Fix printing for CircuitSpecs

Author: jzaia18

pennylane/resource/resource.py

@@ -481,6 +481,22 @@ def __getitem__(self, key):
             f"key '{key}' not available. Options are {[field.name for field in fields(self)]}"
         )
 
+    def _print_resources(self, res) -> str:
+        """Helper for printing resources, prints list or single SpecsResources."""
+        lines = []
+        if isinstance(res, SpecsResources):
+            lines.append(res.to_pretty_str(preindent=2))
+        elif isinstance(res, list):
+            for i, res in enumerate(res):
+                lines.append(f"  Batched tape {i}:")
+                lines.append(res.to_pretty_str(preindent=4))
+        else:
+            raise ValueError(
+                "Resources must be either a SpecsResources object or a list of SpecsResources objects."
+            )
+
+        return "\n".join(lines)
+
     # Separate str and repr methods for simple and pretty printing
     def __str__(self):
         lines = []
@@ -493,14 +509,13 @@ def __str__(self):
         lines.append("")  # Blank line
 
         lines.append("Resource specifications:")
-        if isinstance(self.resources, SpecsResources):
-            lines.append(self.resources.to_pretty_str(preindent=2))
-        else:
+        if isinstance(self.resources, dict):
             for level, res in self.resources.items():
                 lines.append(f"Level = {level}:")
-                lines.append(res.to_pretty_str(preindent=2))
-
+                self._print_resources(res)
                 lines.append("\n" + "-" * 60 + "\n")  # Separator between levels
+        else:
+            lines.append(self._print_resources(self.resources))
 
         return "\n".join(lines).rstrip("\n-")
 

tests/resource/test_specs.py

@@ -328,6 +328,55 @@ def circuit(x):
         assert specs_output.num_device_wires is None
         assert specs_output.shots == Shots(None)
 
+        assert (
+            str(specs_output)
+            == """Device: default.qubit
+Device wires: None
+Shots: Shots(total=None)
+Level: 2
+
+Resource specifications:
+  Batched tape 0:
+    Total qubit allocations: 2
+    Total gates: 5
+    Circuit depth: 5
+
+    Gate types:
+      RandomLayers: 1
+      RX: 1
+      SWAP: 1
+      PauliX: 2
+
+    Measurements:
+      expval(PauliX @ PauliZ): 1
+  Batched tape 1:
+    Total qubit allocations: 3
+    Total gates: 5
+    Circuit depth: 5
+
+    Gate types:
+      RandomLayers: 1
+      RX: 1
+      SWAP: 1
+      PauliX: 2
+
+    Measurements:
+      expval(PauliZ @ PauliY): 1
+  Batched tape 2:
+    Total qubit allocations: 3
+    Total gates: 5
+    Circuit depth: 5
+
+    Gate types:
+      RandomLayers: 1
+      RX: 1
+      SWAP: 1
+      PauliX: 2
+
+    Measurements:
+      expval(PauliY @ PauliX): 1"""
+        )
+
     @pytest.mark.parametrize(
         "device,num_wires",
         devices_list,