scikit-learn/doc/sphinxext/sphinx_gallery/py_source_parser.py

100 lines
3.3 KiB
Python

# -*- coding: utf-8 -*-
r"""
Parser for python source files
==============================
"""
# Created Sun Nov 27 14:03:07 2016
# Author: Óscar Nájera
from __future__ import division, absolute_import, print_function
import ast
import re
from textwrap import dedent
SYNTAX_ERROR_DOCSTRING = """
SyntaxError
===========
Example script with invalid Python syntax
"""
def get_docstring_and_rest(filename):
"""Separate `filename` content between docstring and the rest
Strongly inspired from ast.get_docstring.
Returns
-------
docstring: str
docstring of `filename`
rest: str
`filename` content without the docstring
"""
# can't use codecs.open(filename, 'r', 'utf-8') here b/c ast doesn't
# seem to work with unicode strings in Python2.7
# "SyntaxError: encoding declaration in Unicode string"
with open(filename, 'rb') as fid:
content = fid.read()
# change from Windows format to UNIX for uniformity
content = content.replace(b'\r\n', b'\n')
try:
node = ast.parse(content)
except SyntaxError:
return SYNTAX_ERROR_DOCSTRING, content.decode('utf-8')
if not isinstance(node, ast.Module):
raise TypeError("This function only supports modules. "
"You provided {0}".format(node.__class__.__name__))
if node.body and isinstance(node.body[0], ast.Expr) and \
isinstance(node.body[0].value, ast.Str):
docstring_node = node.body[0]
docstring = docstring_node.value.s
if hasattr(docstring, 'decode'): # python2.7
docstring = docstring.decode('utf-8')
# This get the content of the file after the docstring last line
# Note: 'maxsplit' argument is not a keyword argument in python2
rest = content.decode('utf-8').split('\n', docstring_node.lineno)[-1]
return docstring, rest
else:
raise ValueError(('Could not find docstring in file "{0}". '
'A docstring is required by sphinx-gallery')
.format(filename))
def split_code_and_text_blocks(source_file):
"""Return list with source file separated into code and text blocks.
Returns
-------
blocks : list of (label, content)
List where each element is a tuple with the label ('text' or 'code'),
and content string of block.
"""
docstring, rest_of_content = get_docstring_and_rest(source_file)
blocks = [('text', docstring)]
pattern = re.compile(
r'(?P<header_line>^#{20,}.*)\s(?P<text_content>(?:^#.*\s)*)',
flags=re.M)
pos_so_far = 0
for match in re.finditer(pattern, rest_of_content):
match_start_pos, match_end_pos = match.span()
code_block_content = rest_of_content[pos_so_far:match_start_pos]
text_content = match.group('text_content')
sub_pat = re.compile('^#', flags=re.M)
text_block_content = dedent(re.sub(sub_pat, '', text_content)).lstrip()
if code_block_content.strip():
blocks.append(('code', code_block_content))
if text_block_content.strip():
blocks.append(('text', text_block_content))
pos_so_far = match_end_pos
remaining_content = rest_of_content[pos_so_far:]
if remaining_content.strip():
blocks.append(('code', remaining_content))
return blocks