Fix Subscript rendering in both printing paths

graphtage/ast.py

@@ -87,7 +87,7 @@ def print(self, printer: Printer):
         self.value.print(printer)
         with printer.color(Fore.LIGHTBLUE_EX):
             printer.write("[")
-        self.slice.write(printer)
+        self.slice.print(printer)
         with printer.color(Fore.LIGHTBLUE_EX):
             printer.write("]")
 

graphtage/pydiff.py

@@ -433,7 +433,7 @@ def print_Subscript(self, printer: Printer, node: Subscript):
             printer.write("[")
         self.print(printer, node.slice)
         with printer.color(Fore.BLUE):
-            printer.write("[")
+            printer.write("]")
 
 
 def diff(from_py_obj, to_py_obj, options: BuildOptions | None = None):

test/test_pydiff.py

@@ -4,6 +4,7 @@
 from unittest import TestCase
 
 import graphtage
+from graphtage.ast import Subscript
 from graphtage.printer import Printer
 from graphtage.pydiff import PyDiffFormatter, PyObjAttribute, ast_to_tree, build_tree, print_diff
 
@@ -71,6 +72,28 @@ def test_nested_tuple_diff(self):
         self.assertIsInstance(kvp.key, graphtage.StringNode)
         self.assertIsInstance(kvp.value, graphtage.ListNode)
 
+    def _only_subscript(self, source: str) -> Subscript:
+        subscripts = [node for node in ast_to_tree(ast.parse(source)).dfs() if isinstance(node, Subscript)]
+        self.assertEqual(1, len(subscripts))
+        return subscripts[0]
+
+    def test_subscript_node_print(self):
+        """Reproduces the ``TreeNode.write`` half of https://github.com/trailofbits/graphtage/issues/154
+
+        ``Subscript.print`` is the fallback that :meth:`graphtage.tree.GraphtageFormatter.print` uses when no
+        formatter resolves the node type, so this calls it directly rather than through a formatter.
+
+        """
+        stream = StringIO()
+        self._only_subscript("a[1]").print(Printer(out_stream=stream, ansi_color=False))
+        self.assertEqual("a[1]", stream.getvalue())
+
+    def test_subscript_formatter_print(self):
+        """Reproduces the unbalanced bracket half of https://github.com/trailofbits/graphtage/issues/154"""
+        stream = StringIO()
+        node = self._only_subscript("a[1]")
+        PyDiffFormatter.DEFAULT_INSTANCE.print(Printer(out_stream=stream, ansi_color=False), node)
+        self.assertEqual("a[1]", stream.getvalue())
     def test_dataclass_edit_preserves_syntax(self):
         """Reproduces https://github.com/trailofbits/graphtage/issues/150