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		b723c8be07
		
			
		
	
	
	
	
		
			
			The implementation does not create anymore local functions which reduces the overhead for small inputs. Some other calls are inlined into a single `_convert_literal` function. We have a gain of 10-20% for small inputs and only 1-2% for bigger inputs.
		
			
				
	
	
		
			693 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			693 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """
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| The `ast` module helps Python applications to process trees of the Python
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| abstract syntax grammar.  The abstract syntax itself might change with
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| each Python release; this module helps to find out programmatically what
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| the current grammar looks like and allows modifications of it.
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| 
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| An abstract syntax tree can be generated by passing `ast.PyCF_ONLY_AST` as
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| a flag to the `compile()` builtin function or by using the `parse()`
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| function from this module.  The result will be a tree of objects whose
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| classes all inherit from `ast.AST`.
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| 
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| A modified abstract syntax tree can be compiled into a Python code object
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| using the built-in `compile()` function.
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| 
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| Additionally various helper functions are provided that make working with
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| the trees simpler.  The main intention of the helper functions and this
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| module in general is to provide an easy to use interface for libraries
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| that work tightly with the python syntax (template engines for example).
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| 
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| :copyright: Copyright 2008 by Armin Ronacher.
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| :license: Python License.
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| """
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| from _ast import *
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| 
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| 
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| def parse(source, filename='<unknown>', mode='exec', *,
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|           type_comments=False, feature_version=None, optimize=-1):
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|     """
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|     Parse the source into an AST node.
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|     Equivalent to compile(source, filename, mode, PyCF_ONLY_AST).
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|     Pass type_comments=True to get back type comments where the syntax allows.
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|     """
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|     flags = PyCF_ONLY_AST
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|     if optimize > 0:
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|         flags |= PyCF_OPTIMIZED_AST
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|     if type_comments:
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|         flags |= PyCF_TYPE_COMMENTS
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|     if feature_version is None:
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|         feature_version = -1
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|     elif isinstance(feature_version, tuple):
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|         major, minor = feature_version  # Should be a 2-tuple.
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|         if major != 3:
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|             raise ValueError(f"Unsupported major version: {major}")
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|         feature_version = minor
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|     # Else it should be an int giving the minor version for 3.x.
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|     return compile(source, filename, mode, flags,
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|                    _feature_version=feature_version, optimize=optimize)
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| 
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| 
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| def literal_eval(node_or_string):
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|     """
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|     Evaluate an expression node or a string containing only a Python
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|     expression.  The string or node provided may only consist of the following
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|     Python literal structures: strings, bytes, numbers, tuples, lists, dicts,
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|     sets, booleans, and None.
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| 
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|     Caution: A complex expression can overflow the C stack and cause a crash.
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|     """
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|     if isinstance(node_or_string, str):
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|         node_or_string = parse(node_or_string.lstrip(" \t"), mode='eval').body
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|     elif isinstance(node_or_string, Expression):
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|         node_or_string = node_or_string.body
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|     return _convert_literal(node_or_string)
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| 
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| 
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| def _convert_literal(node):
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|     """
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|     Used by `literal_eval` to convert an AST node into a value.
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|     """
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|     if isinstance(node, Constant):
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|         return node.value
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|     if isinstance(node, Dict) and len(node.keys) == len(node.values):
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|         return dict(zip(
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|             map(_convert_literal, node.keys),
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|             map(_convert_literal, node.values),
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|         ))
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|     if isinstance(node, Tuple):
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|         return tuple(map(_convert_literal, node.elts))
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|     if isinstance(node, List):
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|         return list(map(_convert_literal, node.elts))
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|     if isinstance(node, Set):
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|         return set(map(_convert_literal, node.elts))
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|     if (
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|         isinstance(node, Call) and isinstance(node.func, Name)
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|         and node.func.id == 'set' and node.args == node.keywords == []
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|     ):
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|         return set()
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|     if (
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|         isinstance(node, UnaryOp)
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|         and isinstance(node.op, (UAdd, USub))
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|         and isinstance(node.operand, Constant)
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|         and type(operand := node.operand.value) in (int, float, complex)
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|     ):
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|         if isinstance(node.op, UAdd):
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|             return + operand
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|         else:
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|             return - operand
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|     if (
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|         isinstance(node, BinOp)
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|         and isinstance(node.op, (Add, Sub))
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|         and isinstance(node.left, (Constant, UnaryOp))
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|         and isinstance(node.right, Constant)
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|         and type(left := _convert_literal(node.left)) in (int, float)
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|         and type(right := _convert_literal(node.right)) is complex
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|     ):
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|         if isinstance(node.op, Add):
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|             return left + right
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|         else:
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|             return left - right
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|     msg = "malformed node or string"
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|     if lno := getattr(node, 'lineno', None):
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|         msg += f' on line {lno}'
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|     raise ValueError(msg + f': {node!r}')
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| 
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| 
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| def dump(
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|     node, annotate_fields=True, include_attributes=False,
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|     *,
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|     indent=None, show_empty=False,
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| ):
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|     """
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|     Return a formatted dump of the tree in node.  This is mainly useful for
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|     debugging purposes.  If annotate_fields is true (by default),
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|     the returned string will show the names and the values for fields.
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|     If annotate_fields is false, the result string will be more compact by
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|     omitting unambiguous field names.  Attributes such as line
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|     numbers and column offsets are not dumped by default.  If this is wanted,
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|     include_attributes can be set to true.  If indent is a non-negative
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|     integer or string, then the tree will be pretty-printed with that indent
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|     level. None (the default) selects the single line representation.
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|     If show_empty is False, then empty lists and fields that are None
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|     will be omitted from the output for better readability.
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|     """
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|     def _format(node, level=0):
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|         if indent is not None:
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|             level += 1
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|             prefix = '\n' + indent * level
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|             sep = ',\n' + indent * level
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|         else:
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|             prefix = ''
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|             sep = ', '
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|         if isinstance(node, AST):
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|             cls = type(node)
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|             args = []
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|             args_buffer = []
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|             allsimple = True
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|             keywords = annotate_fields
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|             for name in node._fields:
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|                 try:
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|                     value = getattr(node, name)
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|                 except AttributeError:
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|                     keywords = True
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|                     continue
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|                 if value is None and getattr(cls, name, ...) is None:
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|                     keywords = True
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|                     continue
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|                 if not show_empty:
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|                     if value == []:
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|                         field_type = cls._field_types.get(name, object)
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|                         if getattr(field_type, '__origin__', ...) is list:
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|                             if not keywords:
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|                                 args_buffer.append(repr(value))
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|                             continue
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|                     elif isinstance(value, Load):
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|                         field_type = cls._field_types.get(name, object)
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|                         if field_type is expr_context:
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|                             if not keywords:
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|                                 args_buffer.append(repr(value))
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|                             continue
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|                     if not keywords:
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|                         args.extend(args_buffer)
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|                         args_buffer = []
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|                 value, simple = _format(value, level)
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|                 allsimple = allsimple and simple
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|                 if keywords:
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|                     args.append('%s=%s' % (name, value))
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|                 else:
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|                     args.append(value)
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|             if include_attributes and node._attributes:
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|                 for name in node._attributes:
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|                     try:
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|                         value = getattr(node, name)
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|                     except AttributeError:
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|                         continue
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|                     if value is None and getattr(cls, name, ...) is None:
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|                         continue
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|                     value, simple = _format(value, level)
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|                     allsimple = allsimple and simple
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|                     args.append('%s=%s' % (name, value))
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|             if allsimple and len(args) <= 3:
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|                 return '%s(%s)' % (node.__class__.__name__, ', '.join(args)), not args
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|             return '%s(%s%s)' % (node.__class__.__name__, prefix, sep.join(args)), False
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|         elif isinstance(node, list):
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|             if not node:
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|                 return '[]', True
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|             return '[%s%s]' % (prefix, sep.join(_format(x, level)[0] for x in node)), False
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|         return repr(node), True
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| 
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|     if not isinstance(node, AST):
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|         raise TypeError('expected AST, got %r' % node.__class__.__name__)
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|     if indent is not None and not isinstance(indent, str):
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|         indent = ' ' * indent
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|     return _format(node)[0]
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| 
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| 
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| def copy_location(new_node, old_node):
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|     """
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|     Copy source location (`lineno`, `col_offset`, `end_lineno`, and `end_col_offset`
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|     attributes) from *old_node* to *new_node* if possible, and return *new_node*.
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|     """
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|     for attr in 'lineno', 'col_offset', 'end_lineno', 'end_col_offset':
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|         if attr in old_node._attributes and attr in new_node._attributes:
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|             value = getattr(old_node, attr, None)
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|             # end_lineno and end_col_offset are optional attributes, and they
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|             # should be copied whether the value is None or not.
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|             if value is not None or (
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|                 hasattr(old_node, attr) and attr.startswith("end_")
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|             ):
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|                 setattr(new_node, attr, value)
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|     return new_node
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| 
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| 
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| def fix_missing_locations(node):
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|     """
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|     When you compile a node tree with compile(), the compiler expects lineno and
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|     col_offset attributes for every node that supports them.  This is rather
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|     tedious to fill in for generated nodes, so this helper adds these attributes
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|     recursively where not already set, by setting them to the values of the
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|     parent node.  It works recursively starting at *node*.
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|     """
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|     def _fix(node, lineno, col_offset, end_lineno, end_col_offset):
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|         if 'lineno' in node._attributes:
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|             if not hasattr(node, 'lineno'):
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|                 node.lineno = lineno
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|             else:
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|                 lineno = node.lineno
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|         if 'end_lineno' in node._attributes:
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|             if getattr(node, 'end_lineno', None) is None:
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|                 node.end_lineno = end_lineno
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|             else:
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|                 end_lineno = node.end_lineno
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|         if 'col_offset' in node._attributes:
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|             if not hasattr(node, 'col_offset'):
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|                 node.col_offset = col_offset
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|             else:
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|                 col_offset = node.col_offset
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|         if 'end_col_offset' in node._attributes:
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|             if getattr(node, 'end_col_offset', None) is None:
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|                 node.end_col_offset = end_col_offset
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|             else:
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|                 end_col_offset = node.end_col_offset
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|         for child in iter_child_nodes(node):
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|             _fix(child, lineno, col_offset, end_lineno, end_col_offset)
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|     _fix(node, 1, 0, 1, 0)
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|     return node
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| 
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| 
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| def increment_lineno(node, n=1):
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|     """
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|     Increment the line number and end line number of each node in the tree
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|     starting at *node* by *n*. This is useful to "move code" to a different
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|     location in a file.
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|     """
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|     for child in walk(node):
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|         # TypeIgnore is a special case where lineno is not an attribute
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|         # but rather a field of the node itself.
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|         if isinstance(child, TypeIgnore):
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|             child.lineno = getattr(child, 'lineno', 0) + n
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|             continue
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| 
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|         if 'lineno' in child._attributes:
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|             child.lineno = getattr(child, 'lineno', 0) + n
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|         if (
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|             "end_lineno" in child._attributes
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|             and (end_lineno := getattr(child, "end_lineno", 0)) is not None
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|         ):
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|             child.end_lineno = end_lineno + n
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|     return node
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| 
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| 
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| def iter_fields(node):
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|     """
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|     Yield a tuple of ``(fieldname, value)`` for each field in ``node._fields``
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|     that is present on *node*.
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|     """
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|     for field in node._fields:
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|         try:
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|             yield field, getattr(node, field)
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|         except AttributeError:
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|             pass
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| 
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| 
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| def iter_child_nodes(node):
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|     """
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|     Yield all direct child nodes of *node*, that is, all fields that are nodes
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|     and all items of fields that are lists of nodes.
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|     """
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|     for name, field in iter_fields(node):
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|         if isinstance(field, AST):
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|             yield field
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|         elif isinstance(field, list):
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|             for item in field:
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|                 if isinstance(item, AST):
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|                     yield item
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| 
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| 
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| def get_docstring(node, clean=True):
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|     """
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|     Return the docstring for the given node or None if no docstring can
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|     be found.  If the node provided does not have docstrings a TypeError
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|     will be raised.
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| 
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|     If *clean* is `True`, all tabs are expanded to spaces and any whitespace
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|     that can be uniformly removed from the second line onwards is removed.
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|     """
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|     if not isinstance(node, (AsyncFunctionDef, FunctionDef, ClassDef, Module)):
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|         raise TypeError("%r can't have docstrings" % node.__class__.__name__)
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|     if not(node.body and isinstance(node.body[0], Expr)):
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|         return None
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|     node = node.body[0].value
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|     if isinstance(node, Constant) and isinstance(node.value, str):
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|         text = node.value
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|     else:
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|         return None
 | |
|     if clean:
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|         import inspect
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|         text = inspect.cleandoc(text)
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|     return text
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| 
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| 
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| _line_pattern = None
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| def _splitlines_no_ff(source, maxlines=None):
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|     """Split a string into lines ignoring form feed and other chars.
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| 
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|     This mimics how the Python parser splits source code.
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|     """
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|     global _line_pattern
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|     if _line_pattern is None:
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|         # lazily computed to speedup import time of `ast`
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|         import re
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|         _line_pattern = re.compile(r"(.*?(?:\r\n|\n|\r|$))")
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| 
 | |
|     lines = []
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|     for lineno, match in enumerate(_line_pattern.finditer(source), 1):
 | |
|         if maxlines is not None and lineno > maxlines:
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|             break
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|         lines.append(match[0])
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|     return lines
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| 
 | |
| 
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| def _pad_whitespace(source):
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|     r"""Replace all chars except '\f\t' in a line with spaces."""
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|     result = ''
 | |
|     for c in source:
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|         if c in '\f\t':
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|             result += c
 | |
|         else:
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|             result += ' '
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|     return result
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| 
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| 
 | |
| def get_source_segment(source, node, *, padded=False):
 | |
|     """Get source code segment of the *source* that generated *node*.
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| 
 | |
|     If some location information (`lineno`, `end_lineno`, `col_offset`,
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|     or `end_col_offset`) is missing, return None.
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| 
 | |
|     If *padded* is `True`, the first line of a multi-line statement will
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|     be padded with spaces to match its original position.
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|     """
 | |
|     try:
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|         if node.end_lineno is None or node.end_col_offset is None:
 | |
|             return None
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|         lineno = node.lineno - 1
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|         end_lineno = node.end_lineno - 1
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|         col_offset = node.col_offset
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|         end_col_offset = node.end_col_offset
 | |
|     except AttributeError:
 | |
|         return None
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| 
 | |
|     lines = _splitlines_no_ff(source, maxlines=end_lineno+1)
 | |
|     if end_lineno == lineno:
 | |
|         return lines[lineno].encode()[col_offset:end_col_offset].decode()
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| 
 | |
|     if padded:
 | |
|         padding = _pad_whitespace(lines[lineno].encode()[:col_offset].decode())
 | |
|     else:
 | |
|         padding = ''
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| 
 | |
|     first = padding + lines[lineno].encode()[col_offset:].decode()
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|     last = lines[end_lineno].encode()[:end_col_offset].decode()
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|     lines = lines[lineno+1:end_lineno]
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| 
 | |
|     lines.insert(0, first)
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|     lines.append(last)
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|     return ''.join(lines)
 | |
| 
 | |
| 
 | |
| def walk(node):
 | |
|     """
 | |
|     Recursively yield all descendant nodes in the tree starting at *node*
 | |
|     (including *node* itself), in no specified order.  This is useful if you
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|     only want to modify nodes in place and don't care about the context.
 | |
|     """
 | |
|     from collections import deque
 | |
|     todo = deque([node])
 | |
|     while todo:
 | |
|         node = todo.popleft()
 | |
|         todo.extend(iter_child_nodes(node))
 | |
|         yield node
 | |
| 
 | |
| 
 | |
| def compare(
 | |
|     a,
 | |
|     b,
 | |
|     /,
 | |
|     *,
 | |
|     compare_attributes=False,
 | |
| ):
 | |
|     """Recursively compares two ASTs.
 | |
| 
 | |
|     compare_attributes affects whether AST attributes are considered
 | |
|     in the comparison. If compare_attributes is False (default), then
 | |
|     attributes are ignored. Otherwise they must all be equal. This
 | |
|     option is useful to check whether the ASTs are structurally equal but
 | |
|     might differ in whitespace or similar details.
 | |
|     """
 | |
| 
 | |
|     sentinel = object()  # handle the possibility of a missing attribute/field
 | |
| 
 | |
|     def _compare(a, b):
 | |
|         # Compare two fields on an AST object, which may themselves be
 | |
|         # AST objects, lists of AST objects, or primitive ASDL types
 | |
|         # like identifiers and constants.
 | |
|         if isinstance(a, AST):
 | |
|             return compare(
 | |
|                 a,
 | |
|                 b,
 | |
|                 compare_attributes=compare_attributes,
 | |
|             )
 | |
|         elif isinstance(a, list):
 | |
|             # If a field is repeated, then both objects will represent
 | |
|             # the value as a list.
 | |
|             if len(a) != len(b):
 | |
|                 return False
 | |
|             for a_item, b_item in zip(a, b):
 | |
|                 if not _compare(a_item, b_item):
 | |
|                     return False
 | |
|             else:
 | |
|                 return True
 | |
|         else:
 | |
|             return type(a) is type(b) and a == b
 | |
| 
 | |
|     def _compare_fields(a, b):
 | |
|         if a._fields != b._fields:
 | |
|             return False
 | |
|         for field in a._fields:
 | |
|             a_field = getattr(a, field, sentinel)
 | |
|             b_field = getattr(b, field, sentinel)
 | |
|             if a_field is sentinel and b_field is sentinel:
 | |
|                 # both nodes are missing a field at runtime
 | |
|                 continue
 | |
|             if a_field is sentinel or b_field is sentinel:
 | |
|                 # one of the node is missing a field
 | |
|                 return False
 | |
|             if not _compare(a_field, b_field):
 | |
|                 return False
 | |
|         else:
 | |
|             return True
 | |
| 
 | |
|     def _compare_attributes(a, b):
 | |
|         if a._attributes != b._attributes:
 | |
|             return False
 | |
|         # Attributes are always ints.
 | |
|         for attr in a._attributes:
 | |
|             a_attr = getattr(a, attr, sentinel)
 | |
|             b_attr = getattr(b, attr, sentinel)
 | |
|             if a_attr is sentinel and b_attr is sentinel:
 | |
|                 # both nodes are missing an attribute at runtime
 | |
|                 continue
 | |
|             if a_attr != b_attr:
 | |
|                 return False
 | |
|         else:
 | |
|             return True
 | |
| 
 | |
|     if type(a) is not type(b):
 | |
|         return False
 | |
|     if not _compare_fields(a, b):
 | |
|         return False
 | |
|     if compare_attributes and not _compare_attributes(a, b):
 | |
|         return False
 | |
|     return True
 | |
| 
 | |
| 
 | |
| class NodeVisitor(object):
 | |
|     """
 | |
|     A node visitor base class that walks the abstract syntax tree and calls a
 | |
|     visitor function for every node found.  This function may return a value
 | |
|     which is forwarded by the `visit` method.
 | |
| 
 | |
|     This class is meant to be subclassed, with the subclass adding visitor
 | |
|     methods.
 | |
| 
 | |
|     Per default the visitor functions for the nodes are ``'visit_'`` +
 | |
|     class name of the node.  So a `TryFinally` node visit function would
 | |
|     be `visit_TryFinally`.  This behavior can be changed by overriding
 | |
|     the `visit` method.  If no visitor function exists for a node
 | |
|     (return value `None`) the `generic_visit` visitor is used instead.
 | |
| 
 | |
|     Don't use the `NodeVisitor` if you want to apply changes to nodes during
 | |
|     traversing.  For this a special visitor exists (`NodeTransformer`) that
 | |
|     allows modifications.
 | |
|     """
 | |
| 
 | |
|     def visit(self, node):
 | |
|         """Visit a node."""
 | |
|         method = 'visit_' + node.__class__.__name__
 | |
|         visitor = getattr(self, method, self.generic_visit)
 | |
|         return visitor(node)
 | |
| 
 | |
|     def generic_visit(self, node):
 | |
|         """Called if no explicit visitor function exists for a node."""
 | |
|         for field, value in iter_fields(node):
 | |
|             if isinstance(value, list):
 | |
|                 for item in value:
 | |
|                     if isinstance(item, AST):
 | |
|                         self.visit(item)
 | |
|             elif isinstance(value, AST):
 | |
|                 self.visit(value)
 | |
| 
 | |
| 
 | |
| class NodeTransformer(NodeVisitor):
 | |
|     """
 | |
|     A :class:`NodeVisitor` subclass that walks the abstract syntax tree and
 | |
|     allows modification of nodes.
 | |
| 
 | |
|     The `NodeTransformer` will walk the AST and use the return value of the
 | |
|     visitor methods to replace or remove the old node.  If the return value of
 | |
|     the visitor method is ``None``, the node will be removed from its location,
 | |
|     otherwise it is replaced with the return value.  The return value may be the
 | |
|     original node in which case no replacement takes place.
 | |
| 
 | |
|     Here is an example transformer that rewrites all occurrences of name lookups
 | |
|     (``foo``) to ``data['foo']``::
 | |
| 
 | |
|        class RewriteName(NodeTransformer):
 | |
| 
 | |
|            def visit_Name(self, node):
 | |
|                return Subscript(
 | |
|                    value=Name(id='data', ctx=Load()),
 | |
|                    slice=Constant(value=node.id),
 | |
|                    ctx=node.ctx
 | |
|                )
 | |
| 
 | |
|     Keep in mind that if the node you're operating on has child nodes you must
 | |
|     either transform the child nodes yourself or call the :meth:`generic_visit`
 | |
|     method for the node first.
 | |
| 
 | |
|     For nodes that were part of a collection of statements (that applies to all
 | |
|     statement nodes), the visitor may also return a list of nodes rather than
 | |
|     just a single node.
 | |
| 
 | |
|     Usually you use the transformer like this::
 | |
| 
 | |
|        node = YourTransformer().visit(node)
 | |
|     """
 | |
| 
 | |
|     def generic_visit(self, node):
 | |
|         for field, old_value in iter_fields(node):
 | |
|             if isinstance(old_value, list):
 | |
|                 new_values = []
 | |
|                 for value in old_value:
 | |
|                     if isinstance(value, AST):
 | |
|                         value = self.visit(value)
 | |
|                         if value is None:
 | |
|                             continue
 | |
|                         elif not isinstance(value, AST):
 | |
|                             new_values.extend(value)
 | |
|                             continue
 | |
|                     new_values.append(value)
 | |
|                 old_value[:] = new_values
 | |
|             elif isinstance(old_value, AST):
 | |
|                 new_node = self.visit(old_value)
 | |
|                 if new_node is None:
 | |
|                     delattr(node, field)
 | |
|                 else:
 | |
|                     setattr(node, field, new_node)
 | |
|         return node
 | |
| 
 | |
| class slice(AST):
 | |
|     """Deprecated AST node class."""
 | |
| 
 | |
| class Index(slice):
 | |
|     """Deprecated AST node class. Use the index value directly instead."""
 | |
|     def __new__(cls, value, **kwargs):
 | |
|         return value
 | |
| 
 | |
| class ExtSlice(slice):
 | |
|     """Deprecated AST node class. Use ast.Tuple instead."""
 | |
|     def __new__(cls, dims=(), **kwargs):
 | |
|         return Tuple(list(dims), Load(), **kwargs)
 | |
| 
 | |
| # If the ast module is loaded more than once, only add deprecated methods once
 | |
| if not hasattr(Tuple, 'dims'):
 | |
|     # The following code is for backward compatibility.
 | |
|     # It will be removed in future.
 | |
| 
 | |
|     def _dims_getter(self):
 | |
|         """Deprecated. Use elts instead."""
 | |
|         return self.elts
 | |
| 
 | |
|     def _dims_setter(self, value):
 | |
|         self.elts = value
 | |
| 
 | |
|     Tuple.dims = property(_dims_getter, _dims_setter)
 | |
| 
 | |
| class Suite(mod):
 | |
|     """Deprecated AST node class.  Unused in Python 3."""
 | |
| 
 | |
| class AugLoad(expr_context):
 | |
|     """Deprecated AST node class.  Unused in Python 3."""
 | |
| 
 | |
| class AugStore(expr_context):
 | |
|     """Deprecated AST node class.  Unused in Python 3."""
 | |
| 
 | |
| class Param(expr_context):
 | |
|     """Deprecated AST node class.  Unused in Python 3."""
 | |
| 
 | |
| 
 | |
| def unparse(ast_obj):
 | |
|     global _Unparser
 | |
|     try:
 | |
|         unparser = _Unparser()
 | |
|     except NameError:
 | |
|         from _ast_unparse import Unparser as _Unparser
 | |
|         unparser = _Unparser()
 | |
|     return unparser.visit(ast_obj)
 | |
| 
 | |
| 
 | |
| def main(args=None):
 | |
|     import argparse
 | |
|     import sys
 | |
| 
 | |
|     parser = argparse.ArgumentParser(color=True)
 | |
|     parser.add_argument('infile', nargs='?', default='-',
 | |
|                         help='the file to parse; defaults to stdin')
 | |
|     parser.add_argument('-m', '--mode', default='exec',
 | |
|                         choices=('exec', 'single', 'eval', 'func_type'),
 | |
|                         help='specify what kind of code must be parsed')
 | |
|     parser.add_argument('--no-type-comments', default=True, action='store_false',
 | |
|                         help="don't add information about type comments")
 | |
|     parser.add_argument('-a', '--include-attributes', action='store_true',
 | |
|                         help='include attributes such as line numbers and '
 | |
|                              'column offsets')
 | |
|     parser.add_argument('-i', '--indent', type=int, default=3,
 | |
|                         help='indentation of nodes (number of spaces)')
 | |
|     parser.add_argument('--feature-version',
 | |
|                         type=str, default=None, metavar='VERSION',
 | |
|                         help='Python version in the format 3.x '
 | |
|                              '(for example, 3.10)')
 | |
|     parser.add_argument('-O', '--optimize',
 | |
|                         type=int, default=-1, metavar='LEVEL',
 | |
|                         help='optimization level for parser (default -1)')
 | |
|     parser.add_argument('--show-empty', default=False, action='store_true',
 | |
|                         help='show empty lists and fields in dump output')
 | |
|     args = parser.parse_args(args)
 | |
| 
 | |
|     if args.infile == '-':
 | |
|         name = '<stdin>'
 | |
|         source = sys.stdin.buffer.read()
 | |
|     else:
 | |
|         name = args.infile
 | |
|         with open(args.infile, 'rb') as infile:
 | |
|             source = infile.read()
 | |
| 
 | |
|     # Process feature_version
 | |
|     feature_version = None
 | |
|     if args.feature_version:
 | |
|         try:
 | |
|             major, minor = map(int, args.feature_version.split('.', 1))
 | |
|         except ValueError:
 | |
|             parser.error('Invalid format for --feature-version; '
 | |
|                          'expected format 3.x (for example, 3.10)')
 | |
| 
 | |
|         feature_version = (major, minor)
 | |
| 
 | |
|     tree = parse(source, name, args.mode, type_comments=args.no_type_comments,
 | |
|                  feature_version=feature_version, optimize=args.optimize)
 | |
|     print(dump(tree, include_attributes=args.include_attributes,
 | |
|                indent=args.indent, show_empty=args.show_empty))
 | |
| 
 | |
| if __name__ == '__main__':
 | |
|     main()
 |