Fix BufferView repeating last line for the remainder of the view

test/src/test_BufferView.cc

@@ -682,3 +682,19 @@ TEST(BufferViewTest, scrolls_window_through_a_very_long_single_line_file)
     EXPECT_EQ(9, bv.cursor_screen_row());
     EXPECT_EQ(1009u, **iterator);
 }
+
+TEST(BufferViewTest, shows_only_lines_in_buffer_if_fewer_lines_in_buffer_than_view)
+{
+    auto b = buffer1();
+    auto iterator = b->add_iterator();
+    BufferView bv(b, iterator, Cwd);
+    bv.resize(50, 50);
+    bv.update();
+    int count = 0;
+    for (auto it = bv.vert_iter(); it.is_valid(); it++)
+    {
+        EXPECT_EQ(count, it.row_offset());
+        count++;
+    }
+    EXPECT_EQ(13, count);
+}