import json
from pathlib import Path
from click.testing import CliRunner
from docforge.cli.main import cli

def test_mcp_build(cli_runner):
    with cli_runner.isolated_filesystem():
        cwd = Path.cwd()
        pkg = cwd / "testpkg"
        pkg.mkdir()
        (pkg / "__init__.py").write_text("")
        (pkg / "mod.py").write_text("def f(): ...\n")

        out_dir = cwd / "mcp_docs"

        result = cli_runner.invoke(
            cli,
            [
                "build",
                "--mcp",
                "--module",
                "testpkg",
                "--out-dir",
                str(out_dir),
            ],
        )

        assert result.exit_code == 0
        assert (out_dir / "index.json").exists()
        assert (out_dir / "nav.json").exists()
        assert (out_dir / "modules" / "testpkg.mod.json").exists()