[BACKPORT] Support creating tensor from list of tensors (#426) (#429)

mars/tensor/expressions/datasource/array.py

@@ -129,7 +129,7 @@ def tensor(data, dtype=None, chunk_size=None, gpu=None, sparse=False):
         if dtype is not None and data.dtype != dtype:
             return data.astype(dtype)
         return data
-    elif isinstance(data, tuple) and all(isinstance(d, TENSOR_TYPE) for d in data):
+    elif isinstance(data, (tuple, list)) and all(isinstance(d, TENSOR_TYPE) for d in data):
         from ..merge import stack
 
         data = stack(data)

mars/tensor/expressions/tests/test_datasource.py

@@ -23,10 +23,20 @@
     tiledb = None
 
 from mars.tests.core import TestBase
-from mars.tensor.expressions.datasource import fromtiledb, TensorTileDBDataSource
+from mars.tensor.expressions.datasource import array, fromtiledb, TensorTileDBDataSource
 
 
 class Test(TestBase):
+    def testFromArray(self):
+        x = array([1, 2, 3])
+        self.assertEqual(x.shape, (3,))
+
+        y = array([x, x])
+        self.assertEqual(y.shape, (2, 3))
+
+        z = array((x, x, x))
+        self.assertEqual(z.shape, (3, 3))
+
     @unittest.skipIf(tiledb is None, 'TileDB not installed')
     def testFromTileDB(self):
         ctx = tiledb.Ctx()