message: Add tests for ArrayView::empty()
diff: @@ -110,6 +110,7 @@ AXOM_TYPED_TEST(core_array_for_all, auto_ArrayView)
  // Modify array using lambda and ArrayView
  auto arr_view = arr.view();
  + EXPECT_FALSE(arr_view.empty());
  axom::for_all<ExecSpace>(
  N,
  AXOM_LAMBDA(axom::IndexType idx) { arr_view[idx] = N - idx; });
  @@ -126,6 +127,11 @@ AXOM_TYPED_TEST(core_array_for_all, auto_ArrayView)
  {
  EXPECT_EQ(localArr[i], N - i);
  }
  +
  + // Empty the array and create a view from it. ArrayView::empty() should return true.
  + arr.clear();
  + auto empty_view = arr.view();
  + EXPECT_TRUE(empty_view.empty());
  }
  //------------------------------------------------------------------------------
  @@ -149,6 +155,7 @@ AXOM_TYPED_TEST(core_array_for_all, auto_ArrayView_const)
  // Then copy it over to the device
  KernelArray kernelSource = source;
  auto kernelSourceView = kernelSource.view();
  + EXPECT_FALSE(kernelSourceView.empty());
  // First, modify array using lambda and KernelArray::ArrayView operator[] const
  auto arrData = arr.data();
  @@ -177,6 +184,7 @@ AXOM_TYPED_TEST(core_array_for_all, auto_ArrayView_const)
  const KernelArray& kernelSourceCref = kernelSource;
  auto kernelSourceConstView = kernelSourceCref.view();
  + EXPECT_FALSE(kernelSourceConstView.empty());
  axom::for_all<ExecSpace>(
  N,
  @@ -196,6 +204,11 @@ AXOM_TYPED_TEST(core_array_for_all, auto_ArrayView_const)
  {
  EXPECT_EQ(localArr[i], N - i);
  }
  +
  + // Empty the array and create a view from it. ArrayView::empty() should return true.
  + arr.clear();
  + auto empty_view = arr.view();
  + EXPECT_TRUE(empty_view.empty());
  }
  //------------------------------------------------------------------------------
  