Print tox minversion with --print-deps-to

Partially fixes https://github.com/fedora-python/tox-current-env/issues/39

src/tox_current_env/hooks.py

@@ -197,6 +197,14 @@ def tox_testenv_install_deps(venv, action):
         return True
 
 
+def tox_dependencies(config):
+    """Get dependencies of tox itself, 'minversion' config option"""
+    deps = []
+    if config.minversion is not None:
+        deps.append(f"tox >= {config.minversion}")
+    return deps
+
+
 @tox.hookimpl
 def tox_runtest(venv, redirect):
     """If --print-deps-to, prints deps instead of running tests.
@@ -208,6 +216,7 @@ def tox_runtest(venv, redirect):
 
     if config.option.print_deps_to:
         print(
+            *tox_dependencies(config),
             *venv.get_resolved_dependencies(),
             sep="\n",
             file=config.option.print_deps_to,

tests/test_integration.py

@@ -150,6 +150,24 @@ def test_print_deps(toxenv, print_deps_stdout_arg):
     assert result.stdout == expected
 
 
+@pytest.mark.parametrize("toxenv", ["py36", "py37", "py38", "py39"])
+def test_print_deps_with_tox_minversion(projdir, toxenv, print_deps_stdout_arg):
+    with modify_config(projdir / 'tox.ini') as config:
+        config["tox"]["minversion"] = "3.13"
+    result = tox("-e", toxenv, print_deps_stdout_arg)
+    expected = textwrap.dedent(
+        f"""
+        tox >= 3.13
+        six
+        py
+        ___________________________________ summary ____________________________________
+          {toxenv}: commands succeeded
+          congratulations :)
+        """
+    ).lstrip()
+    assert result.stdout == expected
+
+
 @pytest.mark.parametrize("toxenv", ["py36", "py37", "py38", "py39"])
 def test_print_extras(toxenv, print_extras_stdout_arg):
     result = tox("-e", toxenv, print_extras_stdout_arg)