Improve utils shell tests

tests/utils/test_shell.py

@@ -0,0 +1,229 @@
+import os
+
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+from poetry.utils.env import VirtualEnv
+from poetry.utils.shell import WINDOWS
+from poetry.utils.shell import Shell as _Shell
+
+
+@pytest.fixture
+def Shell():
+    _Shell._shell = None
+    return _Shell
+
+
+@pytest.fixture
+def set_SHELL_environment_variable():
+    environ = dict(os.environ)
+
+    VAR = "SHELL" if os.name == "posix" else "COMSPEC"
+    os.environ[VAR] = "/blah/blah/blah/name"
+
+    yield
+
+    os.environ.clear()
+    os.environ.update(environ)
+
+
+@pytest.fixture
+def env():
+    return VirtualEnv(path=Path("/prefix"), base=Path("/base/prefix"))
+
+
+@pytest.fixture
+def MockedSpawn():
+    class _Spawn:
+        def __init__(self, command, args=[], dimensions=None):
+            self.exitstatus = 42
+            self._log = {
+                "setecho": [],
+                "sendline": [],
+                "setwinsize": [],
+                "interact": [],
+                "close": [],
+            }
+
+        def setecho(self, *args, **kwargs):
+            self._log["setecho"].append((args, kwargs))
+
+        def sendline(self, *args, **kwargs):
+            self._log["sendline"].append((args, kwargs))
+
+        def setwinsize(self, *args, **kwargs):
+            self._log["setwinsize"].append((args, kwargs))
+
+        def interact(self, *args, **kwargs):
+            self._log["interact"].append((args, kwargs))
+
+        def close(self, *args, **kwargs):
+            self._log["close"].append((args, kwargs))
+
+    return _Spawn
+
+
+def test_name_and_path_properties(Shell):
+    """
+    Given a Shell object,
+    Check that the name and path propterites
+        match the _name and _path attributes,
+        as well as the values passed in.
+    """
+    s = Shell(name="name", path="path")
+    assert s.name == s._name == "name"
+    assert s.path == s._path == "path"
+
+
+def test_default_shell_is_None(Shell):
+    """
+    Given the Shell class,
+    Check that _shell is None
+    """
+    assert Shell._shell is None
+
+
+def test_get_when__shell_is_not_none(Shell):
+    """
+    Given the Shell class, when _shell is not None,
+    Check that the get class method returns Shell._shell
+    """
+    s = Shell(name="name", path="path")
+    Shell._shell = s
+    assert Shell.get() == s
+
+
+def test_get_when_detect_shell_works(Shell, mocker):
+    """
+    Given the Shell class,
+    When Shell.get() is called, and shellingham.detect_shell()
+        doesn't error.
+    Check that the resulting shell's name and path are as expected,
+        and that Shell._shell is updated.
+    """
+    mocker.patch(
+        "poetry.utils.shell.detect_shell", return_value=("Mocked Name", "Mocked Path")
+    )
+    s = Shell.get()
+    assert s.name == "Mocked Name"
+    assert s.path == "Mocked Path"
+    assert Shell._shell == s
+
+
+def test_get_when_detect_shell_raises_error(
+    Shell, mocker, set_SHELL_environment_variable
+):
+    """
+    Given the Shell Class running on a posix system.
+    When Shell.get() is called, and shellingham.detect_shell()
+        raises an error, but os.environ.get is not None.
+    Check that the resulting shell is as expected.
+    """
+    mocker.patch("poetry.utils.shell.detect_shell", side_effect=RuntimeError)
+
+    s = Shell.get()
+    assert s.name == "name"
+    assert s.path == "/blah/blah/blah/name"
+    assert Shell._shell == s
+
+
+def test_get_when_detect_shell_raises_error_and_os_environ_get_returns_None(
+    Shell, mocker, set_SHELL_environment_variable
+):
+    """
+    Given the Shell Class.
+    When Shell.get() is called, shellingham.detect_shell() raises
+        an error, and os.environ.get returns None (i.e. SHELL or
+        COMSPEC environment variable isn't set).
+    Check that RuntimeError is raised.
+    """
+    mocker.patch("poetry.utils.shell.detect_shell", side_effect=RuntimeError)
+
+    del os.environ["SHELL" if os.name == "posix" else "COMSPEC"]
+
+    excinfo = pytest.raises(RuntimeError, Shell.get)
+    assert "Unable to detect the current shell." in str(excinfo)
+
+
+@pytest.mark.parametrize(
+    "s_name,suffix",
+    [
+        pytest.param("fish", ".fish", id="fish"),
+        pytest.param("csh", ".csh", id="csh"),
+        pytest.param("tcsh", ".csh", id="tcsh"),
+        pytest.param("Anything Else", "", id="Default Case"),
+    ],
+)
+def test__get_activate_script(s_name, suffix, Shell):
+    """
+    Given a Shell,
+    Check that s._get_activate_script() returns the correct script.
+    """
+    s = Shell(name=s_name, path="path")
+    assert s._get_activate_script() == "activate" + suffix
+
+
+@pytest.mark.parametrize(
+    "s_name,command",
+    [
+        pytest.param("fish", "source", id="fish"),
+        pytest.param("csh", "source", id="csh"),
+        pytest.param("tcsh", "source", id="tcsh"),
+        pytest.param("Anything Else", ".", id="Default Case"),
+    ],
+)
+def test__get_source_command(s_name, command, Shell):
+    """
+    Given a Shell,
+    Check that s._get_source_command returns the correct command.
+    """
+    s = Shell(name=s_name, path="path")
+    assert s._get_source_command() == command
+
+
+@pytest.mark.skipif(not WINDOWS, reason="Windows specific path")
+def test_activate_if_windows(env, Shell, mocker):
+    """
+    Given a Shell object on windows,
+    When shell.activate(env) is called,
+    Check that env.execute(shell.path) is called.
+    """
+    s = Shell("name", "path")
+
+    with mock.patch.object(env, "execute", return_value=None) as env_execute:
+        s.activate(env)
+    assert env_execute.called_with("path")
+
+
+@pytest.mark.skipif(WINDOWS, reason="Non-Windows specific path")
+def test_activate_if_not_windows(env, Shell, mocker, MockedSpawn):
+    """
+    Given a Shell object on a non-windows system,
+    When shell.activate(env) is called,
+    Check that the correct methods are called on
+    the mocked object returned by pexpect.spawn()
+    """
+    s = Shell("zsh", "path")
+    spawn = MockedSpawn("command")
+    mocker.patch("pexpect.spawn", return_value=spawn)
+
+    with pytest.raises(SystemExit) as exeinfo:
+        s.activate(env)
+
+    expected = {
+        "sendline": [((". /prefix/bin/activate",), {})],
+        "setwinsize": [],
+        "setecho": [((False,), {})],
+        "interact": [((), {"escape_character": None})],
+        "close": [((), {})],
+    }
+
+    assert spawn._log == expected
+    assert exeinfo.value.code == 42
+
+
+def test___repr__(Shell):
+    s = Shell(name="NAME", path="PATH")
+    assert repr(s) == 'Shell("NAME", "PATH")'