[core] Correctly match descriptions for connected attributes within groups

Author: cbentejac

meshroom/core/attribute.py

@@ -340,7 +340,7 @@ def _applyExpr(self):
         elif self.isInput and Attribute.isLinkExpression(v):
             # value is a link to another attribute
             link = v[1:-1]
-            linkNode, linkAttr = link.split('.')
+            linkNode, linkAttr = link.split('.', 1)
             try:
                 g.addEdge(g.node(linkNode).attribute(linkAttr), self)
             except KeyError as err:

meshroom/core/node.py

@@ -1711,9 +1711,18 @@ def attributeDescFromName(refAttributes, name, value, strict=True):
         attrDesc = next((d for d in refAttributes if d.name == name), None)
         if attrDesc is None:
             return None
+
         # We have found a description, and we still need to
         # check if the value matches the attribute description.
-        #
+
+        # If it is a GroupAttribute, all attributes within the group should be matched individually
+        # so that links that can be correctly evaluated
+        if isinstance(attrDesc, desc.GroupAttribute):
+            for k, v in value.items():
+                if CompatibilityNode.attributeDescFromName(attrDesc.groupDesc, k, v, strict=True) is None:
+                    return None
+            return attrDesc
+
         # If it is a serialized link expression (no proper value to set/evaluate)
         if Attribute.isLinkExpression(value):
             return attrDesc