"""

Docstrings are another source of information for functions and classes.

:mod:`jedi.evaluate.dynamic` tries to find all executions of functions, while

the docstring parsing is much easier. There are two different types of

docstrings that |jedi| understands:

- `Sphinx <http://sphinx-doc.org/markup/desc.html#info-field-lists>`_

- `Epydoc <http://epydoc.sourceforge.net/manual-fields.html>`_

For example, the sphinx annotation ``:type foo: str`` clearly states that the

type of ``foo`` is ``str``.

As an addition to parameter searching, this module also provides return

annotations.

"""

from ast import literal_eval

import re

from itertools import chain

from textwrap import dedent

from jedi.evaluate.cache import memoize_default

from jedi.parser import Parser, load_grammar

from jedi.common import indent_block

from jedi.evaluate.iterable import Array, FakeSequence, AlreadyEvaluated

DOCSTRING_PARAM_PATTERNS = [

r'\s*:type\s+%s:\s*([^\n]+)', # Sphinx

r'\s*:param\s+(\w+)\s+%s:[^\n]+', # Sphinx param with type

r'\s*@type\s+%s:\s*([^\n]+)', # Epydoc

]

DOCSTRING_RETURN_PATTERNS = [

re.compile(r'\s*:rtype:\s*([^\n]+)', re.M), # Sphinx

re.compile(r'\s*@rtype:\s*([^\n]+)', re.M), # Epydoc

]

REST_ROLE_PATTERN = re.compile(r':[^`]+:`([^`]+)`')

try:

from numpydoc.docscrape import NumpyDocString

except ImportError:

def _search_param_in_numpydocstr(docstr, param_str):

return []

else:

def _search_param_in_numpydocstr(docstr, param_str):

"""Search `docstr` (in numpydoc format) for type(-s) of `param_str`."""

params = NumpyDocString(docstr)._parsed_data['Parameters']

for p_name, p_type, p_descr in params:

if p_name == param_str:

m = re.match('([^,]+(,[^,]+)*?)(,[ ]*optional)?$', p_type)

if m:

p_type = m.group(1)

if p_type.startswith('{'):

types = set(type(x).__name__ for x in literal_eval(p_type))

return list(types)

else:

return [p_type]

return []

def _search_param_in_docstr(docstr, param_str):

"""

Search `docstr` for type(-s) of `param_str`.

>>> _search_param_in_docstr(':type param: int', 'param')

['int']

>>> _search_param_in_docstr('@type param: int', 'param')

['int']

>>> _search_param_in_docstr(

... ':type param: :class:`threading.Thread`', 'param')

['threading.Thread']

>>> bool(_search_param_in_docstr('no document', 'param'))

False

>>> _search_param_in_docstr(':param int param: some description', 'param')

['int']

"""

# look at #40 to see definitions of those params

patterns = [re.compile(p % re.escape(param_str))

for p in DOCSTRING_PARAM_PATTERNS]

for pattern in patterns:

match = pattern.search(docstr)

if match:

return [_strip_rst_role(match.group(1))]

return (_search_param_in_numpydocstr(docstr, param_str) or

[])

def _strip_rst_role(type_str):

"""

Strip off the part looks like a ReST role in `type_str`.

>>> _strip_rst_role(':class:`ClassName`') # strip off :class:

'ClassName'

>>> _strip_rst_role(':py:obj:`module.Object`') # works with domain

'module.Object'

>>> _strip_rst_role('ClassName') # do nothing when not ReST role

'ClassName'

See also:

http://sphinx-doc.org/domains.html#cross-referencing-python-objects

"""

match = REST_ROLE_PATTERN.match(type_str)

if match:

return match.group(1)

else:

return type_str

def _evaluate_for_statement_string(evaluator, string, module):

code = dedent("""

def pseudo_docstring_stuff():

# Create a pseudo function for docstring statements.

%s

""")

if string is None:

return []

for element in re.findall('((?:\w+\.)*\w+)\.', string):

# Try to import module part in dotted name.

# (e.g., 'threading' in 'threading.Thread').

string = 'import %s\n' % element + string

# Take the default grammar here, if we load the Python 2.7 grammar here, it

# will be impossible to use `...` (Ellipsis) as a token. Docstring types

# don't need to conform with the current grammar.

p = Parser(load_grammar(), code % indent_block(string))

try:

pseudo_cls = p.module.subscopes[0]

# First pick suite, then simple_stmt (-2 for DEDENT) and then the node,

# which is also not the last item, because there's a newline.

stmt = pseudo_cls.children[-1].children[-2].children[-2]

except (AttributeError, IndexError):

return []

# Use the module of the param.

# TODO this module is not the module of the param in case of a function

# call. In that case it's the module of the function call.

# stuffed with content from a function call.

pseudo_cls.parent = module

return list(_execute_types_in_stmt(evaluator, stmt))

def _execute_types_in_stmt(evaluator, stmt):

"""

Executing all types or general elements that we find in a statement. This

doesn't include tuple, list and dict literals, because the stuff they

contain is executed. (Used as type information).

"""

definitions = evaluator.eval_element(stmt)

return chain.from_iterable(_execute_array_values(evaluator, d) for d in definitions)

def _execute_array_values(evaluator, array):

"""

Tuples indicate that there's not just one return value, but the listed

ones. `(str, int)` means that it returns a tuple with both types.

"""

if isinstance(array, Array):

values = []

for typ in array.values():

objects = _execute_array_values(evaluator, typ)

values.append(AlreadyEvaluated(objects))

return [FakeSequence(evaluator, values, array.type)]

else:

return evaluator.execute(array)

@memoize_default(None, evaluator_is_first_arg=True)

def follow_param(evaluator, param):

func = param.parent_function

return [p

for param_str in _search_param_in_docstr(func.raw_doc,

str(param.name))

for p in _evaluate_for_statement_string(evaluator, param_str,

param.get_parent_until())]

@memoize_default(None, evaluator_is_first_arg=True)

def find_return_types(evaluator, func):

def search_return_in_docstr(code):

for p in DOCSTRING_RETURN_PATTERNS:

match = p.search(code)

if match:

return _strip_rst_role(match.group(1))

type_str = search_return_in_docstr(func.raw_doc)

return _evaluate_for_statement_string(evaluator, type_str, func.get_parent_until())