Add frozendict support to _safe_repr()

Author: vstinner

Lib/pprint.py

@@ -637,12 +637,21 @@ def _safe_repr(self, object, context, maxlevels, level):
             else:
                 return repr(object), True, False
 
-        if issubclass(typ, dict) and r is dict.__repr__:
+        if ((issubclass(typ, dict) and r is dict.__repr__)
+            or (issubclass(typ, frozendict) and r is frozendict.__repr__)):
+            is_frozendict = issubclass(typ, frozendict)
             if not object:
-                return "{}", True, False
+                if is_frozendict:
+                    rep = f"{object.__class__.__name__}()"
+                else:
+                    rep = "{}"
+                return rep, True, False
             objid = id(object)
             if maxlevels and level >= maxlevels:
-                return "{...}", False, objid in context
+                rep = "{...}"
+                if is_frozendict:
+                    rep = f"{object.__class__.__name__}({rep})"
+                return rep, False, objid in context
             if objid in context:
                 return _recursion(object), False, True
             context[objid] = 1
@@ -665,7 +674,10 @@ def _safe_repr(self, object, context, maxlevels, level):
                 if krecur or vrecur:
                     recursive = True
             del context[objid]
-            return "{%s}" % ", ".join(components), readable, recursive
+            rep = "{%s}" % ", ".join(components)
+            if is_frozendict:
+                rep = f"{object.__class__.__name__}({rep})"
+            return rep, readable, recursive
 
         if (issubclass(typ, list) and r is list.__repr__) or \
            (issubclass(typ, tuple) and r is tuple.__repr__):