From 7165a4f1e474d68e20c8ec812ca59eb1a38e1b03 Mon Sep 17 00:00:00 2001
From: jfbu <jfbu@free.fr>
Date: Sat, 27 May 2017 16:47:31 +0200
Subject: [PATCH] Fix #3788: Docutils emits warnings for unsupported languages

This monkey-patches docutils.languages.get_language() to suppress
Docutils emitted warning when the document settings use a language_code
for which Docutils has no ready-made localisation. The language_code is
needed for functioning of the smartquotes transform.
---
 CHANGES                        |  1 +
 sphinx/application.py          | 10 ++++++++++
 sphinx/environment/__init__.py | 16 ++++++++++------
 3 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/CHANGES b/CHANGES
index d85606bcc..b8dd5169a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -34,6 +34,7 @@ Bugs fixed
 * #3796: env.resolve_references() crashes when non-document node given
 * #3803: Sphinx crashes with invalid PO files
 * #3791: PDF "continued on next page" for long tables isn't internationalized
+* #3788: smartquotes emits warnings for unsupported languages
 
 Testing
 --------
diff --git a/sphinx/application.py b/sphinx/application.py
index 075f828fb..ba5aa2ca2 100644
--- a/sphinx/application.py
+++ b/sphinx/application.py
@@ -22,7 +22,9 @@ from collections import deque
 from six import iteritems
 from six.moves import cStringIO
 
+import docutils
 from docutils import nodes
+from docutils.languages import get_language as docutils_get_language
 from docutils.parsers.rst import directives, roles
 
 import sphinx
@@ -106,6 +108,14 @@ ENV_PICKLE_FILENAME = 'environment.pickle'
 logger = logging.getLogger(__name__)
 
 
+# monkey patch docutils get_language
+def patched_docutils_get_language(language_code, reporter=None):  # NOQA
+    return docutils_get_language(language_code)
+
+
+docutils.languages.get_language = patched_docutils_get_language
+
+
 class Sphinx(object):
 
     def __init__(self, srcdir, confdir, outdir, doctreedir, buildername,
diff --git a/sphinx/environment/__init__.py b/sphinx/environment/__init__.py
index 8aefa64f9..dbade8d4e 100644
--- a/sphinx/environment/__init__.py
+++ b/sphinx/environment/__init__.py
@@ -25,7 +25,7 @@ from six.moves import cPickle as pickle
 
 from docutils.io import NullOutput
 from docutils.core import Publisher
-from docutils.utils import Reporter, get_source_line
+from docutils.utils import Reporter, get_source_line, normalize_language_tag
 from docutils.utils.smartquotes import smartchars
 from docutils.parsers.rst import roles
 from docutils.parsers.rst.languages import en as english
@@ -672,18 +672,22 @@ class BuildEnvironment(object):
         self.settings['trim_footnote_reference_space'] = \
             self.config.trim_footnote_reference_space
         self.settings['gettext_compact'] = self.config.gettext_compact
-        language = (self.config.language or 'en').replace('_', '-')
+
+        language = self.config.language or 'en'
         self.settings['language_code'] = language
+        self.settings['smart_quotes'] = True
         if self.config.html_use_smartypants is not None:
             warnings.warn("html_use_smartypants option is deprecated. Smart "
                           "quotes are on by default; if you want to disable "
                           "or customize them, use the smart_quotes option in "
                           "docutils.conf.",
                           RemovedInSphinx17Warning)
-            if language in smartchars.quotes:
-                self.settings['smart_quotes'] = self.config.html_use_smartypants
-        elif language in smartchars.quotes:  # We enable smartypants by default
-            self.settings['smart_quotes'] = True
+            self.settings['smart_quotes'] = self.config.html_use_smartypants
+        for tag in normalize_language_tag(language):
+            if tag in smartchars.quotes:
+                    break
+        else:
+            self.settings['smart_quotes'] = False
 
         docutilsconf = path.join(self.srcdir, 'docutils.conf')
         # read docutils.conf from source dir, not from current dir