bug#58023: 29.0.50; end-of-defun in python-mode does not work with nested function with multi-line arguments

[kobarity]

Hi,

The following steps will place the point at the end of the class C,
not the end of the method a.

1. emacs -Q
2. Load the following Python file using M-x find-file

#+begin_src python
class C:
    def a(self
          ):
        pass

    def b(self):
        pass
#+end_src

3. C-n (M-x forward-line)
4. C-M-e (M-x end-of-defun)

This happens when the method (nested function) has multi-line
arguments.

This is caused by the wrong behavior of
`python-nav-beginning-of-defun'.  When the point is inside of the
parens of the nested function, it fails to detect the beginning of the
nested function and moves the point to the beginning of the outer
class/function.

The root cause of this problem exists in
`python-info-looking-at-beginning-of-defun'.  It checks syntax context
to detect correct keywords, but it checks at the current position
although keywords are searched for at the beginning of the line.  If
the point is inside of the parens of the function definition, syntax
context is "paren" and `python-info-looking-at-beginning-of-defun'
returns nil, which is not expected.  The syntax context should be
checked after moving the point to the beginning of the line.

Attached is a patch to fix this issue.

Best Regards,

--

In GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo
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Repository branch: master
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0001-Fix-syntax-check-in-python-info-looking-at-beginning.patch
Description: Binary data