Similar to `vector/_first`, this didn't check for the empty vector case, so I've changed it to return `:ignore-instruction` in that case.
There's a lot of duplication between `_first` and `_last`, which makes me think there's some refactoring opportunities.
This adds test.check tests for `vector/_last`. This is _really_ similar to `vector/_first` (and the other vector tests), so I think there are definitely ways to extract common logic from these.
The original version just used the built-in `first`, which returns `nil` if you give it an empty collection, which is almost certainly not a useful behavior.
This changes it to return `:ignore-instruction` if the vector is empty, thereby leaving all the stacks unchanged.
`make-instruction` will ignore any instructions that return `:ignore-instruction`. This allows instructions to be skipped without consuming their arguments.
There were two independent bugs in `vector/_subvec` that were turned up by our `test.check` testing.
The first was that the order of the arguments was wrong and `stop-raw` and `start-raw` were flipped.
The second was that `stop` wasn't max'ed with 0, which meant it could sometimes be negative, leading to an `IndexOutOfBoundsException`.
This is a start on using `test.check` to write tests for the vector instructions. We currently have tests for:
* `vector/_emptyvector`
* `vector/_indexof`
* `vector/_subvec`
There are _lots_ of other functions still to be tested.
This did reveal errors in `vector/_subvec`, which will be addressed in the next commit.
We used macros to make it easy to generate tests for each of the four vector types; this should be extensible to additional vector types in the future if needed.
The `random-int` function in both `number-io` and `smallest` subtracted a floating point value (`100.0`), which means they were both _actually_ returning a float instead of an int.
This removes both of the ".0"s so that they return integers as advertised.
