gh-104780: Remove 2to3 program and lib2to3 module (#104781)

* Remove the Tools/scripts/2to3 script.
* Remove the Lib/test/test_lib2to3/ directory.
* Doc/tools/extensions/pyspecific.py: remove the "2to3fixer" object
  type.
* Makefile and PC/layout/main.py no longer compile lib2to3 grammar
  files.
* Update Makefile for 2to3 removal.

1 files changed, 0 insertions, 280 deletions

diff --git a/Lib/lib2to3/btm_utils.py b/Lib/lib2to3/btm_utils.py
deleted file mode 100644
index b61afdb..0000000
--- a/Lib/lib2to3/btm_utils.py
+++ /dev/null
@@ -1,280 +0,0 @@
-"Utility functions used by the btm_matcher module"
-
-from . import pytree
-from .pgen2 import grammar, token
-from .pygram import pattern_symbols, python_symbols
-
-syms = pattern_symbols
-pysyms = python_symbols
-tokens = grammar.opmap
-token_labels = token
-
-TYPE_ANY = -1
-TYPE_ALTERNATIVES = -2
-TYPE_GROUP = -3
-
-class MinNode(object):
-    """This class serves as an intermediate representation of the
-    pattern tree during the conversion to sets of leaf-to-root
-    subpatterns"""
-
-    def __init__(self, type=None, name=None):
-        self.type = type
-        self.name = name
-        self.children = []
-        self.leaf = False
-        self.parent = None
-        self.alternatives = []
-        self.group = []
-
-    def __repr__(self):
-        return str(self.type) + ' ' + str(self.name)
-
-    def leaf_to_root(self):
-        """Internal method. Returns a characteristic path of the
-        pattern tree. This method must be run for all leaves until the
-        linear subpatterns are merged into a single"""
-        node = self
-        subp = []
-        while node:
-            if node.type == TYPE_ALTERNATIVES:
-                node.alternatives.append(subp)
-                if len(node.alternatives) == len(node.children):
-                    #last alternative
-                    subp = [tuple(node.alternatives)]
-                    node.alternatives = []
-                    node = node.parent
-                    continue
-                else:
-                    node = node.parent
-                    subp = None
-                    break
-
-            if node.type == TYPE_GROUP:
-                node.group.append(subp)
-                #probably should check the number of leaves
-                if len(node.group) == len(node.children):
-                    subp = get_characteristic_subpattern(node.group)
-                    node.group = []
-                    node = node.parent
-                    continue
-                else:
-                    node = node.parent
-                    subp = None
-                    break
-
-            if node.type == token_labels.NAME and node.name:
-                #in case of type=name, use the name instead
-                subp.append(node.name)
-            else:
-                subp.append(node.type)
-
-            node = node.parent
-        return subp
-
-    def get_linear_subpattern(self):
-        """Drives the leaf_to_root method. The reason that
-        leaf_to_root must be run multiple times is because we need to
-        reject 'group' matches; for example the alternative form
-        (a | b c) creates a group [b c] that needs to be matched. Since
-        matching multiple linear patterns overcomes the automaton's
-        capabilities, leaf_to_root merges each group into a single
-        choice based on 'characteristic'ity,
-
-        i.e. (a|b c) -> (a|b) if b more characteristic than c
-
-        Returns: The most 'characteristic'(as defined by
-          get_characteristic_subpattern) path for the compiled pattern
-          tree.
-        """
-
-        for l in self.leaves():
-            subp = l.leaf_to_root()
-            if subp:
-                return subp
-
-    def leaves(self):
-        "Generator that returns the leaves of the tree"
-        for child in self.children:
-            yield from child.leaves()
-        if not self.children:
-            yield self
-
-def reduce_tree(node, parent=None):
-    """
-    Internal function. Reduces a compiled pattern tree to an
-    intermediate representation suitable for feeding the
-    automaton. This also trims off any optional pattern elements(like
-    [a], a*).
-    """
-
-    new_node = None
-    #switch on the node type
-    if node.type == syms.Matcher:
-        #skip
-        node = node.children[0]
-
-    if node.type == syms.Alternatives  :
-        #2 cases
-        if len(node.children) <= 2:
-            #just a single 'Alternative', skip this node
-            new_node = reduce_tree(node.children[0], parent)
-        else:
-            #real alternatives
-            new_node = MinNode(type=TYPE_ALTERNATIVES)
-            #skip odd children('|' tokens)
-            for child in node.children:
-                if node.children.index(child)%2:
-                    continue
-                reduced = reduce_tree(child, new_node)
-                if reduced is not None:
-                    new_node.children.append(reduced)
-    elif node.type == syms.Alternative:
-        if len(node.children) > 1:
-
-            new_node = MinNode(type=TYPE_GROUP)
-            for child in node.children:
-                reduced = reduce_tree(child, new_node)
-                if reduced:
-                    new_node.children.append(reduced)
-            if not new_node.children:
-                # delete the group if all of the children were reduced to None
-                new_node = None
-
-        else:
-            new_node = reduce_tree(node.children[0], parent)
-
-    elif node.type == syms.Unit:
-        if (isinstance(node.children[0], pytree.Leaf) and
-            node.children[0].value == '('):
-            #skip parentheses
-            return reduce_tree(node.children[1], parent)
-        if ((isinstance(node.children[0], pytree.Leaf) and
-               node.children[0].value == '[')
-               or
-               (len(node.children)>1 and
-               hasattr(node.children[1], "value") and
-               node.children[1].value == '[')):
-            #skip whole unit if its optional
-            return None
-
-        leaf = True
-        details_node = None
-        alternatives_node = None
-        has_repeater = False
-        repeater_node = None
-        has_variable_name = False
-
-        for child in node.children:
-            if child.type == syms.Details:
-                leaf = False
-                details_node = child
-            elif child.type == syms.Repeater:
-                has_repeater = True
-                repeater_node = child
-            elif child.type == syms.Alternatives:
-                alternatives_node = child
-            if hasattr(child, 'value') and child.value == '=': # variable name
-                has_variable_name = True
-
-        #skip variable name
-        if has_variable_name:
-            #skip variable name, '='
-            name_leaf = node.children[2]
-            if hasattr(name_leaf, 'value') and name_leaf.value == '(':
-                # skip parenthesis
-                name_leaf = node.children[3]
-        else:
-            name_leaf = node.children[0]
-
-        #set node type
-        if name_leaf.type == token_labels.NAME:
-            #(python) non-name or wildcard
-            if name_leaf.value == 'any':
-                new_node = MinNode(type=TYPE_ANY)
-            else:
-                if hasattr(token_labels, name_leaf.value):
-                    new_node = MinNode(type=getattr(token_labels, name_leaf.value))
-                else:
-                    new_node = MinNode(type=getattr(pysyms, name_leaf.value))
-
-        elif name_leaf.type == token_labels.STRING:
-            #(python) name or character; remove the apostrophes from
-            #the string value
-            name = name_leaf.value.strip("'")
-            if name in tokens:
-                new_node = MinNode(type=tokens[name])
-            else:
-                new_node = MinNode(type=token_labels.NAME, name=name)
-        elif name_leaf.type == syms.Alternatives:
-            new_node = reduce_tree(alternatives_node, parent)
-
-        #handle repeaters
-        if has_repeater:
-            if repeater_node.children[0].value == '*':
-                #reduce to None
-                new_node = None
-            elif repeater_node.children[0].value == '+':
-                #reduce to a single occurrence i.e. do nothing
-                pass
-            else:
-                #TODO: handle {min, max} repeaters
-                raise NotImplementedError
-
-        #add children
-        if details_node and new_node is not None:
-            for child in details_node.children[1:-1]:
-                #skip '<', '>' markers
-                reduced = reduce_tree(child, new_node)
-                if reduced is not None:
-                    new_node.children.append(reduced)
-    if new_node:
-        new_node.parent = parent
-    return new_node
-
-
-def get_characteristic_subpattern(subpatterns):
-    """Picks the most characteristic from a list of linear patterns
-    Current order used is:
-    names > common_names > common_chars
-    """
-    if not isinstance(subpatterns, list):
-        return subpatterns
-    if len(subpatterns)==1:
-        return subpatterns[0]
-
-    # first pick out the ones containing variable names
-    subpatterns_with_names = []
-    subpatterns_with_common_names = []
-    common_names = ['in', 'for', 'if' , 'not', 'None']
-    subpatterns_with_common_chars = []
-    common_chars = "[]().,:"
-    for subpattern in subpatterns:
-        if any(rec_test(subpattern, lambda x: type(x) is str)):
-            if any(rec_test(subpattern,
-                            lambda x: isinstance(x, str) and x in common_chars)):
-                subpatterns_with_common_chars.append(subpattern)
-            elif any(rec_test(subpattern,
-                              lambda x: isinstance(x, str) and x in common_names)):
-                subpatterns_with_common_names.append(subpattern)
-
-            else:
-                subpatterns_with_names.append(subpattern)
-
-    if subpatterns_with_names:
-        subpatterns = subpatterns_with_names
-    elif subpatterns_with_common_names:
-        subpatterns = subpatterns_with_common_names
-    elif subpatterns_with_common_chars:
-        subpatterns = subpatterns_with_common_chars
-    # of the remaining subpatterns pick out the longest one
-    return max(subpatterns, key=len)
-
-def rec_test(sequence, test_func):
-    """Tests test_func on all items of sequence and items of included
-    sub-iterables"""
-    for x in sequence:
-        if isinstance(x, (list, tuple)):
-            yield from rec_test(x, test_func)
-        else:
-            yield test_func(x)