Merge branch 'enh/colour' into 'master'

Enh/colour

See merge request fsl/fsleyes/props!45

CHANGELOG.rst

@@ -2,6 +2,21 @@ This document contains the ``fsleyes-props`` release history in reverse
 chronological order.
 
 
+1.7.2 (Saturday March 26th 2021)
+--------------------------------
+
+
+Changed
+^^^^^^^
+
+* The :class:`.Color` property type now accepts any value that is accepted by
+  the `matplotlib.to_rgba
+  <https://matplotlib.org/stable/api/_as_gen/matplotlib.colors.to_rgba.html>`_
+  function.
+* Properties of type The :class:`.Int` and :class:`.Real` can be set to
+  ``None`` (unless ``required=True and allowInvalid=False``).
+
+
 1.7.1 (Tuesday March 9th 2021)
 ------------------------------
 

fsleyes_props/properties_types.py

@@ -35,7 +35,8 @@ import os.path as op
 
 from collections import abc
 
-import numpy as np
+import matplotlib.colors as mplcolors
+import numpy             as np
 
 from . import properties        as props
 from . import properties_value  as propvals
@@ -161,6 +162,9 @@ class Number(props.PropertyBase):
         is returned unchanged.
         """
 
+        if value is None:
+            return value
+
         clamped = attributes['clamped']
 
         if not clamped: return value
@@ -186,6 +190,8 @@ class Int(Number):
         """Overrides :meth:`Number.cast`. Casts the given value to an ``int``,
         and then passes the value to :meth:`Number.cast`.
         """
+        if value is None:
+            return value
         return Number.cast(self, instance, attributes, int(value))
 
 
@@ -221,6 +227,8 @@ class Real(Number):
         """Overrides :meth:`Number.cast`. Casts the given value to a ``float``,
         and then passes the value to :meth:`Number.cast`.
         """
+        if value is None:
+            return value
         return Number.cast(self, instance, attributes, float(value))
 
 
@@ -767,8 +775,8 @@ class Colour(props.PropertyBase):
     """A property which represents a RGBA colour, stored as four floating
     point values in the range ``0.0 - 1.0``.
 
-    RGB colours are also accepted - if an RGB colour is provided, the
-    alpha channel is set to 1.0.
+    Any value which can be interpreted by matplotlib as a RGB(A) colour is
+    accepted. If an RGB colour is provided, the alpha channel is set to 1.0.
     """
 
 
@@ -795,14 +803,7 @@ class Colour(props.PropertyBase):
         range ``(0.0 - 1.0)``.
         """
         props.PropertyBase.validate(self, instance, attributes, value)
-
-        if (not isinstance(value, abc.Sequence)) or \
-           (len(value) not in (3, 4)):
-            raise ValueError('Colour must be a sequence of three/four values')
-
-        for v in value:
-            if (v < 0.0) or (v > 1.0):
-                raise ValueError('Colour values must be between 0.0 and 1.0')
+        mplcolors.to_rgba(value)
 
 
     def cast(self, instance, attributes, value):
@@ -812,24 +813,8 @@ class Colour(props.PropertyBase):
         If the alpha channel is not provided, it is set to the current alpha
         value (which defaults to ``1.0``).
         """
-
-        pv = self.getPropVal(instance)
-
-        if pv is not None: currentVal = pv.get()
-        else:              currentVal = self.getAttribute(None, 'default')
-
-        value = [float(v) for v in value]
-
-        if len(value) == 3:
-            value = value + [currentVal[3]]
-
-        value = value[:4]
-
-        for i, v in enumerate(value):
-            if v < 0.0: value[i] = 0.0
-            if v > 1.0: value[i] = 1.0
-
-        return value
+        if value is not None: return mplcolors.to_rgba(value)
+        else:                 return value
 
 
 class ColourMap(props.PropertyBase):

tests/test_property_number.py

@@ -15,6 +15,7 @@ def test_Int():
 
     class MyObj(props.HasProperties):
         unbounded           = props.Int()
+        required            = props.Int(required=True, allowInvalid=False)
         unbounded_default   = props.Int(default=10)
         bounded             = props.Int(minval=0, maxval=10)
         bounded_min         = props.Int(minval=0)
@@ -26,14 +27,17 @@ def test_Int():
 
     obj = MyObj()
 
-    # property, value, expected
 
     assert obj.unbounded_default == 10
 
     with pytest.raises(ValueError): obj.unbounded = ''
     with pytest.raises(ValueError): obj.unbounded = 'abcde'
-    with pytest.raises(TypeError):  obj.unbounded = None
+    with pytest.raises(ValueError): obj.required = None
+
+    obj.unbounded = None
+    obj.required  = 10
 
+    # property, value, expected
     testcases = [
         ('unbounded',         '-999', -999),
         ('unbounded',            '0',    0),