For the test for fillcells, what exactly are we requiring? Is it that the correct fraction of cells are alive? Or is it that they are uniformly filled? Also, do you specifically want to test multiple fractions, multiple num_cells, or both? I'm just not sure which REQUIRE statements would make sense here. For example, if you ask it to fill 70% of cells but the num_cells is small, e.g. 5, isn't it impossible to fill exactly 70% of the cells? In these cases, should there be a tolerance threshold?
It is okay to restrict yourself in the tests to cases that fit exactly here
(mostly because there's no documentation on how the approximation works otherwise, so you cannot know what the tolerance should be - this is a deficiency of the documentation of this code - mea culpa).
Yes, various (small) sizes of num_cells and a few fractions should be included.
Thanks! In that case do we need to write a function to calculate the number of alive cells in a given Cells element? Or is there an easier way to do this?