bug#57262: 29.0.50; Python indentation problem of block continuation

bug#57262: 29.0.50; Python indentation problem of block continuation

[kobarity]

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Hi,

When you type the following code in the Python mode buffer and hit
Enter key, the next line will be indented with 4 spaces (assuming
`python-indent-offset' is 4).

#+begin_src python
for long_variable_name \
#+end_src

However, it is not appropriate because it will be "continuation line
with same indent as next logical line" error.  The indentation should
be one level deeper as follows:

#+begin_src python
for long_variable_name \
        in (1, 2):
    print(long_variable_name)
#+end_src

Attached is a patch to fix this issue.

Best Regards,

--

In GNU Emacs 29.0.50 (build 10, x86_64-pc-linux-gnu)
 of 2022-08-15 built on ubuntu
System Description: Ubuntu 22.04.1 LTS

Configured using:
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Major mode: Python

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[-- Attachment #2: fix-indentation.patch --]
[-- Type: application/octet-stream, Size: 2602 bytes --]

commit 2b4e87908837d2206396949421bc1da352ef720f
Author: kobarity <kobarity@gmail.com>
Date:   Wed Aug 17 23:03:45 2022 +0900

    Fix Python indentation of block continuation
    
    * lisp/progmodes/python.el (python-indent--calculate-indentation):
    Fix indentation of :after-backslash-block-continuation.
    
    * test/lisp/progmodes/python-tests.el
    (python-indent-after-backslash-6): New test.

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index e135039199..9a2d17abb4 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -1238,8 +1238,14 @@ python-indent--calculate-indentation
          ;; Add one indentation level.
          (goto-char start)
          (+ (current-indentation) python-indent-offset))
+        (`(:after-backslash-block-continuation . ,start)
+         (goto-char start)
+         (let ((column (current-column)))
+           (if (= column (+ (current-indentation) python-indent-offset))
+               ;; Add one level to avoid same indent as next logical line.
+               (+ column python-indent-offset)
+             column)))
         (`(,(or :inside-paren
-                :after-backslash-block-continuation
                 :after-backslash-dotted-continuation) . ,start)
          ;; Use the column given by the context.
          (goto-char start)
diff --git a/test/lisp/progmodes/python-tests.el b/test/lisp/progmodes/python-tests.el
index 875c92573e..0904dfc963 100644
--- a/test/lisp/progmodes/python-tests.el
+++ b/test/lisp/progmodes/python-tests.el
@@ -1250,6 +1250,25 @@ python-indent-after-backslash-5
                :after-backslash-dotted-continuation))
    (should (= (python-indent-calculate-indentation) 16))))
 
+(ert-deftest python-indent-after-backslash-6 ()
+  "Backslash continuation from for block."
+  (python-tests-with-temp-buffer
+   "
+for long_variable_name \\
+        in (1, 2):
+    print(long_variable_name)
+"
+   (python-tests-look-at "for long_variable_name \\")
+   (should (eq (car (python-indent-context)) :no-indent))
+   (should (= (python-indent-calculate-indentation) 0))
+   (python-tests-look-at "in (1, 2):")
+   (should (eq (car (python-indent-context))
+               :after-backslash-block-continuation))
+   (should (= (python-indent-calculate-indentation) 8))
+   (python-tests-look-at "print(long_variable_name)")
+   (should (eq (car (python-indent-context)) :after-block-start))
+   (should (= (python-indent-calculate-indentation) 4))))
+
 (ert-deftest python-indent-block-enders-1 ()
   "Test de-indentation for pass keyword."
   (python-tests-with-temp-buffer

bug#57262: 29.0.50; Python indentation problem of block continuation

[Lars Ingebrigtsen]

kobarity <kobarity@gmail.com> writes:

> Attached is a patch to fix this issue.

Thanks; pushed to Emacs 29.