core/pkgs/build-support/trivial-builders/test/writeCBin.nix

/*
  Run with:

      cd nixpkgs
      nix-build -A tests.trivial-builders.writeCBin
*/

{
  lib,
  writeCBin,
  runCommand,
}:
let
  output = "hello";
  pkg = writeCBin "test-script" ''
    #include <stdio.h>
    int main () {
      printf("hello\n");
      return 0;
    }
  '';
in
assert pkg.meta.mainProgram == "test-script";
runCommand "test-writeCBin" { } ''

  echo Testing with getExe...

  target=${lib.getExe pkg}
  expected=${lib.escapeShellArg output}
  got=$("$target")
  if [[ "$got" != "$expected" ]]; then
    echo "wrong output: expected $expected, got $got"
    exit 1
  fi

  echo Testing with makeBinPath...

  PATH="${lib.makeBinPath [ pkg ]}:$PATH"
  got=$(test-script)
  if [[ "$got" != "$expected" ]]; then
    echo "wrong output: expected $expected, got $got"
    exit 1
  fi

  touch $out
''