To make sure revision with spaces in them (most likely from repos that
were used with mercurial) as well as revisions with names containing url
encoded characters ("branch%20with%20encoded%spaces").
With a view to making a plugin system in the NixOS Klipper module, this
lets us configure Klipper with extra Python packages, required for
plugins like klippain-shaketune.
Instead of parsing a plain text file with jq, we can make nix-env output
JSON directly, which is significantly faster.
This saves about 8 out of 10 seconds for the combine step.
compare/maintainers.nix needs to access the current checkout to check
attrpaths, but makes the mistake of using lib from that checkout as
well. All other code in ci/ uses the pinned nixpkgs instance, so
maintainers.nix should do so as well.
Previously, `eval.full` organized the results for the supported systems
in a specific layout, i.e. with a folder with one subfolder per system.
Then, `eval.combine` relied on that.
When using `eval.singleSystem` and `eval.combine` directly, the caller
was responsible to recreate the same layout. This is annoying and
error-prone to do, when downloading artifacts from CI to recreate some
steps locally.
With this change, all the artifacts can be downloaded and extracted into
the same folder - because the result from `eval.singleSystem` already
contains the <system-name>/ subfolder.
`env` blocks are a bit like `let` blocks in Nix. They define a few
things, which are then used in the `run` block. The workflows are
considerably easier to read, if those definitions come first, making it
crystal clear where they belong and requiring less visual jumping.
As one of the resident Nixpkgs licensing pedants and reviewer of
several recent changes to this file I think it makes sense to make
the de facto the de jure.
We immediately expected for the other peer to be available in the peer
list, right after startup, but that's racy.
Instead try the pinging multiple times until it succeeds (max 10 times),
then check the list of peers for completion.
