add nested dict support

lupa/_lupa.pyx

@@ -48,10 +48,11 @@ cdef object exc_info
 from sys import exc_info
 
 cdef object Mapping
+cdef object Sequence
 try:
-    from collections.abc import Mapping
+    from collections.abc import Mapping, Sequence
 except ImportError:
-    from collections import Mapping  # Py2
+    from collections import Mapping, Sequence  # Py2
 
 cdef object wraps
 from functools import wraps
@@ -156,6 +157,10 @@ def lua_type(obj):
         lua.lua_settop(L, old_top)
         unlock_runtime(lua_object._runtime)
 
+cdef inline int _len_as_int(Py_ssize_t obj) except -1:
+    if obj > <Py_ssize_t>INT_MAX:
+        raise OverflowError
+    return <int>obj
 
 @cython.no_gc_clear
 cdef class LuaRuntime:
@@ -408,15 +413,15 @@ cdef class LuaRuntime:
         """
         return self.table_from(items, kwargs)
 
-    def table_from(self, *args):
+    def table_from(self, *args, bint recursive=False):
         """Create a new table from Python mapping or iterable.
 
         table_from() accepts either a dict/mapping or an iterable with items.
         Items from dicts are set as key-value pairs; items from iterables
         are placed in the table in order.
 
         Nested mappings / iterables are passed to Lua as userdata
-        (wrapped Python objects); they are not converted to Lua tables.
+        (wrapped Python objects) if recursive is False; they are not converted to Lua tables.
         """
         assert self._state is not NULL
         cdef lua_State *L = self._state
@@ -426,12 +431,12 @@ cdef class LuaRuntime:
         try:
             check_lua_stack(L, 5)
             lua.lua_newtable(L)
-            # FIXME: how to check for failure?
+            # FIXME: how to check for failure? and nested dict
             for obj in args:
                 if isinstance(obj, dict):
                     for key, value in obj.iteritems():
-                        py_to_lua(self, L, key)
-                        py_to_lua(self, L, value)
+                        py_to_lua(self, L, key, wrap_none=False, recursive=recursive)
+                        py_to_lua(self, L, value, wrap_none=False, recursive=recursive)
                         lua.lua_rawset(L, -3)
 
                 elif isinstance(obj, _LuaTable):
@@ -447,12 +452,12 @@ cdef class LuaRuntime:
                 elif isinstance(obj, Mapping):
                     for key in obj:
                         value = obj[key]
-                        py_to_lua(self, L, key)
-                        py_to_lua(self, L, value)
+                        py_to_lua(self, L, key, wrap_none=False, recursive=recursive)
+                        py_to_lua(self, L, value, wrap_none=False, recursive=recursive)
                         lua.lua_rawset(L, -3)
                 else:
                     for arg in obj:
-                        py_to_lua(self, L, arg)
+                        py_to_lua(self, L, arg, wrap_none=False, recursive=recursive)
                         lua.lua_rawseti(L, -2, i)
                         i += 1
             return py_from_lua(self, L, -1)
@@ -1135,7 +1140,7 @@ cdef object resume_lua_thread(_LuaThread thread, tuple args):
             # already terminated
             raise StopIteration
         if args:
-            nargs = len(args)
+            nargs = _len_as_int(len(args))
             push_lua_arguments(thread._runtime, co, args)
         with nogil:
             status = lua.lua_resume(co, L, nargs, &nres)
@@ -1381,7 +1386,7 @@ cdef py_object* unpack_userdata(lua_State *L, int n) nogil:
 cdef int py_function_result_to_lua(LuaRuntime runtime, lua_State *L, object o) except -1:
      if runtime._unpack_returned_tuples and isinstance(o, tuple):
          push_lua_arguments(runtime, L, <tuple>o)
-         return len(<tuple>o)
+         return _len_as_int(len(<tuple>o))
      check_lua_stack(L, 1)
      return py_to_lua(runtime, L, o)
 
@@ -1410,7 +1415,7 @@ cdef int py_to_lua_handle_overflow(LuaRuntime runtime, lua_State *L, object o) e
         lua.lua_settop(L, old_top)
         raise
 
-cdef int py_to_lua(LuaRuntime runtime, lua_State *L, object o, bint wrap_none=False) except -1:
+cdef int py_to_lua(LuaRuntime runtime, lua_State *L, object o, bint wrap_none=False, bint recursive=False) except -1:
     """Converts Python object to Lua
     Preconditions:
         1 extra slot in the Lua stack
@@ -1462,13 +1467,26 @@ cdef int py_to_lua(LuaRuntime runtime, lua_State *L, object o, bint wrap_none=Fa
     elif isinstance(o, float):
         lua.lua_pushnumber(L, <lua.lua_Number><double>o)
         pushed_values_count = 1
+    elif isinstance(o, _PyProtocolWrapper):
+        type_flags = (<_PyProtocolWrapper> o)._type_flags
+        o = (<_PyProtocolWrapper> o)._obj
+        pushed_values_count = py_to_lua_custom(runtime, L, o, type_flags)
+    elif recursive and isinstance(o, (list, Sequence)):
+        lua.lua_createtable(L, _len_as_int(len(o)), 0)   # create a table at the top of stack, with narr already known
+        for i, v in enumerate(o, 1):
+            py_to_lua(runtime, L, v, wrap_none, recursive)
+            lua.lua_rawseti(L, -2, i)
+        pushed_values_count = 1
+    elif recursive and isinstance(o, (dict, Mapping)):
+        lua.lua_createtable(L, 0, _len_as_int(len(o)))  # create a table at the top of stack, with nrec already known
+        for key, value in o.items():
+            py_to_lua(runtime, L, key, wrap_none, recursive)
+            py_to_lua(runtime, L, value, wrap_none, recursive)
+            lua.lua_rawset(L, -3)
+        pushed_values_count = 1
     else:
-        if isinstance(o, _PyProtocolWrapper):
-            type_flags = (<_PyProtocolWrapper>o)._type_flags
-            o = (<_PyProtocolWrapper>o)._obj
-        else:
-            # prefer __getitem__ over __getattr__ by default
-            type_flags = OBJ_AS_INDEX if hasattr(o, '__getitem__') else 0
+        # prefer __getitem__ over __getattr__ by default
+        type_flags = OBJ_AS_INDEX if hasattr(o, '__getitem__') else 0
         pushed_values_count = py_to_lua_custom(runtime, L, o, type_flags)
     return pushed_values_count
 
@@ -1776,7 +1794,7 @@ cdef int py_object_gc_with_gil(py_object *py_obj, lua_State* L) with gil:
         return 0
     finally:
         py_obj.obj = NULL
-    
+
 cdef int py_object_gc(lua_State* L) nogil:
     if not lua.lua_isuserdata(L, 1):
         return 0
@@ -1802,7 +1820,7 @@ cdef bint call_python(LuaRuntime runtime, lua_State *L, py_object* py_obj) excep
     else:
         args = ()
         kwargs = {}
-        
+
         for i in range(nargs):
             arg = py_from_lua(runtime, L, i+2)
             if isinstance(arg, _PyArguments):

lupa/tests/test.py

@@ -601,6 +601,74 @@ def test_table_from_table_iter_indirect(self):
         self.assertEqual(list(table2.keys()), [1, 2, 3])
         self.assertEqual(set(table2.values()), set([1, 2, "foo"]))
 
+    def test_table_from_nested_dict(self):
+        data = {"a": {"a": "foo"}, "b": {"b": "bar"}}
+        table = self.lua.table_from(data, recursive=True)
+        self.assertEqual(table["a"]["a"], "foo")
+        self.assertEqual(table["b"]["b"], "bar")
+        self.lua.globals()["data"] = table
+        self.lua.eval("assert(data.a.a=='foo', 'failed')")
+        self.lua.eval("assert(data.b.b=='bar', 'failed')")
+        self.lua.eval("assert(type(data.a)=='table', 'failed, expect table, got '..type(data.a))")
+        self.lua.eval("assert(type(data.b)=='table', 'failed, expect table, got '..type(data.b))")
+        self.lua.execute("""function itertable(table) 
+            for k,v in pairs(table) do 
+                print(k)  
+                if type(v) == "table" then
+                    itertable(v)
+                else
+                    print(v)
+                end  
+            end 
+        end
+        print('\\n')
+        itertable(data)
+        """)
+        del self.lua.globals()["data"]
+
+    def test_table_from_nested_list(self):
+        data = {"a": {"a": "foo"}, "b": [1, 2, 3]}
+        table = self.lua.table_from(data, recursive=True)
+        self.assertEqual(table["a"]["a"], "foo")
+        self.assertEqual(table["b"][1], 1)
+        self.assertEqual(table["b"][2], 2)
+        self.assertEqual(table["b"][3], 3)
+        self.lua.globals()["data"] = table
+        self.lua.eval("assert(data.a.a=='foo', 'failed')")
+        self.lua.eval("assert(#data.b==3, 'failed')")
+        self.lua.eval("assert(type(data.a)=='table', 'failed, expect table, got '..type(data.a))")
+        self.lua.eval("assert(type(data.b)=='table', 'failed, expect table, got '..type(data.b))")
+        self.lua.execute("""function itertable(table) 
+            for k,v in pairs(table) do 
+                print(k)  
+                if type(v) == "table" then
+                    itertable(v)
+                else
+                    print(v)
+                end  
+            end 
+        end
+        print('\\n')
+        itertable(data)
+        """)
+        del self.lua.globals()["data"]
+
+    def test_table_from_nested_list_bad(self):
+        data = {"a": {"a": "foo"}, "b": [1, 2, 3]}
+        table = self.lua.table_from(data, recursive=False) # in this case, lua will get userdata instead of table
+        self.assertEqual(table["a"]["a"], "foo")
+        self.assertEqual(table["b"][0], 1)
+        self.assertEqual(table["b"][1], 2)
+        self.assertEqual(table["b"][2], 3)
+        self.lua.globals()["data"] = table
+
+        def test():
+            self.lua.eval("assert(type(data.a)=='table', 'failed, expect table, got '..type(data.a))")
+            self.lua.eval("assert(type(data.b)=='table', 'failed, expect table, got '..type(data.b))")
+
+        self.assertRaises(lupa.LuaError, test)
+        del self.lua.globals()["data"]
+
     # FIXME: it segfaults
     # def test_table_from_generator_calling_lua_functions(self):
     #     func = self.lua.eval("function (obj) return obj end")