-            self.build_class(node[1][0].attr)
+            self.build_class(buildclass[0].attr)
         else:
-            self.build_class(node[2][-2].attr)
+            self.build_class(buildclass[-3][0].attr)
         self.indentLess()
 
         self.currentclass = cclass
@@ -1568,9 +1571,19 @@ def deparse_code(version, co, out=sys.stdout, showasm=False, showast=False,
 
     del tokens # save memory
 
-    # convert leading '__doc__ = "..." into doc string
     deparsed.mod_globs = find_globals(deparsed.ast, set())
 
+    # convert leading '__doc__ = "..." into doc string
+    try:
+        if deparsed.ast[0][0] == ASSIGN_DOC_STRING(co.co_consts[0]):
+            deparsed.print_docstring('', co.co_consts[0])
+            del deparsed.ast[0]
+        if deparsed.ast[-1] == RETURN_NONE:
+            deparsed.ast.pop() # remove last node
+            # todo: if empty, add 'pass'
+    except:
+        pass
+
     # What we've been waiting for: Generate source from AST!
     deparsed.gen_source(deparsed.ast, customize)