diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/libfuturize/fixes/fix_division_safe.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/libfuturize/fixes/fix_division_safe.py | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/libfuturize/fixes/fix_division_safe.py b/.venv/lib/python3.12/site-packages/libfuturize/fixes/fix_division_safe.py new file mode 100644 index 00000000..65c8c1da --- /dev/null +++ b/.venv/lib/python3.12/site-packages/libfuturize/fixes/fix_division_safe.py @@ -0,0 +1,109 @@ +""" +For the ``future`` package. + +Adds this import line: + + from __future__ import division + +at the top and changes any old-style divisions to be calls to +past.utils.old_div so the code runs as before on Py2.6/2.7 and has the same +behaviour on Py3. + +If "from __future__ import division" is already in effect, this fixer does +nothing. +""" + +import re +from lib2to3.fixer_util import Leaf, Node, Comma +from lib2to3 import fixer_base +from libfuturize.fixer_util import (token, future_import, touch_import_top, + wrap_in_fn_call) + + +def match_division(node): + u""" + __future__.division redefines the meaning of a single slash for division, + so we match that and only that. + """ + slash = token.SLASH + return node.type == slash and not node.next_sibling.type == slash and \ + not node.prev_sibling.type == slash + +const_re = re.compile('^[0-9]*[.][0-9]*$') + +def is_floaty(node): + return _is_floaty(node.prev_sibling) or _is_floaty(node.next_sibling) + + +def _is_floaty(expr): + if isinstance(expr, list): + expr = expr[0] + + if isinstance(expr, Leaf): + # If it's a leaf, let's see if it's a numeric constant containing a '.' + return const_re.match(expr.value) + elif isinstance(expr, Node): + # If the expression is a node, let's see if it's a direct cast to float + if isinstance(expr.children[0], Leaf): + return expr.children[0].value == u'float' + return False + + +class FixDivisionSafe(fixer_base.BaseFix): + # BM_compatible = True + run_order = 4 # this seems to be ignored? + + _accept_type = token.SLASH + + PATTERN = """ + term<(not('/') any)+ '/' ((not('/') any))> + """ + + def start_tree(self, tree, name): + """ + Skip this fixer if "__future__.division" is already imported. + """ + super(FixDivisionSafe, self).start_tree(tree, name) + self.skip = "division" in tree.future_features + + def match(self, node): + u""" + Since the tree needs to be fixed once and only once if and only if it + matches, we can start discarding matches after the first. + """ + if node.type == self.syms.term: + matched = False + skip = False + children = [] + for child in node.children: + if skip: + skip = False + continue + if match_division(child) and not is_floaty(child): + matched = True + + # Strip any leading space for the first number: + children[0].prefix = u'' + + children = [wrap_in_fn_call("old_div", + children + [Comma(), child.next_sibling.clone()], + prefix=node.prefix)] + skip = True + else: + children.append(child.clone()) + if matched: + # In Python 2.6, `Node` does not have the fixers_applied attribute + # https://github.com/python/cpython/blob/8493c0cd66cfc181ac1517268a74f077e9998701/Lib/lib2to3/pytree.py#L235 + if hasattr(Node, "fixers_applied"): + return Node(node.type, children, fixers_applied=node.fixers_applied) + else: + return Node(node.type, children) + + return False + + def transform(self, node, results): + if self.skip: + return + future_import(u"division", node) + touch_import_top(u'past.utils', u'old_div', node) + return results |