lib.fileset: file set functions



toSource :: {
  root :: Path,
  fileset :: FileSet,
} -> SourceLike

Add the local files contained in fileset to the store as a single store path rooted at root.

The result is the store path as a string-like value, making it usable e.g. as the src of a derivation, or in string interpolation:

stdenv.mkDerivation {
  src = lib.fileset.toSource { ... };
  # ...

The name of the store path is always source.

structured function argument

: root

(required) The local directory path that will correspond to the root of the resulting store path. Paths in strings, including Nix store paths, cannot be passed as root. root has to be a directory.


Changing root only affects the directory structure of the resulting store path, it does not change which files are added to the store. The only way to change which files get added to the store is by changing the fileset attribute.


(required) The file set whose files to import into the store. Currently the only way to construct file sets is using implicit coercion from paths. If a directory does not recursively contain any file, it is omitted from the store path contents.


lib.fileset.toSource usage example

# Import the current directory into the store but only include files under ./src
toSource { root = ./.; fileset = ./src; }
=> "/nix/store/...-source"

# The file set coerced from path ./bar could contain files outside the root ./foo, which is not allowed
toSource { root = ./foo; fileset = ./bar; }
=> <error>

# The root has to be a local filesystem path
toSource { root = "/nix/store/...-source"; fileset = ./.; }
=> <error>

Located at lib/fileset/default.nix:66 in <nixpkgs>.