require passing a destination directory

docs/changelog/1568.feature.rst

@@ -0,0 +1 @@
+Passing in the virtual environment name/path is now required (no longer defaults to ``venv``) - by :user:`gaborbernat`.

docs/cli_interface.rst

@@ -10,8 +10,8 @@ CLI flags
 
 It modifies the environment variables in a shell to create an isolated Python environment, so you'll need to have a
 shell to run it. You can type in ``virtualenv`` (name of the application) followed by flags that control its
-behaviour. All options have sensible defaults, so you'll get a working virtual environment in a ``venv`` folder even
-if you don't pass any options. The default values for the command line options can be overridden via the
+behaviour. All options have sensible defaults, and there's one required argument: then name/path of the virtual
+environment to create. The default values for the command line options can be overridden via the
 :ref:`conf_file` or :ref:`env_vars`. Environment variables takes priority over the configuration file values
 (``--help`` will show if a default comes from the environment variable as the help message will end in this case
 with environment variables or the configuration file).

src/virtualenv/create/creator.py

@@ -73,7 +73,7 @@ def add_parser_arguments(cls, parser, interpreter, meta):
         :param meta: value as returned by :meth:`can_create`
         """
         parser.add_argument(
-            "dest", help="directory to create virtualenv at", type=cls.validate_dest, default="venv", nargs="?",
+            "dest", help="directory to create virtualenv at", type=cls.validate_dest,
         )
         parser.add_argument(
             "--clear",

tests/unit/config/test_env_var.py

@@ -19,13 +19,13 @@ def empty_conf(tmp_path, monkeypatch):
 
 def test_value_ok(monkeypatch, empty_conf):
     monkeypatch.setenv(str("VIRTUALENV_VERBOSE"), str("5"))
-    result = parse_cli([])
+    result = parse_cli(["venv"])
     assert result.verbosity == 5
 
 
 def test_value_bad(monkeypatch, caplog, empty_conf):
     monkeypatch.setenv(str("VIRTUALENV_VERBOSE"), str("a"))
-    result = parse_cli([])
+    result = parse_cli(["venv"])
     assert result.verbosity == 2
     assert len(caplog.messages) == 1
     assert "env var VIRTUALENV_VERBOSE failed to convert" in caplog.messages[0]