Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/jedi/api/refactoring/extract.py

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2020-11-12 16:05:57 +00:00
from textwrap import dedent
from parso import split_lines
from jedi import debug
from jedi.api.exceptions import RefactoringError
from jedi.api.refactoring import Refactoring, EXPRESSION_PARTS
from jedi.common import indent_block
from jedi.parser_utils import function_is_classmethod, function_is_staticmethod
_DEFINITION_SCOPES = ('suite', 'file_input')
_VARIABLE_EXCTRACTABLE = EXPRESSION_PARTS + \
('atom testlist_star_expr testlist test lambdef lambdef_nocond '
'keyword name number string fstring').split()
def extract_variable(inference_state, path, module_node, name, pos, until_pos):
nodes = _find_nodes(module_node, pos, until_pos)
debug.dbg('Extracting nodes: %s', nodes)
is_expression, message = _is_expression_with_error(nodes)
if not is_expression:
raise RefactoringError(message)
generated_code = name + ' = ' + _expression_nodes_to_string(nodes)
file_to_node_changes = {path: _replace(nodes, name, generated_code, pos)}
return Refactoring(inference_state, file_to_node_changes)
def _is_expression_with_error(nodes):
"""
Returns a tuple (is_expression, error_string).
"""
if any(node.type == 'name' and node.is_definition() for node in nodes):
return False, 'Cannot extract a name that defines something'
if nodes[0].type not in _VARIABLE_EXCTRACTABLE:
return False, 'Cannot extract a "%s"' % nodes[0].type
return True, ''
def _find_nodes(module_node, pos, until_pos):
"""
Looks up a module and tries to find the appropriate amount of nodes that
are in there.
"""
start_node = module_node.get_leaf_for_position(pos, include_prefixes=True)
if until_pos is None:
if start_node.type == 'operator':
next_leaf = start_node.get_next_leaf()
if next_leaf is not None and next_leaf.start_pos == pos:
start_node = next_leaf
if _is_not_extractable_syntax(start_node):
start_node = start_node.parent
if start_node.parent.type == 'trailer':
start_node = start_node.parent.parent
while start_node.parent.type in EXPRESSION_PARTS:
start_node = start_node.parent
nodes = [start_node]
else:
# Get the next leaf if we are at the end of a leaf
if start_node.end_pos == pos:
next_leaf = start_node.get_next_leaf()
if next_leaf is not None:
start_node = next_leaf
# Some syntax is not exactable, just use its parent
if _is_not_extractable_syntax(start_node):
start_node = start_node.parent
# Find the end
end_leaf = module_node.get_leaf_for_position(until_pos, include_prefixes=True)
if end_leaf.start_pos > until_pos:
end_leaf = end_leaf.get_previous_leaf()
if end_leaf is None:
raise RefactoringError('Cannot extract anything from that')
parent_node = start_node
while parent_node.end_pos < end_leaf.end_pos:
parent_node = parent_node.parent
nodes = _remove_unwanted_expression_nodes(parent_node, pos, until_pos)
# If the user marks just a return statement, we return the expression
# instead of the whole statement, because the user obviously wants to
# extract that part.
if len(nodes) == 1 and start_node.type in ('return_stmt', 'yield_expr'):
return [nodes[0].children[1]]
return nodes
def _replace(nodes, expression_replacement, extracted, pos,
insert_before_leaf=None, remaining_prefix=None):
# Now try to replace the nodes found with a variable and move the code
# before the current statement.
definition = _get_parent_definition(nodes[0])
if insert_before_leaf is None:
insert_before_leaf = definition.get_first_leaf()
first_node_leaf = nodes[0].get_first_leaf()
lines = split_lines(insert_before_leaf.prefix, keepends=True)
if first_node_leaf is insert_before_leaf:
if remaining_prefix is not None:
# The remaining prefix has already been calculated.
lines[:-1] = remaining_prefix
lines[-1:-1] = [indent_block(extracted, lines[-1]) + '\n']
extracted_prefix = ''.join(lines)
replacement_dct = {}
if first_node_leaf is insert_before_leaf:
replacement_dct[nodes[0]] = extracted_prefix + expression_replacement
else:
if remaining_prefix is None:
p = first_node_leaf.prefix
else:
p = remaining_prefix + _get_indentation(nodes[0])
replacement_dct[nodes[0]] = p + expression_replacement
replacement_dct[insert_before_leaf] = extracted_prefix + insert_before_leaf.value
for node in nodes[1:]:
replacement_dct[node] = ''
return replacement_dct
def _expression_nodes_to_string(nodes):
return ''.join(n.get_code(include_prefix=i != 0) for i, n in enumerate(nodes))
def _suite_nodes_to_string(nodes, pos):
n = nodes[0]
prefix, part_of_code = _split_prefix_at(n.get_first_leaf(), pos[0] - 1)
code = part_of_code + n.get_code(include_prefix=False) \
+ ''.join(n.get_code() for n in nodes[1:])
return prefix, code
def _split_prefix_at(leaf, until_line):
"""
Returns a tuple of the leaf's prefix, split at the until_line
position.
"""
# second means the second returned part
second_line_count = leaf.start_pos[0] - until_line
lines = split_lines(leaf.prefix, keepends=True)
return ''.join(lines[:-second_line_count]), ''.join(lines[-second_line_count:])
def _get_indentation(node):
return split_lines(node.get_first_leaf().prefix)[-1]
def _get_parent_definition(node):
"""
Returns the statement where a node is defined.
"""
while node is not None:
if node.parent.type in _DEFINITION_SCOPES:
return node
node = node.parent
raise NotImplementedError('We should never even get here')
def _remove_unwanted_expression_nodes(parent_node, pos, until_pos):
"""
This function makes it so for `1 * 2 + 3` you can extract `2 + 3`, even
though it is not part of the expression.
"""
typ = parent_node.type
is_suite_part = typ in ('suite', 'file_input')
if typ in EXPRESSION_PARTS or is_suite_part:
nodes = parent_node.children
for i, n in enumerate(nodes):
if n.end_pos > pos:
start_index = i
if n.type == 'operator':
start_index -= 1
break
for i, n in reversed(list(enumerate(nodes))):
if n.start_pos < until_pos:
end_index = i
if n.type == 'operator':
end_index += 1
# Something like `not foo or bar` should not be cut after not
for n2 in nodes[i:]:
if _is_not_extractable_syntax(n2):
end_index += 1
else:
break
break
nodes = nodes[start_index:end_index + 1]
if not is_suite_part:
nodes[0:1] = _remove_unwanted_expression_nodes(nodes[0], pos, until_pos)
nodes[-1:] = _remove_unwanted_expression_nodes(nodes[-1], pos, until_pos)
return nodes
return [parent_node]
def _is_not_extractable_syntax(node):
return node.type == 'operator' \
or node.type == 'keyword' and node.value not in ('None', 'True', 'False')
def extract_function(inference_state, path, module_context, name, pos, until_pos):
nodes = _find_nodes(module_context.tree_node, pos, until_pos)
assert len(nodes)
is_expression, _ = _is_expression_with_error(nodes)
context = module_context.create_context(nodes[0])
is_bound_method = context.is_bound_method()
params, return_variables = list(_find_inputs_and_outputs(module_context, context, nodes))
# Find variables
# Is a class method / method
if context.is_module():
insert_before_leaf = None # Leaf will be determined later
else:
node = _get_code_insertion_node(context.tree_node, is_bound_method)
insert_before_leaf = node.get_first_leaf()
if is_expression:
code_block = 'return ' + _expression_nodes_to_string(nodes) + '\n'
remaining_prefix = None
has_ending_return_stmt = False
else:
has_ending_return_stmt = _is_node_ending_return_stmt(nodes[-1])
if not has_ending_return_stmt:
# Find the actually used variables (of the defined ones). If none are
# used (e.g. if the range covers the whole function), return the last
# defined variable.
return_variables = list(_find_needed_output_variables(
context,
nodes[0].parent,
nodes[-1].end_pos,
return_variables
)) or [return_variables[-1]] if return_variables else []
remaining_prefix, code_block = _suite_nodes_to_string(nodes, pos)
after_leaf = nodes[-1].get_next_leaf()
first, second = _split_prefix_at(after_leaf, until_pos[0])
code_block += first
code_block = dedent(code_block)
if not has_ending_return_stmt:
output_var_str = ', '.join(return_variables)
code_block += 'return ' + output_var_str + '\n'
# Check if we have to raise RefactoringError
_check_for_non_extractables(nodes[:-1] if has_ending_return_stmt else nodes)
decorator = ''
self_param = None
if is_bound_method:
if not function_is_staticmethod(context.tree_node):
function_param_names = context.get_value().get_param_names()
if len(function_param_names):
self_param = function_param_names[0].string_name
params = [p for p in params if p != self_param]
if function_is_classmethod(context.tree_node):
decorator = '@classmethod\n'
else:
code_block += '\n'
function_code = '%sdef %s(%s):\n%s' % (
decorator,
name,
', '.join(params if self_param is None else [self_param] + params),
indent_block(code_block)
)
function_call = '%s(%s)' % (
('' if self_param is None else self_param + '.') + name,
', '.join(params)
)
if is_expression:
replacement = function_call
else:
if has_ending_return_stmt:
replacement = 'return ' + function_call + '\n'
else:
replacement = output_var_str + ' = ' + function_call + '\n'
replacement_dct = _replace(nodes, replacement, function_code, pos,
insert_before_leaf, remaining_prefix)
if not is_expression:
replacement_dct[after_leaf] = second + after_leaf.value
file_to_node_changes = {path: replacement_dct}
return Refactoring(inference_state, file_to_node_changes)
def _check_for_non_extractables(nodes):
for n in nodes:
try:
children = n.children
except AttributeError:
if n.value == 'return':
raise RefactoringError(
'Can only extract return statements if they are at the end.')
if n.value == 'yield':
raise RefactoringError('Cannot extract yield statements.')
else:
_check_for_non_extractables(children)
def _is_name_input(module_context, names, first, last):
for name in names:
if name.api_type == 'param' or not name.parent_context.is_module():
if name.get_root_context() is not module_context:
return True
if name.start_pos is None or not (first <= name.start_pos < last):
return True
return False
def _find_inputs_and_outputs(module_context, context, nodes):
first = nodes[0].start_pos
last = nodes[-1].end_pos
inputs = []
outputs = []
for name in _find_non_global_names(nodes):
if name.is_definition():
if name not in outputs:
outputs.append(name.value)
else:
if name.value not in inputs:
name_definitions = context.goto(name, name.start_pos)
if not name_definitions \
or _is_name_input(module_context, name_definitions, first, last):
inputs.append(name.value)
# Check if outputs are really needed:
return inputs, outputs
def _find_non_global_names(nodes):
for node in nodes:
try:
children = node.children
except AttributeError:
if node.type == 'name':
yield node
else:
# We only want to check foo in foo.bar
if node.type == 'trailer' and node.children[0] == '.':
continue
for x in _find_non_global_names(children): # Python 2...
yield x
def _get_code_insertion_node(node, is_bound_method):
if not is_bound_method or function_is_staticmethod(node):
while node.parent.type != 'file_input':
node = node.parent
while node.parent.type in ('async_funcdef', 'decorated', 'async_stmt'):
node = node.parent
return node
def _find_needed_output_variables(context, search_node, at_least_pos, return_variables):
"""
Searches everything after at_least_pos in a node and checks if any of the
return_variables are used in there and returns those.
"""
for node in search_node.children:
if node.start_pos < at_least_pos:
continue
return_variables = set(return_variables)
for name in _find_non_global_names([node]):
if not name.is_definition() and name.value in return_variables:
return_variables.remove(name.value)
yield name.value
def _is_node_ending_return_stmt(node):
t = node.type
if t == 'simple_stmt':
return _is_node_ending_return_stmt(node.children[0])
return t == 'return_stmt'