EcchiShell v1.0

lib64

python2.7

lib2to3

suite => simple_stmt => expr_stmt => Leaf('__meta') 2) clsdef => simple_stmt => expr_stmt => Leaf('__meta') """ for node in parent.children: if node.type == syms.suite: return has_metaclass(node) elif node.type == syms.simple_stmt and node.children: expr_node = node.children[0] if expr_node.type == syms.expr_stmt and expr_node.children: left_side = expr_node.children[0] if isinstance(left_side, Leaf) and \ left_side.value == '__metaclass__': return True return False def fixup_parse_tree(cls_node): """ one-line classes don't get a suite in the parse tree so we add one to normalize the tree """ for node in cls_node.children: if node.type == syms.suite: # already in the preferred format, do nothing return # !%@#! oneliners have no suite node, we have to fake one up for i, node in enumerate(cls_node.children): if node.type == token.COLON: break else: raise ValueError("No class suite and no ':'!") # move everything into a suite node suite = Node(syms.suite, []) while cls_node.children[i+1:]: move_node = cls_node.children[i+1] suite.append_child(move_node.clone()) move_node.remove() cls_node.append_child(suite) node = suite def fixup_simple_stmt(parent, i, stmt_node): """ if there is a semi-colon all the parts count as part of the same simple_stmt. We just want the __metaclass__ part so we move everything efter the semi-colon into its own simple_stmt node """ for semi_ind, node in enumerate(stmt_node.children): if node.type == token.SEMI: # *sigh* break else: return node.remove() # kill the semicolon new_expr = Node(syms.expr_stmt, []) new_stmt = Node(syms.simple_stmt, [new_expr]) while stmt_node.children[semi_ind:]: move_node = stmt_node.children[semi_ind] new_expr.append_child(move_node.clone()) move_node.remove() parent.insert_child(i, new_stmt) new_leaf1 = new_stmt.children[0].children[0] old_leaf1 = stmt_node.children[0].children[0] new_leaf1.prefix = old_leaf1.prefix def remove_trailing_newline(node): if node.children and node.children[-1].type == token.NEWLINE: node.children[-1].remove() def find_metas(cls_node): # find the suite node (Mmm, sweet nodes) for node in cls_node.children: if node.type == syms.suite: break else: raise ValueError("No class suite!") # look for simple_stmt[ expr_stmt[ Leaf('__metaclass__') ] ] for i, simple_node in list(enumerate(node.children)): if simple_node.type == syms.simple_stmt and simple_node.children: expr_node = simple_node.children[0] if expr_node.type == syms.expr_stmt and expr_node.children: # Check if the expr_node is a simple assignment. left_node = expr_node.children[0] if isinstance(left_node, Leaf) and \ left_node.value == u'__metaclass__': # We found a assignment to __metaclass__. fixup_simple_stmt(node, i, simple_node) remove_trailing_newline(simple_node) yield (node, i, simple_node) def fixup_indent(suite): """ If an INDENT is followed by a thing with a prefix then nuke the prefix Otherwise we get in trouble when removing __metaclass__ at suite start """ kids = suite.children[::-1] # find the first indent while kids: node = kids.pop() if node.type == token.INDENT: break # find the first Leaf while kids: node = kids.pop() if isinstance(node, Leaf) and node.type != token.DEDENT: if node.prefix: node.prefix = u'' return else: kids.extend(node.children[::-1]) class FixMetaclass(fixer_base.BaseFix): BM_compatible = True PATTERN = """ classdef """ def transform(self, node, results): if not has_metaclass(node): return fixup_parse_tree(node) # find metaclasses, keep the last one last_metaclass = None for suite, i, stmt in find_metas(node): last_metaclass = stmt stmt.remove() text_type = node.children[0].type # always Leaf(nnn, 'class') # figure out what kind of classdef we have if len(node.children) == 7: # Node(classdef, ['class', 'name', '(', arglist, ')', ':', suite]) # 0 1 2 3 4 5 6 if node.children[3].type == syms.arglist: arglist = node.children[3] # Node(classdef, ['class', 'name', '(', 'Parent', ')', ':', suite]) else: parent = node.children[3].clone() arglist = Node(syms.arglist, [parent]) node.set_child(3, arglist) elif len(node.children) == 6: # Node(classdef, ['class', 'name', '(', ')', ':', suite]) # 0 1 2 3 4 5 arglist = Node(syms.arglist, []) node.insert_child(3, arglist) elif len(node.children) == 4: # Node(classdef, ['class', 'name', ':', suite]) # 0 1 2 3 arglist = Node(syms.arglist, []) node.insert_child(2, Leaf(token.RPAR, u')')) node.insert_child(2, arglist) node.insert_child(2, Leaf(token.LPAR, u'(')) else: raise ValueError("Unexpected class definition") # now stick the metaclass in the arglist meta_txt = last_metaclass.children[0].children[0] meta_txt.value = 'metaclass' orig_meta_prefix = meta_txt.prefix if arglist.children: arglist.append_child(Leaf(token.COMMA, u',')) meta_txt.prefix = u' ' else: meta_txt.prefix = u'' # compact the expression "metaclass = Meta" -> "metaclass=Meta" expr_stmt = last_metaclass.children[0] assert expr_stmt.type == syms.expr_stmt expr_stmt.children[1].prefix = u'' expr_stmt.children[2].prefix = u'' arglist.append_child(last_metaclass) fixup_indent(suite) # check for empty suite if not suite.children: # one-liner that was just __metaclass_ suite.remove() pass_leaf = Leaf(text_type, u'pass') pass_leaf.prefix = orig_meta_prefix node.append_child(pass_leaf) node.append_child(Leaf(token.NEWLINE, u'\n')) elif len(suite.children) > 1 and \ (suite.children[-2].type == token.INDENT and suite.children[-1].type == token.DEDENT): # there was only one line in the class body and it was __metaclass__ pass_leaf = Leaf(text_type, u'pass') suite.insert_child(-1, pass_leaf) suite.insert_child(-1, Leaf(token.NEWLINE, u'\n'))