core/pkgs/build-support/fetchgitlocal/default.nix
2024-05-13 22:24:10 +01:00

43 lines
1.1 KiB
Nix

{ runCommand, git, lib }:
lib.makeOverridable (src:
let
srcStr = toString src;
# Adds the current directory (respecting ignored files) to the git store, and returns the hash
gitHashFile = runCommand "put-in-git" {
nativeBuildInputs = [ git ];
dummy = builtins.currentTime; # impure, do every time
preferLocalBuild = true;
} ''
cd ${srcStr}
DOT_GIT=$(git rev-parse --resolve-git-dir .git) # path to repo
cp $DOT_GIT/index $DOT_GIT/index-user # backup index
git reset # reset index
git add . # add current directory
# hash of current directory
# remove trailing newline
git rev-parse $(git write-tree) \
| tr -d '\n' > $out
mv $DOT_GIT/index-user $DOT_GIT/index # restore index
'';
gitHash = builtins.readFile gitHashFile; # cache against git hash
nixPath = runCommand "put-in-nix" {
nativeBuildInputs = [ git ];
preferLocalBuild = true;
} ''
mkdir $out
# dump tar of *current directory* at given revision
git -C ${srcStr} archive --format=tar ${gitHash} \
| tar xf - -C $out
'';
in nixPath)