Reword comment

[etc/vim.git] / blib2to3 / pytree.py

diff --git a/blib2to3/pytree.py b/blib2to3/pytree.py
index 693366f7b2e4fb3bba6ad237aefa8bfca7904dc3..6776491cfbf26aa69bdb46977cfeefdff91f4221 100644 (file)
--- a/blib2to3/pytree.py
+++ b/blib2to3/pytree.py
@@ -18,16 +18,21 @@ from io import StringIO
 HUGE = 0x7FFFFFFF  # maximum repeat count, default max
 
 _type_reprs = {}
 HUGE = 0x7FFFFFFF  # maximum repeat count, default max
 
 _type_reprs = {}

+
+

 def type_repr(type_num):
     global _type_reprs
     if not _type_reprs:
         from .pygram import python_symbols
 def type_repr(type_num):
     global _type_reprs
     if not _type_reprs:
         from .pygram import python_symbols

+

         # printing tokens is possible but not as useful
         # from .pgen2 import token // token.__dict__.items():
         for name, val in python_symbols.__dict__.items():
         # printing tokens is possible but not as useful
         # from .pgen2 import token // token.__dict__.items():
         for name, val in python_symbols.__dict__.items():

-            if type(val) == int: _type_reprs[val] = name
+            if type(val) == int:
+                _type_reprs[val] = name

     return _type_reprs.setdefault(type_num, type_num)
 
     return _type_reprs.setdefault(type_num, type_num)
 

+

 class Base(object):
 
     """
 class Base(object):
 
     """


@@ -40,7 +45,7 @@ class Base(object):
     """
 
     # Default values for instance variables
     """
 
     # Default values for instance variables

-    type = None    # int: token number (< 256) or symbol number (>= 256)
+    type = None  # int: token number (< 256) or symbol number (>= 256)

     parent = None  # Parent node pointer, or None
     children = ()  # Tuple of subnodes
     was_changed = False
     parent = None  # Parent node pointer, or None
     children = ()  # Tuple of subnodes
     was_changed = False


@@ -61,7 +66,7 @@ class Base(object):
             return NotImplemented
         return self._eq(other)
 
             return NotImplemented
         return self._eq(other)
 

-    __hash__ = None # For Py3 compatibility.
+    __hash__ = None  # For Py3 compatibility.

 
     def _eq(self, other):
         """
 
     def _eq(self, other):
         """


@@ -115,8 +120,9 @@ class Base(object):
             else:
                 l_children.append(ch)
         assert found, (self.children, self, new)
             else:
                 l_children.append(ch)
         assert found, (self.children, self, new)

-        self.parent.changed()

         self.parent.children = l_children
         self.parent.children = l_children

+        self.parent.changed()
+        self.parent.invalidate_sibling_maps()

         for x in new:
             x.parent = self.parent
         self.parent = None
         for x in new:
             x.parent = self.parent
         self.parent = None


@@ -131,6 +137,8 @@ class Base(object):
         return node.lineno
 
     def changed(self):
         return node.lineno
 
     def changed(self):

+        if self.was_changed:
+            return

         if self.parent:
             self.parent.changed()
         self.was_changed = True
         if self.parent:
             self.parent.changed()
         self.was_changed = True


@@ -143,8 +151,9 @@ class Base(object):
         if self.parent:
             for i, node in enumerate(self.parent.children):
                 if node is self:
         if self.parent:
             for i, node in enumerate(self.parent.children):
                 if node is self:

-                    self.parent.changed()

                     del self.parent.children[i]
                     del self.parent.children[i]

+                    self.parent.changed()
+                    self.parent.invalidate_sibling_maps()

                     self.parent = None
                     return i
 
                     self.parent = None
                     return i
 


@@ -157,13 +166,9 @@ class Base(object):
         if self.parent is None:
             return None
 
         if self.parent is None:
             return None
 

-        # Can't use index(); we need to test by identity
-        for i, child in enumerate(self.parent.children):
-            if child is self:
-                try:
-                    return self.parent.children[i+1]
-                except IndexError:
-                    return None
+        if self.parent.next_sibling_map is None:
+            self.parent.update_sibling_maps()
+        return self.parent.next_sibling_map[id(self)]

 
     @property
     def prev_sibling(self):
 
     @property
     def prev_sibling(self):


@@ -174,12 +179,9 @@ class Base(object):
         if self.parent is None:
             return None
 
         if self.parent is None:
             return None
 

-        # Can't use index(); we need to test by identity
-        for i, child in enumerate(self.parent.children):
-            if child is self:
-                if i == 0:
-                    return None
-                return self.parent.children[i-1]
+        if self.parent.prev_sibling_map is None:
+            self.parent.update_sibling_maps()
+        return self.parent.prev_sibling_map[id(self)]

 
     def leaves(self):
         for child in self.children:
 
     def leaves(self):
         for child in self.children:


@@ -201,17 +203,16 @@ class Base(object):
         return next_sib.prefix
 
     if sys.version_info < (3, 0):
         return next_sib.prefix
 
     if sys.version_info < (3, 0):

+

         def __str__(self):
             return str(self).encode("ascii")
 
         def __str__(self):
             return str(self).encode("ascii")
 

+

 class Node(Base):
 
     """Concrete implementation for interior nodes."""
 
 class Node(Base):
 
     """Concrete implementation for interior nodes."""
 

-    def __init__(self,type, children,
-                 context=None,
-                 prefix=None,
-                 fixers_applied=None):
+    def __init__(self, type, children, context=None, prefix=None, fixers_applied=None):

         """
         Initializer.
 
         """
         Initializer.
 


@@ -226,6 +227,7 @@ class Node(Base):
         for ch in self.children:
             assert ch.parent is None, repr(ch)
             ch.parent = self
         for ch in self.children:
             assert ch.parent is None, repr(ch)
             ch.parent = self

+        self.invalidate_sibling_maps()

         if prefix is not None:
             self.prefix = prefix
         if fixers_applied:
         if prefix is not None:
             self.prefix = prefix
         if fixers_applied:


@@ -235,9 +237,11 @@ class Node(Base):
 
     def __repr__(self):
         """Return a canonical string representation."""
 
     def __repr__(self):
         """Return a canonical string representation."""

-        return "%s(%s, %r)" % (self.__class__.__name__,
-                               type_repr(self.type),
-                               self.children)
+        return "%s(%s, %r)" % (
+            self.__class__.__name__,
+            type_repr(self.type),
+            self.children,
+        )

 
     def __unicode__(self):
         """
 
     def __unicode__(self):
         """


@@ -256,8 +260,11 @@ class Node(Base):
 
     def clone(self):
         """Return a cloned (deep) copy of self."""
 
     def clone(self):
         """Return a cloned (deep) copy of self."""

-        return Node(self.type, [ch.clone() for ch in self.children],
-                    fixers_applied=self.fixers_applied)
+        return Node(
+            self.type,
+            [ch.clone() for ch in self.children],
+            fixers_applied=self.fixers_applied,
+        )

 
     def post_order(self):
         """Return a post-order iterator for the tree."""
 
     def post_order(self):
         """Return a post-order iterator for the tree."""


@@ -294,6 +301,7 @@ class Node(Base):
         self.children[i].parent = None
         self.children[i] = child
         self.changed()
         self.children[i].parent = None
         self.children[i] = child
         self.changed()

+        self.invalidate_sibling_maps()

 
     def insert_child(self, i, child):
         """
 
     def insert_child(self, i, child):
         """


@@ -303,6 +311,7 @@ class Node(Base):
         child.parent = self
         self.children.insert(i, child)
         self.changed()
         child.parent = self
         self.children.insert(i, child)
         self.changed()

+        self.invalidate_sibling_maps()

 
     def append_child(self, child):
         """
 
     def append_child(self, child):
         """


@@ -312,6 +321,21 @@ class Node(Base):
         child.parent = self
         self.children.append(child)
         self.changed()
         child.parent = self
         self.children.append(child)
         self.changed()

+        self.invalidate_sibling_maps()
+
+    def invalidate_sibling_maps(self):
+        self.prev_sibling_map = None
+        self.next_sibling_map = None
+
+    def update_sibling_maps(self):
+        self.prev_sibling_map = _prev = {}
+        self.next_sibling_map = _next = {}
+        previous = None
+        for current in self.children:
+            _prev[id(current)] = previous
+            _next[id(previous)] = current
+            previous = current
+        _next[id(current)] = None

 
 
 class Leaf(Base):
 
 
 class Leaf(Base):


@@ -320,13 +344,10 @@ class Leaf(Base):
 
     # Default values for instance variables
     _prefix = ""  # Whitespace and comments preceding this token in the input
 
     # Default values for instance variables
     _prefix = ""  # Whitespace and comments preceding this token in the input

-    lineno = 0    # Line where this token starts in the input
-    column = 0    # Column where this token tarts in the input
+    lineno = 0  # Line where this token starts in the input
+    column = 0  # Column where this token starts in the input

 
 

-    def __init__(self, type, value,
-                 context=None,
-                 prefix=None,
-                 fixers_applied=[]):
+    def __init__(self, type, value, context=None, prefix=None, fixers_applied=[]):

         """
         Initializer.
 
         """
         Initializer.
 


@@ -345,9 +366,12 @@ class Leaf(Base):
     def __repr__(self):
         """Return a canonical string representation."""
         from .pgen2.token import tok_name
     def __repr__(self):
         """Return a canonical string representation."""
         from .pgen2.token import tok_name

-        return "%s(%s, %r)" % (self.__class__.__name__,
-                               tok_name.get(self.type, self.type),
-                               self.value)
+
+        return "%s(%s, %r)" % (
+            self.__class__.__name__,
+            tok_name.get(self.type, self.type),
+            self.value,
+        )

 
     def __unicode__(self):
         """
 
     def __unicode__(self):
         """


@@ -366,9 +390,12 @@ class Leaf(Base):
 
     def clone(self):
         """Return a cloned (deep) copy of self."""
 
     def clone(self):
         """Return a cloned (deep) copy of self."""

-        return Leaf(self.type, self.value,
-                    (self.prefix, (self.lineno, self.column)),
-                    fixers_applied=self.fixers_applied)
+        return Leaf(
+            self.type,
+            self.value,
+            (self.prefix, (self.lineno, self.column)),
+            fixers_applied=self.fixers_applied,
+        )

 
     def leaves(self):
         yield self
 
     def leaves(self):
         yield self


@@ -393,6 +420,7 @@ class Leaf(Base):
         self.changed()
         self._prefix = prefix
 
         self.changed()
         self._prefix = prefix
 

+

 def convert(gr, raw_node):
     """
     Convert raw node information to a Node or Leaf instance.
 def convert(gr, raw_node):
     """
     Convert raw node information to a Node or Leaf instance.


@@ -429,9 +457,9 @@ class BasePattern(object):
     """
 
     # Defaults for instance variables
     """
 
     # Defaults for instance variables

-    type = None     # Node type (token if < 256, symbol if >= 256)
+    type = None  # Node type (token if < 256, symbol if >= 256)

     content = None  # Optional content matching pattern
     content = None  # Optional content matching pattern

-    name = None     # Optional name used to store match in results dict
+    name = None  # Optional name used to store match in results dict

 
     def __new__(cls, *args, **kwds):
         """Constructor that prevents BasePattern from being instantiated."""
 
     def __new__(cls, *args, **kwds):
         """Constructor that prevents BasePattern from being instantiated."""


@@ -499,7 +527,6 @@ class BasePattern(object):
 
 
 class LeafPattern(BasePattern):
 
 
 class LeafPattern(BasePattern):

-

     def __init__(self, type=None, content=None, name=None):
         """
         Initializer.  Takes optional type, content, and name.
     def __init__(self, type=None, content=None, name=None):
         """
         Initializer.  Takes optional type, content, and name.


@@ -646,7 +673,7 @@ class WildcardPattern(BasePattern):
             # Check sanity of alternatives
             assert len(content), repr(content)  # Can't have zero alternatives
             for alt in content:
             # Check sanity of alternatives
             assert len(content), repr(content)  # Can't have zero alternatives
             for alt in content:

-                assert len(alt), repr(alt) # Can have empty alternatives
+                assert len(alt), repr(alt)  # Can have empty alternatives

         self.content = content
         self.min = min
         self.max = max
         self.content = content
         self.min = min
         self.max = max


@@ -655,20 +682,29 @@ class WildcardPattern(BasePattern):
     def optimize(self):
         """Optimize certain stacked wildcard patterns."""
         subpattern = None
     def optimize(self):
         """Optimize certain stacked wildcard patterns."""
         subpattern = None

-        if (self.content is not None and
-            len(self.content) == 1 and len(self.content[0]) == 1):
+        if (
+            self.content is not None
+            and len(self.content) == 1
+            and len(self.content[0]) == 1
+        ):

             subpattern = self.content[0][0]
         if self.min == 1 and self.max == 1:
             if self.content is None:
                 return NodePattern(name=self.name)
             subpattern = self.content[0][0]
         if self.min == 1 and self.max == 1:
             if self.content is None:
                 return NodePattern(name=self.name)

-            if subpattern is not None and  self.name == subpattern.name:
+            if subpattern is not None and self.name == subpattern.name:

                 return subpattern.optimize()
                 return subpattern.optimize()

-        if (self.min <= 1 and isinstance(subpattern, WildcardPattern) and
-            subpattern.min <= 1 and self.name == subpattern.name):
-            return WildcardPattern(subpattern.content,
-                                   self.min*subpattern.min,
-                                   self.max*subpattern.max,
-                                   subpattern.name)
+        if (
+            self.min <= 1
+            and isinstance(subpattern, WildcardPattern)
+            and subpattern.min <= 1
+            and self.name == subpattern.name
+        ):
+            return WildcardPattern(
+                subpattern.content,
+                self.min * subpattern.min,
+                self.max * subpattern.max,
+                subpattern.name,
+            )

         return self
 
     def match(self, node, results=None):
         return self
 
     def match(self, node, results=None):


@@ -784,7 +820,7 @@ class WildcardPattern(BasePattern):
         if count < self.max:
             for alt in self.content:
                 for c0, r0 in generate_matches(alt, nodes):
         if count < self.max:
             for alt in self.content:
                 for c0, r0 in generate_matches(alt, nodes):

-                    for c1, r1 in self._recursive_matches(nodes[c0:], count+1):
+                    for c1, r1 in self._recursive_matches(nodes[c0:], count + 1):

                         r = {}
                         r.update(r0)
                         r.update(r1)
                         r = {}
                         r.update(r0)
                         r.update(r1)


@@ -792,7 +828,6 @@ class WildcardPattern(BasePattern):
 
 
 class NegatedPattern(BasePattern):
 
 
 class NegatedPattern(BasePattern):

-

     def __init__(self, content=None):
         """
         Initializer.
     def __init__(self, content=None):
         """
         Initializer.