Fix property getter annotations

- Sphinx doesn't parse pybind11's property annotations

robotpy_sphinx/pybind11_fixer.py

@@ -1,3 +1,4 @@
+import inspect
 from typing import Optional, Tuple
 
 
@@ -10,6 +11,21 @@ def process_signature(
     signature: Optional[str],
     return_annotation: Optional[str],
 ) -> Optional[Tuple[str, Optional[str]]]:
+    # sphinx completely ignores pybind11 property annotations, so fix them
+    if what == "property":
+        # If sphinx figured it out, no need to override it
+        if signature:
+            return signature, return_annotation
+
+        if hasattr(obj, "fget"):
+            fdoc = inspect.getdoc(obj.fget)
+            if fdoc and fdoc.startswith("(self:"):
+                s = fdoc.split("->")
+                if len(s) == 2:
+                    return "(self)", s[1]
+
+        return
+
     if what not in ("class", "method") or signature is None:
         return