Start to wizard pauses (including tests)

Author: dwhswenson

paths_cli/tests/wizard/test_pause.py

@@ -0,0 +1,67 @@
+import pytest
+import time
+from paths_cli.tests.wizard.mock_wizard import mock_wizard
+
+from paths_cli.wizard.pause import *
+
+
+def test_get_pause_style():
+    default_style = PAUSE_STYLES['default']
+    assert get_pause_style() == default_style
+
+
+@pytest.mark.parametrize('input_type', ['string', 'tuple', 'PauseStyle'])
+def test_set_pause_style(input_type):
+    # check that we have the default settings
+    default_style = PAUSE_STYLES['default']
+    test_style = PAUSE_STYLES['testing']
+    input_val = {
+        'string': 'testing',
+        'tuple': tuple(test_style),
+        'PauseStyle': PauseStyle(*test_style)
+    }[input_type]
+    assert input_val is not test_style  # always a different object
+    assert get_pause_style() == default_style
+    set_pause_style(input_val)
+    assert get_pause_style() != default_style
+    assert get_pause_style() == test_style
+    set_pause_style('default')  # explicitly reset default
+
+
+def test_set_pause_bad_name():
+    with pytest.raises(RuntimeError, match="Unknown pause style"):
+        set_pause_style('foo')
+
+    # ensure we didn't break anything for later tests
+    assert get_pause_style() == PAUSE_STYLES['default']
+
+
+def test_pause_style_context():
+    assert get_pause_style() == PAUSE_STYLES['default']
+    with pause_style('testing'):
+        assert get_pause_style() == PAUSE_STYLES['testing']
+    assert get_pause_style() == PAUSE_STYLES['default']
+
+
+def _run_pause_test(func):
+    test_style = PAUSE_STYLES['testing']
+    expected = getattr(test_style, func.__name__)
+    wiz = mock_wizard([])
+    with pause_style(test_style):
+        start = time.time()
+        func(wiz)
+        duration = time.time() - start
+    assert expected <= duration < 1.1 * duration
+    return wiz
+
+
+def test_short():
+    _ = _run_pause_test(short)
+
+
+def test_long():
+    _ = _run_pause_test(long)
+
+
+def test_section():
+    wiz = _run_pause_test(section)

paths_cli/wizard/pause.py

@@ -0,0 +1,72 @@
+import time
+import contextlib
+from collections import namedtuple
+
+PauseStyle = namedtuple("PauseStyle", ['short', 'long', 'section'])
+
+PAUSE_STYLES = {
+    'testing': PauseStyle(0.01, 0.03, 0.05),
+    'default': PauseStyle(0.1, 0.5, 0.5),
+    'nopause': PauseStyle(0.0, 0.0, 0.0),
+}
+
+_PAUSE_STYLE = PAUSE_STYLES['default']
+
+
+@contextlib.contextmanager
+def pause_style(style):
+    """Context manager for pause styles.
+
+    Parameters
+    ----------
+    style : :class:`.PauseStyle`
+        pause style to use within the context
+    """
+    old_style = get_pause_style()
+    try:
+        set_pause_style(style)
+        yield
+    finally:
+        set_pause_style(old_style)
+
+
+def get_pause_style():
+    """Get the current pause style"""
+    global _PAUSE_STYLE
+    return _PAUSE_STYLE
+
+
+def set_pause_style(style):
+    """Set the pause style
+
+    Parameters
+    ----------
+    pause_style : :class:`.PauseStyle` or str
+        pause style to use, can be a string if the style is registered in
+        pause.PAUSE_STYLES
+    """
+    global _PAUSE_STYLE
+    if isinstance(style, str):
+        try:
+            _PAUSE_STYLE = PAUSE_STYLES[style]
+        except KeyError as exc:
+            raise RuntimeError(f"Unknown pause style: '{style}'") from exc
+    else:
+        _PAUSE_STYLE = style
+
+
+def section(wizard):
+    """Section break (pause and possible visual cue).
+    """
+    time.sleep(_PAUSE_STYLE.section)
+    # TODO: have the wizard draw a line?
+
+
+def long(wizard):
+    """Long pause from the wizard"""
+    time.sleep(_PAUSE_STYLE.long)
+
+
+def short(wizard):
+    """Short pause from the wizard"""
+    time.sleep(_PAUSE_STYLE.short)