linetable 0.0.3

library to manage Python Locations Table (co_linetable)

About linetable

linetable is a library parse and generate co_linetable attributes in Python code objects.

Based on https://github.com/python/cpython/blob/main/Objects/locations.md

Installing

linetable can be installed from pypi:

pip install linetable

should just work for most of the users

Usage

Existing linetable can be parsed using linetable.parse_linetable:

>>> def testfunc():
...   x = 3
...   y = x + 1
...   return y

>>> list(linetable.parse_linetable(testfunc.__code__.co_linetable))
[
    (1, 1, 1, 0, 0),
    (1, 2, 2, 6, 7),
    (1, 2, 2, 2, 3),
    (1, 3, 3, 6, 7),
    (1, 3, 3, 10, 11),
    (2, 3, 3, 6, 11),
    (1, 3, 3, 2, 3),
    (1, 4, 4, 9, 10),
    (1, 4, 4, 2, 10),
]

If you prefer the output in the format of dis.Positions objects, you can create them from the yielded values:

>>> [dis.Positions(*e[1:]) for e in linetable.parse_linetable(testfunc.__code__.co_linetable)]
[Positions(lineno=1, end_lineno=1, col_offset=0, end_col_offset=0), Positions(lineno=2, end_lineno=2, col_offset=8, end_col_offset=9), Positions(lineno=2, end_lineno=2, col_offset=4, end_col_offset=5), Positions(lineno=3, end_lineno=3, col_offset=8, end_col_offset=9), Positions(lineno=3, end_lineno=3, col_offset=12, end_col_offset=13), Positions(lineno=3, end_lineno=3, col_offset=8, end_col_offset=13), Positions(lineno=3, end_lineno=3, col_offset=4, end_col_offset=5), Positions(lineno=4, end_lineno=4, col_offset=11, end_col_offset=12), Positions(lineno=4, end_lineno=4, col_offset=4, end_col_offset=12)]

If you have the linetable, you can generate back the binary encoded version using linetable.generate_linetable:

>>> lt = [
...     (1, 1, 1, 0, 0),
...     (1, 2, 2, 6, 7),
...     (1, 2, 2, 2, 3),
...     (1, 3, 3, 6, 7),
...     (1, 3, 3, 10, 11),
...     (2, 3, 3, 6, 11),
...     (1, 3, 3, 2, 3),
...     (1, 4, 4, 9, 10),
...     (1, 4, 4, 2, 10),
... ]
>>> linetable.generate_linetable(lt)
b"\x80\x00\xd8\x06\x07\x80!\xd8\x06\x07\x88!\x81e\x80!\xd8\t\n\x80("