Close #6241: html: Allow to add JS/CSS files to the specific page

Allow to add JS/CSS files to the specific page when an extension calls
`app.add_js_file()` or `app.add_css_file()` on `html-page-context`
event.

1 files changed, 13 insertions, 0 deletions

diff --git a/tests/test_ext_math.py b/tests/test_ext_math.py
index 28c2c35a5..10c8c4866 100644
--- a/tests/test_ext_math.py
+++ b/tests/test_ext_math.py
@@ -15,6 +15,7 @@ import warnings
 import pytest
 from docutils import nodes
 
+from sphinx.ext.mathjax import MATHJAX_URL
 from sphinx.testing.util import assert_node
 
 
@@ -224,6 +225,18 @@ def test_mathjax_config(app, status, warning):
             '</script>' in content)
 
 
+@pytest.mark.sphinx('html', testroot='ext-math',
+                    confoverrides={'extensions': ['sphinx.ext.mathjax']})
+def test_mathjax_is_installed_only_if_document_having_math(app, status, warning):
+    app.builder.build_all()
+
+    content = (app.outdir / 'index.html').read_text()
+    assert MATHJAX_URL in content
+
+    content = (app.outdir / 'nomath.html').read_text()
+    assert MATHJAX_URL not in content
+
+
 @pytest.mark.sphinx('html', testroot='basic',
                     confoverrides={'extensions': ['sphinx.ext.mathjax']})
 def test_mathjax_is_not_installed_if_no_equations(app, status, warning):