##// END OF EJS Templates
Fix error in completer when the cursor position is at the start of a...
Fix error in completer when the cursor position is at the start of a string.

File last commit:

r22963:2961b531
r23461:c39010d6
Show More
tokenutil.py
127 lines | 3.7 KiB | text/x-python | PythonLexer
"""Token-related utilities"""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
from collections import namedtuple
from io import StringIO
from keyword import iskeyword
from . import tokenize2
from .py3compat import cast_unicode_py2
Token = namedtuple('Token', ['token', 'text', 'start', 'end', 'line'])
def generate_tokens(readline):
"""wrap generate_tokens to catch EOF errors"""
try:
for token in tokenize2.generate_tokens(readline):
yield token
except tokenize2.TokenError:
# catch EOF error
return
def line_at_cursor(cell, cursor_pos=0):
"""Return the line in a cell at a given cursor position
Used for calling line-based APIs that don't support multi-line input, yet.
Parameters
----------
cell: str
multiline block of text
cursor_pos: integer
the cursor position
Returns
-------
(line, offset): (text, integer)
The line with the current cursor, and the character offset of the start of the line.
"""
offset = 0
lines = cell.splitlines(True)
for line in lines:
next_offset = offset + len(line)
if next_offset >= cursor_pos:
break
offset = next_offset
else:
line = ""
return (line, offset)
def token_at_cursor(cell, cursor_pos=0):
"""Get the token at a given cursor
Used for introspection.
Function calls are prioritized, so the token for the callable will be returned
if the cursor is anywhere inside the call.
Parameters
----------
cell : unicode
A block of Python code
cursor_pos : int
The location of the cursor in the block where the token should be found
"""
cell = cast_unicode_py2(cell)
names = []
tokens = []
call_names = []
offsets = {1: 0} # lines start at 1
for tup in generate_tokens(StringIO(cell).readline):
tok = Token(*tup)
# token, text, start, end, line = tup
start_line, start_col = tok.start
end_line, end_col = tok.end
if end_line + 1 not in offsets:
# keep track of offsets for each line
lines = tok.line.splitlines(True)
for lineno, line in zip(range(start_line + 1, end_line + 2), lines):
if lineno not in offsets:
offsets[lineno] = offsets[lineno-1] + len(line)
offset = offsets[start_line]
# allow '|foo' to find 'foo' at the beginning of a line
boundary = cursor_pos + 1 if start_col == 0 else cursor_pos
if offset + start_col >= boundary:
# current token starts after the cursor,
# don't consume it
break
if tok.token == tokenize2.NAME and not iskeyword(tok.text):
if names and tokens and tokens[-1].token == tokenize2.OP and tokens[-1].text == '.':
names[-1] = "%s.%s" % (names[-1], tok.text)
else:
names.append(tok.text)
elif tok.token == tokenize2.OP:
if tok.text == '=' and names:
# don't inspect the lhs of an assignment
names.pop(-1)
if tok.text == '(' and names:
# if we are inside a function call, inspect the function
call_names.append(names[-1])
elif tok.text == ')' and call_names:
call_names.pop(-1)
tokens.append(tok)
if offsets[end_line] + end_col > cursor_pos:
# we found the cursor, stop reading
break
if call_names:
return call_names[-1]
elif names:
return names[-1]
else:
return ''