import pytest
from chordparser.analysers.chords_analyser import ChordAnalyser
from chordparser.editors.chords_editor import ChordEditor
from chordparser.editors.keys_editor import KeyEditor
from chordparser.editors.notes_editor import NoteEditor
from chordparser.editors.scales_editor import ScaleEditor
NE = NoteEditor()
KE = KeyEditor()
SE = ScaleEditor()
CE = ChordEditor()
CA = ChordAnalyser()
@pytest.mark.parametrize(
"chord, mode, incl_submodes, result", [
("C", "major", True, [('I', 'major', None)]),
("C7", "major", False, [('I7', 'major', None)]),
("Cm", "minor", False, [('i', 'minor', 'natural')]),
("Cm", "minor", True, [('i', 'minor', 'natural'), ('i', 'minor', 'harmonic'), ('i', 'minor', 'melodic')]),
]
)
def test_diatonic(chord, mode, incl_submodes, result):
c = CE.create_chord(chord)
s = SE.create_scale("C", mode)
assert CA.analyse_diatonic(c, s, incl_submodes) == result
@pytest.mark.parametrize(
class ScaleEditor:
"""A `Scale` editor that can create and change `Scales`.
The `ScaleEditor` class can create a `Scale` from a `Key` or a `Key`'s notation. It can change the `Scale` by specifying a different `Key` it is based on.
"""
_KE = KeyEditor()
def create_scale(self, value, *args, **kwargs):
"""Create a `Scale`.
Specify either a `Key` or the parameters necessary to create a `Key`.
Parameters
----------
value
Either a `Key` or the first parameter for creating a `Key` (i.e. the `root`).
*args : iterable
The parameters for creating a `Key`.
**kwargs : dict
The keyword parameters for creating a `Key`.
Returns
-------
Scale
The created `Scale`.
See Also
--------
chordparser.KeyEditor.create_key : See the necessary parameters for creating a `Key`.
Examples
--------
>>> SE = ScaleEditor()
>>> KE = KeyEditor()
>>> c_key = KE.create_key("C", "minor")
>>> SE.create_scale(c_key)
C natural minor scale
>>> SE.create_scale("C", "major")
C major scale
"""
if not isinstance(value, Key):
key = self._KE.create_key(value, *args, **kwargs)
else:
key = value
return Scale(key)
def change_scale(self, scale, *args, inplace=True, **kwargs):
"""Change a `Scale` based on its `Key`.
The parameters accepted are the same parameters accepted for changing a `Key`: the `root`, `mode` and `submode`. The `root` must be a valid `Note` notation if type `str`. The `submode` refers to the different types of 'minor'/ 'aeolian' mode, i.e. 'natural', 'harmonic' and 'melodic'. Hence, other than the 'minor'/ 'aeolian' `mode`, the `submode` must be None.
Parameters
----------
scale : Scale
The `Scale` which key you want to change.
*args : iterable
The parameters for changing the `Scale`'s `Key`.
inplace : boolean, Optional
Selector to change the current `Scale` or to return a new `Scale`. Default True when optional.
**kwargs : dict
The keyword parameters for changing the `Scale`'s `Key`.
Returns
-------
Scale
The `Scale` with the new `Key`.
Examples
--------
>>> SE = ScaleEditor()
>>> c = SE.create_scale("C", "major")
>>> SE.change_scale(c, "D", "lydian")
D lydian scale
>>> SE.change_scale(c, "E", "dorian", inplace=False)
E dorian scale
>>> c
D lydian scale
"""
if not inplace:
scale = self.create_scale(scale.key)
self._KE.change_key(scale.key, *args, **kwargs)
scale.build()
return scale