Add future 0.18.2

lib/libpasteurize/fixes/fix_metaclass.py

@@ -0,0 +1,78 @@
+u"""
+Fixer for (metaclass=X) -> __metaclass__ = X
+Some semantics (see PEP 3115) may be altered in the translation."""
+
+from lib2to3 import fixer_base
+from lib2to3.fixer_util import Name, syms, Node, Leaf, Newline, find_root
+from lib2to3.pygram import token
+from libfuturize.fixer_util import indentation, suitify
+# from ..fixer_util import Name, syms, Node, Leaf, Newline, find_root, indentation, suitify
+
+def has_metaclass(parent):
+    results = None
+    for node in parent.children:
+        kids = node.children
+        if node.type == syms.argument:
+            if kids[0] == Leaf(token.NAME, u"metaclass") and \
+                kids[1] == Leaf(token.EQUAL, u"=") and \
+                kids[2]:
+                #Hack to avoid "class X(=):" with this case.
+                results = [node] + kids
+                break
+        elif node.type == syms.arglist:
+            # Argument list... loop through it looking for:
+            # Node(*, [*, Leaf(token.NAME, u"metaclass"), Leaf(token.EQUAL, u"="), Leaf(*, *)]
+            for child in node.children:
+                if results: break
+                if child.type == token.COMMA:
+                    #Store the last comma, which precedes the metaclass
+                    comma = child
+                elif type(child) == Node:
+                    meta = equal = name = None
+                    for arg in child.children:
+                        if arg == Leaf(token.NAME, u"metaclass"):
+                            #We have the (metaclass) part
+                            meta = arg
+                        elif meta and arg == Leaf(token.EQUAL, u"="):
+                            #We have the (metaclass=) part
+                            equal = arg
+                        elif meta and equal:
+                            #Here we go, we have (metaclass=X)
+                            name = arg
+                            results = (comma, meta, equal, name)
+                            break
+    return results
+
+
+class FixMetaclass(fixer_base.BaseFix):
+
+    PATTERN = u"""
+    classdef<any*>
+    """
+
+    def transform(self, node, results):
+        meta_results = has_metaclass(node)
+        if not meta_results: return
+        for meta in meta_results:
+            meta.remove()
+        target = Leaf(token.NAME, u"__metaclass__")
+        equal = Leaf(token.EQUAL, u"=", prefix=u" ")
+        # meta is the last item in what was returned by has_metaclass(): name
+        name = meta
+        name.prefix = u" "
+        stmt_node = Node(syms.atom, [target, equal, name])
+
+        suitify(node)
+        for item in node.children:
+            if item.type == syms.suite:
+                for stmt in item.children:
+                    if stmt.type == token.INDENT:
+                        # Insert, in reverse order, the statement, a newline,
+                        # and an indent right after the first indented line
+                        loc = item.children.index(stmt) + 1
+                        # Keep consistent indentation form
+                        ident = Leaf(token.INDENT, stmt.value)
+                        item.insert_child(loc, ident)
+                        item.insert_child(loc, Newline())
+                        item.insert_child(loc, stmt_node)
+                        break