std: align PriorityQueue and ArrayList API-wise

[matklad]

ArrayList uses items slice to store len initialized items, while PriorityQueue stores capacity potentially uninitialized items.

This is a surprising difference in the API that leads to bugs!

tigerbeetle/tigerbeetle#1948

[matklad]

Note: I haven't run the tests locally. I'd love to, but there's a conspicuous lack of a single command that I can just copy-paste to get the tests going at https://github.com/ziglang/zig/wiki/Contributing#testing, and I am not motivated enough at this point to extract that command from the overall build instructions :)

[mochalins]

Note: I haven't run the tests locally. I'd love to, but there's a conspicuous lack of a single command that I can just copy-paste to get the tests going at https://github.com/ziglang/zig/wiki/Contributing#testing, and I am not motivated enough at this point to extract that command from the overall build instructions :)

I'm... not sure I understand how there isn't a single easily copyable command to run the tests. It's at the top of the section you linked here. That aside, the first subsection has an even more easy-to-run local test that you can copy paste...

https://github.com/ziglang/zig/wiki/Contributing#directly-testing-the-standard-library-with-zig-test

[matklad]

I have neither ./stage4/bin/zig nor zig in my path. I understand that I can spend time reading more docs about how to get those, but I am not motivated enough to do that, as, at this point, it's easier to just wait for CI

[rohlem]

@matklad just FYI, I don't think having zig in your PATH is required:
zig abc xyz ... with zig in your PATH should yield the same result as specifying the full path as .../path-to-zig/zig abc xyz ... .
(Just be sure with std testing to test the lib/std of the zig executable you're using, lest you accidentally mix two different versions,
since import("std") will usually pick the one next to zig executable.)

[matklad]

The problem is not PATH per se, but rather the fact that I don’t know which Zig I need (or, rather, which command I need to type to get the right zig without understanding which zig is right one).

To clarify, I know that I personally, if I spend time reading the docs, will be able to get the command to build/download the right version of Zig. I went through this exercise a couple of times already during the past year. It’s just that I remember that being non-trivial (the docs specify like five different ways to do this, and it’s unclear which one I need), and that I’ve already forgot what I’ve learned back then :-)

[andrewrk]

Thanks! Great patch.