From 36c6eafdf17edeaec3c902d15cc757edb3937d5d Mon Sep 17 00:00:00 2001
From: Jakob Lykke Andersen <Jakob@caput.dk>
Date: Tue, 13 Jul 2021 13:41:41 +0200
Subject: [PATCH] intersphinx: explicitly parse out inventory specification

---
 sphinx/ext/intersphinx.py                       | 13 +++++++++++++
 tests/roots/test-ext-intersphinx-role/index.rst |  1 +
 tests/test_ext_intersphinx.py                   |  2 ++
 3 files changed, 16 insertions(+)

diff --git a/sphinx/ext/intersphinx.py b/sphinx/ext/intersphinx.py
index 3cfbdf1dd..d004f867f 100644
--- a/sphinx/ext/intersphinx.py
+++ b/sphinx/ext/intersphinx.py
@@ -495,10 +495,20 @@ class IntersphinxRole(SphinxRole):
                            location=(self.env.docname, self.lineno))
             return [], []
 
+        # extract inventory specification
+        inventory = None
+        if self.text.startswith('\\:'):
+            # escaped :, so not a real inventory specification
+            self.text = self.text[1:]
+        elif self.text[0] == ':':  # format: :inv:normalRoleArg
+            inventory = self.text.split(':')[1]
+            self.text = self.text[(len(inventory) + 2):]
+
         result, messages = self.invoke_role(role_name)
         for node in result:
             if isinstance(node, pending_xref):
                 node['intersphinx'] = True
+                node['inventory'] = inventory
 
         return result, messages
 
@@ -555,6 +565,9 @@ class IntersphinxRoleResolver(ReferencesResolver):
         for node in self.document.traverse(pending_xref):
             if 'intersphinx' in node:
                 contnode = cast(nodes.TextElement, node[0].deepcopy())
+                # temporary hax to glue on inventory info again
+                if node['inventory'] is not None:
+                    node['reftarget'] = node['inventory'] + ":" + node['reftarget']
                 newnode = missing_reference(self.app, self.env, node, contnode)
                 if newnode is None:
                     # no warning, the normal missing_reference handler will do that
diff --git a/tests/roots/test-ext-intersphinx-role/index.rst b/tests/roots/test-ext-intersphinx-role/index.rst
index 4eeaf807a..164f2cfd4 100644
--- a/tests/roots/test-ext-intersphinx-role/index.rst
+++ b/tests/roots/test-ext-intersphinx-role/index.rst
@@ -20,6 +20,7 @@
 
 :external:cpp:type:`std::uint8_t`
 :external:cpp:class:`inv:foo::Bar`
+:external:cpp:func:`:inv2:foo::Bar::baz`
 
 :external:cpp:type:`FoonsTitle <foons>`
 :external:cpp:type:`inv:BarType <foons::bartype>`
\ No newline at end of file
diff --git a/tests/test_ext_intersphinx.py b/tests/test_ext_intersphinx.py
index a2ff8d7ac..a1118e48d 100644
--- a/tests/test_ext_intersphinx.py
+++ b/tests/test_ext_intersphinx.py
@@ -558,3 +558,5 @@ def test_intersphinx_role(app):
     html = '<a class="reference external" href="http://example.org/{}" title="(in foo v2.0)">'
     for t in targets:
         assert html.format(t) in content
+
+    assert html.format('index.html#cpp_foo_bar_baz') not in content