Add a new test of csr sparse matrix creation from non-contiguous tensor

Author: mrkn

cpp/src/arrow/sparse_tensor-test.cc

@@ -293,4 +293,45 @@ TEST(TestSparseCSRMatrix, CreationFromNumericTensor2D) {
   ASSERT_EQ(std::vector<int64_t>({0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}), indices_values);
 }
 
+TEST(TestSparseCSRMatrix, CreationFromNonContiguousTensor) {
+  std::vector<int64_t> shape = {6, 4};
+  std::vector<int64_t> values = {1,  0, 0, 0, 2,  0, 0, 0, 0, 0, 3,  0, 0, 0, 4,  0,
+                                 5,  0, 0, 0, 6,  0, 0, 0, 0, 0, 11, 0, 0, 0, 12, 0,
+                                 13, 0, 0, 0, 14, 0, 0, 0, 0, 0, 15, 0, 0, 0, 16, 0};
+  std::vector<int64_t> strides = {64, 16};
+  std::shared_ptr<Buffer> buffer = Buffer::Wrap(values);
+  Tensor tensor(int64(), buffer, shape, strides);
+  SparseTensorImpl<SparseCSRIndex> st(tensor);
+
+  ASSERT_EQ(12, st.non_zero_length());
+  ASSERT_TRUE(st.is_mutable());
+
+  const int64_t* ptr = reinterpret_cast<const int64_t*>(st.raw_data());
+  for (int i = 0; i < 6; ++i) {
+    ASSERT_EQ(i + 1, ptr[i]);
+  }
+  for (int i = 0; i < 6; ++i) {
+    ASSERT_EQ(i + 11, ptr[i + 6]);
+  }
+
+  const auto& si = internal::checked_cast<const SparseCSRIndex&>(*st.sparse_index());
+  ASSERT_EQ(1, si.indptr()->ndim());
+  ASSERT_EQ(1, si.indices()->ndim());
+
+  const int64_t* indptr_begin = reinterpret_cast<const int64_t*>(si.indptr()->raw_data());
+  std::vector<int64_t> indptr_values(indptr_begin,
+                                     indptr_begin + si.indptr()->shape()[0]);
+
+  ASSERT_EQ(7, indptr_values.size());
+  ASSERT_EQ(std::vector<int64_t>({0, 2, 4, 6, 8, 10, 12}), indptr_values);
+
+  const int64_t* indices_begin =
+      reinterpret_cast<const int64_t*>(si.indices()->raw_data());
+  std::vector<int64_t> indices_values(indices_begin,
+                                      indices_begin + si.indices()->shape()[0]);
+
+  ASSERT_EQ(12, indices_values.size());
+  ASSERT_EQ(std::vector<int64_t>({0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}), indices_values);
+}
+
 }  // namespace arrow