Updated stub file

---

+ Removed field related tests

src/ccaterpillar/atomimpl/builtins/atoffset.c

@@ -166,6 +166,7 @@ CpOffsetAtom_Unpack(CpOffsetAtomObject* self, CpLayerObject* layer)
 static PyMemberDef CpOffsetAtom_Members[] = {
   { "offset", T_OBJECT_EX, offsetof(CpOffsetAtomObject, m_offset), READONLY },
   { "whence", T_OBJECT_EX, offsetof(CpOffsetAtomObject, m_whence), READONLY },
+  { "atom", T_OBJECT_EX, offsetof(CpOffsetAtomObject, m_atom), READONLY },
   { NULL } /* Sentinel */
 };
 

src/ccaterpillar/atomimpl/builtins/switch.c

@@ -136,7 +136,7 @@ _CpEndian_ImplSetByteorder(CpSwitchAtomObject, switchatom, self->m_atom);
 static PyObject*
 cp_switchatom_get_next(CpSwitchAtomObject* self, PyObject* args, PyObject* kw)
 {
-  static char* kwlist[] = { "atom", "context", NULL };
+  static char* kwlist[] = { "obj", "context", NULL };
   PyObject* op = NULL;
   PyObject* context = NULL;
   if (!PyArg_ParseTupleAndKeywords(args, kw, "OO", kwlist, &op, &context)) {

src/ccaterpillar/atomimpl/cstring.c

@@ -295,6 +295,11 @@ static PyMemberDef CpCStringAtom_Members[] = {
     offsetof(CpCStringAtomObject, s_keep_terminator),
     0,
     "whether to keep the terminator" },
+  { "length",
+    T_OBJECT_EX,
+    offsetof(CpCStringAtomObject, m_length),
+    0,
+    "the length of the string" },
   { NULL }
 };
 
@@ -304,7 +309,7 @@ PyTypeObject CpCStringAtom_Type = {
   .tp_itemsize = 0,
   .tp_dealloc = (destructor)cp_cstringatom_dealloc,
   .tp_repr = (reprfunc)cp_cstringatom_repr,
-  .tp_flags = Py_TPFLAGS_DEFAULT,
+  .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
   .tp_new = (newfunc)cp_cstringatom_new,
   .tp_members = CpCStringAtom_Members,
   .tp_init = (initproc)cp_cstringatom_init,

src/ccaterpillar/atomimpl/pstring.c

@@ -158,7 +158,7 @@ PyTypeObject CpPStringAtom_Type = {
   PyVarObject_HEAD_INIT(NULL, 0) _Cp_NameStr(CpPStringAtom_NAME),
   .tp_basicsize = sizeof(CpPStringAtomObject),
   .tp_dealloc = (destructor)cp_pstringatom_dealloc,
-  .tp_flags = Py_TPFLAGS_DEFAULT,
+  .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
   .tp_doc = NULL,
   .tp_members = CpPStringAtom_Members,
   .tp_init = (initproc)cp_pstringatom_init,

test/_C/test_atom.py

@@ -4,7 +4,7 @@
 
 if caterpillar.native_support():
 
-    from caterpillar._C import atom, catom, fieldatom, fieldcatom
+    from caterpillar._C import atom, catom
 
 
     def test_atom_init():
@@ -26,8 +26,6 @@ class Foo(atom):
 
         assert issubclass(Foo, atom)
         assert issubclass(catom, atom)
-        assert issubclass(fieldatom, atom)
-        assert issubclass(fieldcatom, catom)
 
 
     def test_atom_methods():

test/_C/test_parsing.py

@@ -5,7 +5,8 @@
 
 if caterpillar.native_support():
 
-    from caterpillar._C import atom, typeof, Field, sizeof, patom
+    from caterpillar._C import atom, typeof, sizeof, patom, repeated
+    from caterpillar._C import switch
     from caterpillar._C import unpack, layer, Struct, pack, ContextPath
 
 
@@ -42,16 +43,16 @@ def test_typeof():
 
         # That will change if we have a field with a length or a
         # switch statement.
-        field = Field(f, length=2)
+        field = repeated(f, 2)
         assert typeof(field) == typing.List[str]
 
-        field2 = Field(f, switch={1: atom()})
+        field2 = switch(f, {1: atom()})[2]
         # We can't know the type of a switch atom which does
         # not implement the __type__ method
-        assert typeof(Field(atom())) == typing.Any
-        assert typeof(field2) == typing.Union[typing.Any, str]
+        assert typeof(atom()) == typing.Any
+        assert typeof(field2) == typing.List[typing.Any]
         # switch and length can be combined as well
-        assert typeof(field2[2]) == typing.List[typing.Union[typing.Any, str]]
+        assert typeof(field2[2]) == typing.List[typing.List[typing.Any]]
 
 
     def test_sizeof():
@@ -73,8 +74,10 @@ def test_sizeof():
         # Calculation is done by first evaluating the length of
         # the field's atom and then multiply the length of the evalutated
         # switch atom by the field's length.
-        field = Field(b, length=2, switch=(lambda ctx: Bar()))
-        assert sizeof(field) == 2 + (2 * 2)
+        # REVISIT: switch atoms does not have a static size
+        with pytest.raises(TypeError):
+            field = switch(b, (lambda ctx: Bar()))[2]
+            assert sizeof(field) == 2 + (2 * 2)
 
 
     def test_unpack_basic():