[Bugfix] Fix visit_attrs error if its function pointer is equal to nu…

…llptr (#8920)

* fix visit_attrs equals nullptr on python container object

* add a test a for python container object about function dir and getattr

* change test_ir_container.py to the pytest style

* update the style to fix ci error

* update the style of ir container to fix ci error

python/tvm/ir/container.py

@@ -38,6 +38,16 @@ def __getitem__(self, idx):
     def __len__(self):
         return _ffi_api.ArraySize(self)
 
+    def __dir__(self):
+        return sorted(dir(self.__class__) + ["type_key"])
+
+    def __getattr__(self, name):
+        if name == "handle":
+            raise AttributeError("handle is not set")
+        if name == "type_key":
+            return super().__getattr__(name)
+        raise AttributeError("%s has no attribute %s" % (str(type(self)), name))
+
 
 @tvm._ffi.register_object
 class Map(Object):
@@ -59,6 +69,16 @@ def __iter__(self):
         for i in range(len(self)):
             yield akvs[i * 2]
 
+    def __dir__(self):
+        return sorted(dir(self.__class__) + ["type_key"])
+
+    def __getattr__(self, name):
+        if name == "handle":
+            raise AttributeError("handle is not set")
+        if name == "type_key":
+            return super().__getattr__(name)
+        raise AttributeError("%s has no attribute %s" % (str(type(self)), name))
+
     def keys(self):
         return iter(self)
 

tests/python/unittest/test_ir_container.py

@@ -14,6 +14,7 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
+import pytest
 import tvm
 from tvm import te
 import numpy as np
@@ -34,6 +35,17 @@ def test_array_save_load_json():
     assert a_loaded[1].value == 2
 
 
+def test_dir_array():
+    a = tvm.runtime.convert([1, 2, 3])
+    assert dir(a)
+
+
+def test_getattr_array():
+    a = tvm.runtime.convert([1, 2, 3])
+    assert getattr(a, "type_key") == "Array"
+    assert not hasattr(a, "test_key")
+
+
 def test_map():
     a = te.var("a")
     b = te.var("b")
@@ -70,6 +82,21 @@ def test_map_save_load_json():
     assert dd == {"a": 2, "b": 3}
 
 
+def test_dir_map():
+    a = te.var("a")
+    b = te.var("b")
+    amap = tvm.runtime.convert({a: 2, b: 3})
+    assert dir(amap)
+
+
+def test_getattr_map():
+    a = te.var("a")
+    b = te.var("b")
+    amap = tvm.runtime.convert({a: 2, b: 3})
+    assert getattr(amap, "type_key") == "Map"
+    assert not hasattr(amap, "test_key")
+
+
 def test_in_container():
     arr = tvm.runtime.convert(["a", "b", "c"])
     assert "a" in arr
@@ -86,10 +113,4 @@ def test_ndarray_container():
 
 
 if __name__ == "__main__":
-    test_str_map()
-    test_array()
-    test_map()
-    test_array_save_load_json()
-    test_map_save_load_json()
-    test_in_container()
-    test_ndarray_container()
+    pytest.main([__file__])