From c2a396c776bf4dbc6c92e47808ab553ad262ec48 Mon Sep 17 00:00:00 2001
From: jfbu <jfbu@free.fr>
Date: Tue, 17 Jul 2018 23:54:53 +0200
Subject: [PATCH] LaTeX: for Cyrillic and with xindy, get Latin letter groups
 too

Refs: #5134
---
 sphinx/texinputs/Makefile_t            |  3 ++
 sphinx/texinputs/sphinx-basiclatin.xdy | 42 ++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 sphinx/texinputs/sphinx-basiclatin.xdy

diff --git a/sphinx/texinputs/Makefile_t b/sphinx/texinputs/Makefile_t
index 1ce4b1324..97054def0 100644
--- a/sphinx/texinputs/Makefile_t
+++ b/sphinx/texinputs/Makefile_t
@@ -27,6 +27,9 @@ export XINDYOPTS = {{ xindy_lang_option }} -M sphinx.xdy
 {% if latex_engine == 'pdflatex' and xindy_cyrillic -%}
 XINDYOPTS += -M cyrLICRutf8.xdy
 {% endif -%}
+{% if xindy_cyrillic -%}
+XINDYOPTS += -M sphinx-basiclatin.xdy
+{% endif -%}
 {% if latex_engine == 'xelatex' or latex_engine == 'lualatex' -%}
 XINDYOPTS += -I xelatex
 {% endif -%}
diff --git a/sphinx/texinputs/sphinx-basiclatin.xdy b/sphinx/texinputs/sphinx-basiclatin.xdy
new file mode 100644
index 000000000..f611ac5ca
--- /dev/null
+++ b/sphinx/texinputs/sphinx-basiclatin.xdy
@@ -0,0 +1,42 @@
+;; xindy style file to provide indexing of (ascii) Latin names
+;; in an otherwise non-Latin (i.e. Cyrillic) context.
+;; TODO: should we support also iso-latin-1 ?
+;; Contributed by the Sphinx team, July 2018.
+
+(define-letter-groups
+  ("A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M"
+   "N" "O" "P" "Q" "R" "S" "T" "U" "V" "W" "X" "Y" "Z"))
+
+(define-rule-set "latin-toupper"
+
+  :rules (("a" "A" :string :again)
+	  ("b" "B" :string :again)
+	  ("c" "C" :string :again)
+	  ("d" "D" :string :again)
+	  ("e" "E" :string :again)
+	  ("f" "F" :string :again)
+	  ("g" "G" :string :again)
+	  ("h" "H" :string :again)
+	  ("i" "I" :string :again)
+	  ("j" "J" :string :again)
+	  ("k" "K" :string :again)
+	  ("l" "L" :string :again)
+	  ("m" "M" :string :again)
+	  ("n" "N" :string :again)
+	  ("o" "O" :string :again)
+	  ("p" "P" :string :again)
+	  ("q" "Q" :string :again)
+	  ("r" "R" :string :again)
+	  ("s" "S" :string :again)
+	  ("t" "T" :string :again)
+	  ("u" "U" :string :again)
+	  ("v" "V" :string :again)
+	  ("w" "W" :string :again)
+	  ("x" "X" :string :again)
+	  ("y" "Y" :string :again)
+	  ("z" "Z" :string :again)
+	  ))
+
+(use-rule-set
+  :run 0
+  :rule-set ("latin-toupper"))