System.err.println("stderr: " + stderr);
                System.err.println("===================================================");

                logs.put(goal, stdout.toString());
                if (exception != null) {
                    throw exception;
                } else {
                    assertEquals(0, exitCode, "OUT:" + stdout + "\nERR:" + stderr);
                }
            }

        }

        public Builder stdOut(OutputStream stdOut) {
            this.stdOut = stdOut;
            return this;
        }

        public Builder stdErr(OutputStream stdErr) {
            this.stdErr = stdErr;
            return this;
        }

        public Builder embedded(boolean embedded) {
            this.embedded = embedded;
            return this;
        }

        final String stdout;
        final String stderr;

        ExecResult(int exitCode, String stdout, String stderr) {
            this.exitCode = exitCode;
            this.stdout = stdout;
            this.stderr = stderr;
        }

        @Override
        public String toString() {
            return "exitCode=" + exitCode + ", stdout=" + summarize(stdout) + ", stderr=" + summarize(stderr);
        }

        private final int code;
        private final String stdout;
        private final String stderr;

        public ExecResult(String[] args, int code, String stdout, String stderr) {
            this.args = args;
            this.code = code;
            this.stdout = stdout;
            this.stderr = stderr;
        }

        @Override
        public String toString() {

            ClassWorld world,
            @Nullable InputStream stdIn,
            @Nullable OutputStream stdOut,
            @Nullable OutputStream stdErr)
            throws IOException {
        return new MavenCling(world).run(args, stdIn, stdOut, stdErr, true);
    }

    public MavenCling() {
        super();
    }

    public MavenCling(ClassWorld classWorld) {
        super(classWorld);
    }

    }

    private record ExecResult(
        int exitCode,
        String stdout,
        String stderr
    ) {
        @Override
        public String toString() {
            return "exitCode=" + exitCode + ", stdout=" + summarize(stdout) + ", stderr=" + summarize(stderr);
        }

        private static String summarize(String s) {
            if (s == null) return "null";

            ClassWorld world,
            @Nullable InputStream stdIn,
            @Nullable OutputStream stdOut,
            @Nullable OutputStream stdErr)
            throws IOException {
        return new MavenUpCling(world).run(args, stdIn, stdOut, stdErr, true);
    }

    public MavenUpCling() {
        super();
    }

    public MavenUpCling(ClassWorld classWorld) {
        super(classWorld);
    }

            ClassWorld world,
            @Nullable InputStream stdIn,
            @Nullable OutputStream stdOut,
            @Nullable OutputStream stdErr)
            throws IOException {
        return new MavenEncCling(world).run(args, stdIn, stdOut, stdErr, true);
    }

    public MavenEncCling() {
        super();
    }

    public MavenEncCling(ClassWorld classWorld) {
        super(classWorld);
    }

            ClassWorld world,
            @Nullable InputStream stdIn,
            @Nullable OutputStream stdOut,
            @Nullable OutputStream stdErr)
            throws IOException {
        return new MavenShellCling(world).run(args, stdIn, stdOut, stdErr, true);
    }

    public MavenShellCling() {
        super();
    }

    public MavenShellCling(ClassWorld classWorld) {
        super(classWorld);

     *
     * @return an {@link Optional} containing the error stream, or empty if not applicable
     */
    @Nonnull
    default Optional<OutputStream> stdErr() {
        return Optional.ofNullable(parserRequest().stdErr());
    }

    /**
     * Returns a list of core extensions from all sources, that were discovered and loaded. Each instance of