explicit import testing (#956)

* explicit import testing

* Enable init api for extension modules

python/tvm/_ffi/function.py

@@ -280,15 +280,23 @@ def _get_api(f):
         return flocal(*args)
     return my_api_func
 
-def _init_api(namespace):
+def _init_api(namespace, target_module_name=None):
     """Initialize api for a given module name
 
-    mod : str
-       The name of the module.
+    namespace : str
+       The namespace of the source registry
+
+    target_module_name : str
+       The target module name if different from namespace
     """
-    assert namespace.startswith("tvm.")
+    target_module_name = (
+        target_module_name if target_module_name else namespace)
+    if namespace.startswith("tvm."):
         prefix = namespace[4:]
-    _init_api_prefix(namespace, prefix)
+        _init_api_prefix(target_module_name, namespace[4:])
+    else:
+        _init_api_prefix(target_module_name, namespace)
+
 
 def _init_api_prefix(module_name, prefix):
     module = sys.modules[module_name]

topi/tests/python/test_topi_conv2d.py

@@ -3,6 +3,7 @@ import os
 import numpy as np
 import tvm
 import topi
+import topi.testing
 from tvm.contrib.pickle_memoize import memoize
 from topi.util import get_const_tuple
 

topi/tests/python/test_topi_conv2d_hwcn.py

@@ -3,6 +3,7 @@ import os
 import numpy as np
 import tvm
 import topi
+import topi.testing
 from tvm.contrib.pickle_memoize import memoize
 from topi.util import get_const_tuple
 

topi/tests/python/test_topi_conv2d_nhwc.py

@@ -3,6 +3,7 @@ import os
 import numpy as np
 import tvm
 import topi
+import topi.testing
 from tvm.contrib.pickle_memoize import memoize
 from topi.util import get_const_tuple
 

topi/tests/python/test_topi_conv2d_transpose_nchw.py

@@ -2,6 +2,7 @@
 import numpy as np
 import tvm
 import topi
+import topi.testing
 from tvm.contrib.pickle_memoize import memoize
 from topi.util import get_const_tuple
 

topi/tests/python/test_topi_dense.py

@@ -2,6 +2,7 @@
 import numpy as np
 import tvm
 import topi
+import topi.testing
 from topi.util import get_const_tuple
 from tvm.contrib.pickle_memoize import memoize
 

topi/tests/python/test_topi_depthwise_conv2d.py

 import tvm
 import topi
+import topi.testing
 import numpy as np
 from scipy import signal
 from topi.util import get_const_tuple

topi/tests/python/test_topi_depthwise_conv2d_back_input.py

@@ -5,6 +5,7 @@ from tvm.contrib.pickle_memoize import memoize
 from scipy import signal
 from topi.util import get_const_tuple
 from topi.nn.util import get_pad_tuple
+import topi.testing
 from topi.cuda.depthwise_conv2d import schedule_depthwise_conv2d_backward_input_nhwc
 
 

topi/tests/python/test_topi_depthwise_conv2d_back_weight.py

 import tvm
 import topi
+import topi.testing
 import numpy as np
 from tvm.contrib.pickle_memoize import memoize
 from scipy import signal

topi/tests/python/test_topi_math.py

 import numpy as np
 import tvm
 import topi
+import topi.testing
 from topi import util