Fix Node.find_by_path() to allow empty array suffixes

Author: amykyta3

src/systemrdl/node.py

@@ -360,11 +360,15 @@ def find_by_path(self, path: str) -> Optional['Node']:
                 continue
 
             # .. otherwise continue parsing the path
-            m = re.fullmatch(r'^(\w+)((?:\[(?:\d+|0[xX][\da-fA-F]+)\])*)$', pathpart)
+            m = re.fullmatch(r'(\w+)(.*)', pathpart)
             if not m:
                 raise ValueError("Invalid path")
             inst_name, array_suffix = m.group(1, 2)
-            idx_list = [int(s, 0) for s in re.findall(r'\[(\d+|0[xX][\da-fA-F]+)\]', array_suffix)]
+            if array_suffix == "" or re.fullmatch(r"(\[\])+", array_suffix):
+                # No indexes specified
+                idx_list = []
+            else:
+                idx_list = [int(s, 0) for s in re.findall(r'\[(\d+|0[xX][\da-fA-F]+)\]', array_suffix)]
 
             current_node = current_node.get_child_by_name(inst_name)
             if current_node is None:

test/test_node_utils.py

@@ -1,9 +1,25 @@
 from unittest_utils import RDLSourceTestCase
 from systemrdl.rdltypes import PrecedenceType
-from systemrdl.node import RegNode, FieldNode, RegfileNode, AddrmapNode, SignalNode, MemNode
+from systemrdl.node import RegNode, FieldNode, RegfileNode, AddrmapNode
 
 class TestNodeUtils(RDLSourceTestCase):
 
+    def test_find_by_path(self):
+        top = self.compile(
+            ["rdl_src/address_packing.rdl"],
+            "hier"
+        )
+
+
+        node = top.find_by_path("hier.y[2].a[0][1]")
+        self.assertEqual(node.get_path(), "hier.y[2].a[0][1]")
+
+        node = top.find_by_path("hier.y.a")
+        self.assertEqual(node.get_path(), "hier.y[].a[][]")
+
+        node = top.find_by_path("hier.y[].a[][]")
+        self.assertEqual(node.get_path(), "hier.y[].a[][]")
+
     def test_index_tools(self):
         top = self.compile(
             ["rdl_src/address_packing.rdl"],