Fix dumpstruct for anonymous structures

dissect/cstruct/utils.py

@@ -135,7 +135,10 @@ def _dumpstruct(
     ci = 0
     out = [f"struct {structure.name}:"]
     foreground, background = None, None
-    for field in instance._type.fields:
+    for field in instance._type.lookup.values():
+        if getattr(field.type, "anonymous", False):
+            continue
+
         if color:
             foreground, background = colors[ci % len(colors)]
             palette.append((instance._size(field.name), background))

tests/test_util.py

@@ -28,6 +28,42 @@ def test_dumpstruct(capsys, compiled):
         uint32 testval;
     };
     """
+
+    cs = cstruct.cstruct()
+    cs.load(cdef, compiled=compiled)
+
+    assert verify_compiled(cs.test, compiled)
+
+    buf = b"\x39\x05\x00\x00"
+    obj = cs.test(buf)
+
+    dumpstruct(cs.test, buf)
+    captured_1 = capsys.readouterr()
+
+    dumpstruct(obj)
+    captured_2 = capsys.readouterr()
+
+    assert captured_1.out == captured_2.out
+
+    out_1 = dumpstruct(cs.test, buf, output="string")
+    out_2 = dumpstruct(obj, output="string")
+
+    assert out_1 == out_2
+
+    with pytest.raises(ValueError) as excinfo:
+        dumpstruct(obj, output="generator")
+    assert str(excinfo.value) == "Invalid output argument: 'generator' (should be 'print' or 'string')."
+
+
+def test_dumpstruct_anonymous(capsys, compiled):
+    cdef = """
+    struct test {
+        struct {
+            uint32 testval;
+        };
+    };
+    """
+
     cs = cstruct.cstruct()
     cs.load(cdef, compiled=compiled)