bug#24809: 25.1; Python.el improper indention after backslash-assignment-continuation

[npostavs]

From: Jules Tamagnan <jtamagnan@gmail.com>

> an_overly_long_variable_name = 
> some_object.some_method(some_argument_to_some_method)
>
> could be split like this:
>
> an_overly_long_variable_name = (
>     some_object.some_method(some_argument_to_some_method))
>
> or if someone wanted to use a backslash like this:
>
> an_overly_long_variable_name = \
>     some_object.some_method(some_argument_to_some_method)
>
> instead of like:
>
> an_overly_long_variable_name = \
>                                
> some_object.some_method(some_argument_to_some_method)
> ----------

Ah, I'd been looking at stuff from the test suite which looked like:

    an_overly_long_variable_name = something \
                                   another.thing(etc)

which seems a bit neater than

    an_overly_long_variable_name = something \
        another.thing(etc)

but I find your example convincing.  And we still have parens if the
first kind of indentation is preferred:

    an_overly_long_variable_name = (something 
                                    another.thing(etc))

I actually have the fix for the tests already written anyway.  I'll wait
a week or so before pushing, in case anyone else has some comments on
this.

>From 5476e881e1d302bcd40a407de0946d383012384f Mon Sep 17 00:00:00 2001
From: Jules Tamagnan <jtamagnan@gmail.com>
Date: Thu, 27 Oct 2016 15:03:31 -0700
Subject: [PATCH v2 1/3] Comply with pep 8 style guide for backslash in
 assignment (Bug#24809)

* lisp/progmodes/python.el (python-indent--calculate-indentation):
Increase indent by `python-indent-offset' after
`:after-backslash-assignment-continuation'.

Copyright-paperwork-exempt: yes
---
 lisp/progmodes/python.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 9cebc81bfc..02a2e4046d 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -1054,13 +1054,13 @@ (defun python-indent--calculate-indentation ()
            (max line-indentation base-indent)))
         (`(,(or :after-block-start
                 :after-backslash-first-line
+                :after-backslash-assignment-continuation
                 :inside-paren-newline-start) . ,start)
          ;; Add one indentation level.
          (goto-char start)
          (+ (current-indentation) python-indent-offset))
         (`(,(or :inside-paren
                 :after-backslash-block-continuation
-                :after-backslash-assignment-continuation
                 :after-backslash-dotted-continuation) . ,start)
          ;; Use the column given by the context.
          (goto-char start)
-- 
2.11.1

>From e931c8bd772be41dc4b98bc2614eacff529af195 Mon Sep 17 00:00:00 2001
From: Noam Postavsky <npostavs@gmail.com>
Date: Mon, 22 May 2017 12:32:04 -0400
Subject: [PATCH v2 2/3] ; Update test for previous change

* test/lisp/progmodes/python-tests.el
(python-indent-after-backslash-4): Indent after backslash is now
python-indent-offset.
---
 test/lisp/progmodes/python-tests.el | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/lisp/progmodes/python-tests.el 
b/test/lisp/progmodes/python-tests.el
index cd05710000..cea597acea 100644
--- a/test/lisp/progmodes/python-tests.el
+++ b/test/lisp/progmodes/python-tests.el
@@ -753,8 +753,8 @@ (ert-deftest python-indent-after-backslash-4 ()
   (python-tests-with-temp-buffer
    "
 super_awful_assignment = some_calculation() and \\\\
-                         another_calculation() and \\\\
-                         some_final_calculation()
+    another_calculation() and \\\\
+    some_final_calculation()
 "
    (python-tests-look-at
     "super_awful_assignment = some_calculation() and \\\\")
@@ -763,10 +763,10 @@ (ert-deftest python-indent-after-backslash-4 ()
    (python-tests-look-at "another_calculation() and \\\\")
    (should (eq (car (python-indent-context))
                :after-backslash-assignment-continuation))
-   (should (= (python-indent-calculate-indentation) 25))
+   (should (= (python-indent-calculate-indentation) python-indent-offset))
    (python-tests-look-at "some_final_calculation()")
    (should (eq (car (python-indent-context)) :after-backslash))
-   (should (= (python-indent-calculate-indentation) 25))))
+   (should (= (python-indent-calculate-indentation) python-indent-offset))))
 
 (ert-deftest python-indent-after-backslash-5 ()
   "Dotted continuation bizarre example."
-- 
2.11.1

v2-0003-Fix-backslashes-in-python-tests.patch
Description: patch