docbuild: Japanese characters creeping into other parts of Sage documentation

[jhpalmieri]

Japanese characters creep into various parts of Sage documentation. For example, the table of contents in the (English) Sage developer's guide (html) has headings in Japanese, and when building the PDF version of it/a_tour_of_sage, I see this error:

    ! Package inputenc Error: Unicode character リ (U+30EA)

Indeed, the file local/share/doc/sage/latex/it/a_tour_of_sage/a_tour_of_sage.tex has the line

    \renewcommand{\releasename}{リリース}

and also a few lines earlier

    \date{2021年06月08日}

and at the bottom

    \renewcommand{\indexname}{索引}

These lines are the same as in ja/a_tour_of_sage/a_tour_of_sage.tex.

Depends on #31948

CC: @zlscherr @kiwifb @kliem @mkoeppe

Component: documentation

Issue created by migration from https://trac.sagemath.org/ticket/31936

[jhpalmieri]

Description changed:

--- 
+++ 
@@ -3,7 +3,7 @@
 ```
     ! Package inputenc Error: Unicode character リ (U+30EA)
 ```
-Indeed, the file `local/share/doc/sage/latex/it/a_tour_of_sage/a_tour_of_sage.tex has the line
+Indeed, the file `local/share/doc/sage/latex/it/a_tour_of_sage/a_tour_of_sage.tex` has the line
 
 ```
     \renewcommand{\releasename}{リリース}

[slel]

comment:2

Since maybe Sage 9.3, some interface elements of
the (English language) (html) developer guide appear
in Japanese for me in Sage built from source.

Comparing the online version and my local version
of the "Git setup" page for instance:

• https://doc.sagemath.org/html/en/developer/git_setup.html
• file:///path_to_sage/local/share/doc/sage/html/en/developer/git_setup.html

the correspondence is as follows.

Menu headers in the left menu:

• Table of Contents - 目次
• Previous topic - 前のトピックへ
• Next topic - 次のトピックへ
• This Page - このページ
• Quick search - クイック検索

Navigation menu (top right and bottom right):

• previous - 前へ
• next - 次へ
• index - 索引

[jhpalmieri]

Description changed:

--- 
+++ 
@@ -1,4 +1,4 @@
-When building it/a_tour_of_sage, I see this error:
+Japanese characters creep into various parts of Sage documentation. For example, the table of contents in the (English) Sage developer's guide (html) has headings in Japanese, and when building the PDF version of `it/a_tour_of_sage`, I see this error:
 
 ```
     ! Package inputenc Error: Unicode character リ (U+30EA)
@@ -8,7 +8,7 @@
 ```
     \renewcommand{\releasename}{リリース}
 ```
-Why does the Italian tour have these Japanese characters in it? A few lines earlier, I also see
+and also a few lines earlier
 
 ```
     \date{2021年06月08日}

[jhpalmieri]

comment:3

Oh, I see that too. Ticket summary changed.

[jhpalmieri]

comment:4

The Sphinx upgrade #31696 doesn't help.

[dimpase]

comment:5

I cannot reproduce this on (Gentoo) Linux. Everything looks fine.
On the other hand, I see it (Japanese menus) on macOS 11.4, too.

[dimpase]

comment:6

#30551 changed various locale settings, perhaps it's the culprit.

[jhpalmieri]

comment:7

The problem is #31344, in particular commit b4ceee5.