core/pkgs/build-support/trivial-builders/test/write-text-file.nix

/* To run:

       cd nixpkgs
       nix-build -A tests.trivial-builders.writeTextFile

   or to run an individual test case

       cd nixpkgs
       nix-build -A tests.trivial-builders.writeTextFile.foo
*/
{ lib, runCommand, runtimeShell, writeTextFile }:
let
  veryWeirdName =
    ''here's a name with some "bad" characters, like spaces and quotes'';
in lib.recurseIntoAttrs {

  different-exe-name = let
    pkg = writeTextFile {
      name = "bar";
      destination = "/bin/foo";
      executable = true;
      text = ''
        #!${runtimeShell}
        echo hi
      '';
    };
  in assert pkg.meta.mainProgram == "foo";
  assert baseNameOf (lib.getExe pkg) == "foo";
  assert pkg.name == "bar";
  runCommand "test-writeTextFile-different-exe-name" { } ''
    PATH="${lib.makeBinPath [ pkg ]}:$PATH"
    x=$(foo)
    [[ "$x" == hi ]]
    touch $out
  '';

  weird-name = writeTextFile {
    name = "weird-names";
    destination = "/etc/${veryWeirdName}";
    text = "passed!";
    checkPhase = ''
      # intentionally hardcode everything here, to make sure
      # Nix does not mess with file paths

      name="here's a name with some \"bad\" characters, like spaces and quotes"
      fullPath="$out/etc/$name"

      if [ -f "$fullPath" ]; then
        echo "[PASS] File exists!"
      else
        echo "[FAIL] File was not created at expected path!"
        exit 1
      fi

      content=$(<"$fullPath")
      expected="passed!"

      if [ "$content" = "$expected" ]; then
        echo "[PASS] Contents match!"
      else
        echo "[FAIL] File contents don't match!"
        echo "       Expected: $expected"
        echo "       Got:      $content"
        exit 2
      fi
    '';
  };
}