veloren/nix/utils.nix
2022-09-02 21:13:57 +03:00

67 lines
2.0 KiB
Nix

{pkgs}: {
isGitLfsSetup = checkFile: let
gitLfsCheckOutput = builtins.readFile (pkgs.runCommand "gitLfsCheck" {} ''
result="$(${pkgs.file}/bin/file --mime-type ${checkFile})"
(if [ "$result" = "${checkFile}: image/jpeg" ]; then printf "0"; else printf "1"; fi) > $out
'');
in
if gitLfsCheckOutput == "0"
then true
else
throw ''
Git Large File Storage (`git-lfs`) has not been set up correctly.
Most common reasons:
- `git-lfs` was not installed before cloning this repository.
- This repository was not cloned from the primary GitLab mirror.
- The GitHub mirror does not support LFS.
See the book at https://book.veloren.net/ for details.
Run `nix-shell -p git git-lfs --run "git lfs install --local && git lfs fetch && git lfs checkout"`
or `nix shell nixpkgs#git-lfs nixpkgs#git -c sh -c "git lfs install --local && git lfs fetch && git lfs checkout"`.
'';
# Format number of seconds in the Unix epoch as %Y-%m-%d-%H:%M.
dateTimeFormat = t: let
rem = x: y: x - x / y * y;
days = t / 86400;
secondsInDay = rem t 86400;
hours = secondsInDay / 3600;
minutes = (rem secondsInDay 3600) / 60;
seconds = rem t 60;
# Courtesy of https://stackoverflow.com/a/32158604.
z = days + 719468;
era =
(
if z >= 0
then z
else z - 146096
)
/ 146097;
doe = z - era * 146097;
yoe = (doe - doe / 1460 + doe / 36524 - doe / 146096) / 365;
y = yoe + era * 400;
doy = doe - (365 * yoe + yoe / 4 - yoe / 100);
mp = (5 * doy + 2) / 153;
d = doy - (153 * mp + 2) / 5 + 1;
m =
mp
+ (
if mp < 10
then 3
else -9
);
y' =
y
+ (
if m <= 2
then 1
else 0
);
pad = s:
if builtins.stringLength s < 2
then "0" + s
else s;
in "${toString y'}-${pad (toString m)}-${pad (toString d)}-${pad (toString hours)}:${pad (toString minutes)}";
}