Add :confval:html_css_files

CHANGES

@@ -59,6 +59,7 @@ Features added
 * LaTeX: new key ``'fvset'`` for :confval:`latex_elements`. For
   XeLaTeX/LuaLaTeX its default sets ``fanvyvrb`` to use normal, not small,
   fontsize in code-blocks (refs: #4793)
+* Add :confval:`html_css_files` for adding CSS files from configuration
 
 Bugs fixed
 ----------

doc/config.rst

@@ -59,9 +59,6 @@ Important points to note:
   Note that the current builder tag is not available in ``conf.py``, as it is
   created *after* the builder is initialized.
 
-.. seealso:: Additional configurations, such as adding stylesheets,
-   javascripts, builders, etc. can be made through the :doc:`/extdev/appapi`.
-
 
 General configuration
 ---------------------
@@ -846,6 +843,22 @@ that use Sphinx's HTMLWriter class.
       The image file will be copied to the ``_static`` directory of the output
       HTML, but only if the file does not already exist there.
 
+.. confval:: html_css_files
+
+   A list of CSS files.  The entry must be a *filename* string or a tuple
+   containing the *filename* string and the *attributes* dictionary.  The
+   *filename* must be relative to the :confval:`html_static_path`, or a full URI
+   with scheme like ``http://example.org/style.css``.  The *attributes* is used
+   for attributes of ``<link>`` tag.  It defaults to an empty list.
+
+   Example::
+
+       html_css_files = ['custom.css'
+                         'https://example.com/css/custom.css',
+                         ('print.css', {'media': 'print'})]
+
+   .. versionadded:: 1.8
+
 .. confval:: html_static_path
 
    A list of paths that contain custom static files (such as style

sphinx/builders/html.py

@@ -154,6 +154,7 @@ class Stylesheet(text_type):
         self.filename = filename
         self.attributes = attributes
         self.attributes.setdefault('rel', 'stylesheet')
+        self.attributes.setdefault('type', 'text/css')
         if args:  # old style arguments (rel, title)
             self.attributes['rel'] = args[0]
             self.attributes['title'] = args[1]
@@ -342,6 +343,22 @@ class StandaloneHTMLBuilder(Builder):
         for filename, attrs in self.app.registry.css_files:
             self.css_files.append(Stylesheet(filename, **attrs))  # type: ignore
 
+        for entry in self.get_builder_config('css_files', 'html'):
+            if isinstance(entry, string_types):
+                filename = entry
+                attrs = {}
+            else:
+                try:
+                    filename, attrs = entry
+                except (TypeError, ValueError):
+                    logger.warning('invalid css_file: %r', entry)
+                    continue
+
+            if '://' not in filename:
+                filename = path.join('_static', filename)
+
+            self.css_files.append(Stylesheet(filename, **attrs))  # type: ignore
+
     @property
     def default_translator_class(self):
         # type: () -> nodes.NodeVisitor
@@ -1008,9 +1025,11 @@ class StandaloneHTMLBuilder(Builder):
 
         def css_tag(css):
             # type: (Stylesheet) -> unicode
-            attrs = ['%s="%s"' % (key, htmlescape(value, True))
-                     for key, value in css.attributes.items()
-                     if value is not None]
+            attrs = []
+            for key in sorted(css.attributes):
+                value = css.attributes[key]
+                if value is not None:
+                    attrs.append('%s="%s"' % (key, htmlescape(value, True)))
             attrs.append('href="%s"' % pathto(css.filename, resource=True))
             return '<link %s />' % ' '.join(attrs)
         ctx['css_tag'] = css_tag
@@ -1468,6 +1487,7 @@ def setup(app):
     app.add_config_value('html_style', None, 'html', string_classes)
     app.add_config_value('html_logo', None, 'html', string_classes)
     app.add_config_value('html_favicon', None, 'html', string_classes)
+    app.add_config_value('html_css_files', [], 'html')
     app.add_config_value('html_static_path', [], 'html')
     app.add_config_value('html_extra_path', [], 'html')
     app.add_config_value('html_last_updated_fmt', None, 'html', string_classes)

tests/roots/test-html_assets/conf.py

@@ -6,4 +6,6 @@ version = '1.4.4'
 
 html_static_path = ['static', 'subdir']
 html_extra_path = ['extra', 'subdir']
+html_css_files = ['css/style.css',
+                  ('https://example.com/custom.css', {'title': 'title', 'media': 'print'})]
 exclude_patterns = ['**/_build', '**/.htpasswd']

tests/test_build_html.py

@@ -1094,9 +1094,10 @@ def test_html_assets(app):
     assert not (app.outdir / '_static' / '.htpasswd').exists()
     assert (app.outdir / '_static' / 'API.html').exists()
     assert (app.outdir / '_static' / 'API.html').text() == 'Sphinx-1.4.4'
-    assert (app.outdir / '_static' / 'css/style.css').exists()
+    assert (app.outdir / '_static' / 'css' / 'style.css').exists()
+    assert (app.outdir / '_static' / 'js' / 'custom.js').exists()
     assert (app.outdir / '_static' / 'rimg.png').exists()
-    assert not (app.outdir / '_static' / '_build/index.html').exists()
+    assert not (app.outdir / '_static' / '_build' / 'index.html').exists()
     assert (app.outdir / '_static' / 'background.png').exists()
     assert not (app.outdir / '_static' / 'subdir' / '.htaccess').exists()
     assert not (app.outdir / '_static' / 'subdir' / '.htpasswd').exists()
@@ -1107,11 +1108,17 @@ def test_html_assets(app):
     assert (app.outdir / 'API.html_t').exists()
     assert (app.outdir / 'css/style.css').exists()
     assert (app.outdir / 'rimg.png').exists()
-    assert not (app.outdir / '_build/index.html').exists()
+    assert not (app.outdir / '_build' / 'index.html').exists()
     assert (app.outdir / 'background.png').exists()
     assert (app.outdir / 'subdir' / '.htaccess').exists()
     assert not (app.outdir / 'subdir' / '.htpasswd').exists()
 
+    # html_css_files
+    content = (app.outdir / 'index.html').text()
+    assert '<link rel="stylesheet" type="text/css" href="_static/css/style.css" />' in content
+    assert ('<link media="print" rel="stylesheet" title="title" type="text/css" '
+            'href="https://example.com/custom.css" />' in content)
+
 
 @pytest.mark.sphinx('html', testroot='basic', confoverrides={'html_copy_source': False})
 def test_html_copy_source(app):