toCommandLine

lib.cli.toCommandLine

Docs pulled from | This Revision | 4 days ago

Converts an attribute set into a list of command line options.

toCommandLine returns a list of string arguments.

Inputs

optionFormat: The option format that describes how options and their arguments should be formatted.
attrs: The attributes to transform into arguments.

Examples

`lib.cli.toCommandLine` usage example

let
  optionFormat = optionName: {
    option = "-${optionName}";
    sep = "=";
    explicitBool = true;
  };
in lib.cli.toCommandLine optionFormat {
  v = true;
  verbose = [true true false null];
  i = ".bak";
  testsuite = ["unit" "integration"];
  e = ["s/a/b/" "s/b/c/"];
  n = false;
  data = builtins.toJSON {id = 0;};
}
=> [
  "-data={\"id\":0}"
  "-e=s/a/b/"
  "-e=s/b/c/"
  "-i=.bak"
  "-n=false"
  "-testsuite=unit"
  "-testsuite=integration"
  "-v=true"
  "-verbose=true"
  "-verbose=true"
  "-verbose=false"
]

Noogle detected

Implementation

The following is the current implementation of this function.

toCommandLine =
    optionFormat: attrs:
    let
      handlePair =
        k: v:
        if k == "" then
          lib.throw "lib.cli.toCommandLine only accepts non-empty option names."
        else if builtins.isList v then
          builtins.concatMap (handleOption k) v
        else
          handleOption k v;

      handleOption = k: renderOption (optionFormat k) k;

      renderOption =
        {
          option,
          sep,
          explicitBool,
          formatArg ? lib.generators.mkValueStringDefault { },
        }:
        k: v:
        if v == null || (!explicitBool && v == false) then
          [ ]
        else if !explicitBool && v == true then
          [ option ]
        else
          let
            arg = formatArg v;
          in
          if sep != null then
            [ "${option}${sep}${arg}" ]
          else
            [
              option
              arg
            ];
    in
    builtins.concatLists (lib.mapAttrsToList handlePair attrs);