Do not remove reftitle because it breaks other extensions

#86 (comment)

There are other extensions that expect `reftitle` to be an attribute in the
node. They are doing `node['reftitle']` without checking if it exists first.

This happens in `sphinx.ext.inheritance_diagram` which is a built-in extension.
So it's preferrable to not modify the node and find another way to remove the
browser's tooltip later.

See https://github.com/sphinx-doc/sphinx/blob/4.x/sphinx/ext/inheritance_diagram.py#L413

Author: humitos

hoverxref/extension.py

@@ -241,11 +241,6 @@ def missing_reference(app, env, node, contnode):
             'data-url': newnode.get('refuri'),
         }
 
-        # Remove ``title=`` from HTML tag to avoid showing the title of the
-        # reference when hovering, which is a little confusing
-        if 'reftitle' in  newnode:
-            del newnode['reftitle']
-
     return newnode
 
 

tests/test_htmltag.py

@@ -252,9 +252,9 @@ def test_intersphinx_python_mapping(app, status, warning):
 
     chunks = [
         # Python's links do have hoverxref enabled
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/tutorial/index.html#tutorial-index" href="https://docs.python.org/3/tutorial/index.html#tutorial-index"><span class="xref std std-ref">This a :ref: to The Python Tutorial using intersphinx</span></a>',
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/datetime.html#datetime-datetime" href="https://docs.python.org/3/library/datetime.html#datetime-datetime"><span class="xref std std-ref">This a :ref: to datetime.datetime Python’s function using intersphinx</span></a>',
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/functions.html#float" href="https://docs.python.org/3/library/functions.html#float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/tutorial/index.html#tutorial-index" href="https://docs.python.org/3/tutorial/index.html#tutorial-index" title="(in Python v3.9)"><span class="xref std std-ref">This a :ref: to The Python Tutorial using intersphinx</span></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/datetime.html#datetime-datetime" href="https://docs.python.org/3/library/datetime.html#datetime-datetime" title="(in Python v3.9)"><span class="xref std std-ref">This a :ref: to datetime.datetime Python’s function using intersphinx</span></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/functions.html#float" href="https://docs.python.org/3/library/functions.html#float" title="(in Python v3.9)"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a>',
 
         # Read the Docs' link does not have hoverxref enabled
         '<a class="reference external" href="https://docs.readthedocs.io/en/stable/config-file/v2.html#python" title="(in Read the Docs v5.17.0)"><span class="xref std std-ref">This a :ref: to Config File v2 Read the Docs’ page using intersphinx</span></a>',
@@ -288,12 +288,12 @@ def test_intersphinx_all_mappings(app, status, warning):
 
     chunks = [
         # Python's links do have hoverxref enabled
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/tutorial/index.html#tutorial-index" href="https://docs.python.org/3/tutorial/index.html#tutorial-index"><span class="xref std std-ref">This a :ref: to The Python Tutorial using intersphinx</span></a>',
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/datetime.html#datetime-datetime" href="https://docs.python.org/3/library/datetime.html#datetime-datetime"><span class="xref std std-ref">This a :ref: to datetime.datetime Python’s function using intersphinx</span></a>',
-        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/functions.html#float" href="https://docs.python.org/3/library/functions.html#float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/tutorial/index.html#tutorial-index" href="https://docs.python.org/3/tutorial/index.html#tutorial-index" title="(in Python v3.9)"><span class="xref std std-ref">This a :ref: to The Python Tutorial using intersphinx</span></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/datetime.html#datetime-datetime" href="https://docs.python.org/3/library/datetime.html#datetime-datetime" title="(in Python v3.9)"><span class="xref std std-ref">This a :ref: to datetime.datetime Python’s function using intersphinx</span></a>',
+        '<a class="hoverxref tooltip reference external" data-url="https://docs.python.org/3/library/functions.html#float" href="https://docs.python.org/3/library/functions.html#float" title="(in Python v3.9)"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a>',
 
         # Read the Docs' link does have hoverxref enabled
-        '<a class="hoverxref modal reference external" data-url="https://docs.readthedocs.io/en/stable/config-file/v2.html#python" href="https://docs.readthedocs.io/en/stable/config-file/v2.html#python"><span class="xref std std-ref">This a :ref: to Config File v2 Read the Docs’ page using intersphinx</span></a>',
+        '<a class="hoverxref modal reference external" data-url="https://docs.readthedocs.io/en/stable/config-file/v2.html#python" href="https://docs.readthedocs.io/en/stable/config-file/v2.html#python" title="(in Read the Docs v5.17.0)"><span class="xref std std-ref">This a :ref: to Config File v2 Read the Docs’ page using intersphinx</span></a>',
 
         # Python domain's link does have hoverxref enabled
         '<a class="hoverxref tooltip reference internal" data-doc="index" data-docpath="/index.html" data-project="myproject" data-section="hoverxref.extension.setup" data-version="myversion" href="#hoverxref.extension.setup" title="hoverxref.extension.setup"><code class="xref py py-func docutils literal notranslate"><span class="pre">hoverxref.extension.setup()</span></code></a>',