added a new 'colorscale_to_colors' method and finished writing all tests

Author: Kully

plotly/colors.py

@@ -230,6 +230,7 @@ def validate_colors(colors):
                         "Whoops! The elements in your colors tuples "
                         "cannot exceed 1.0."
                     )
+    return colors
 
 
 def convert_colors_to_same_type(colors, colortype='rgb'):
@@ -343,7 +344,7 @@ def convert_dict_colors_to_same_type(colors, colortype='rgb'):
 
 def make_colorscale(colors, scale=None):
     """
-    Makes a colorscale from a list of colors and scale
+    Makes a colorscale from a list of colors and a scale
 
     Takes a list of colors and scales and constructs a colorscale based
     on the colors in sequential order. If 'scale' is left empty, a linear-
@@ -354,16 +355,16 @@ def make_colorscale(colors, scale=None):
     """
     colorscale = []
 
+    # validate minimum colors length of 2
+    if len(colors) < 2:
+        raise exceptions.PlotlyError("You must input a list of colors that "
+                                     "has at least two colors.")
+
     if not scale:
         scale_incr = 1./(len(colors) - 1)
         return [[i * scale_incr, color] for i, color in enumerate(colors)]
 
     else:
-        # validate minimum colors length of 2
-        if len(colors) < 2:
-            raise exceptions.PlotlyError("You must input a list of colors "
-                                         "that has at least two colors.")
-
         # validate scale
         if len(colors) != len(scale):
             raise exceptions.PlotlyError("The length of colors and scale "
@@ -504,3 +505,13 @@ def hex_to_rgb(value):
     rgb_section_length = hex_total_length // 3
     return tuple(int(value[i:i + rgb_section_length], 16)
                  for i in range(0, hex_total_length, rgb_section_length))
+
+
+def colorscale_to_colors(colorscale):
+    """
+    Converts a colorscale into a list of colors
+    """
+    color_list = []
+    for color in colorscale:
+        color_list.append(color[1])
+    return color_list

plotly/tests/test_core/test_colors/test_colors.py

@@ -1,41 +1,115 @@
-import math
 from unittest import TestCase
 
 from nose.tools import raises
 import plotly.tools as tls
 from plotly.exceptions import PlotlyError
 import plotly.colors as colors
 
-"""
+
 class TestColors(TestCase):
 
     def test_validate_colors(self):
 
         # test string input
-        color = 'foo'
+        color_string = 'foo'
 
         pattern = ("If your colors variable is a string, it must be a "
                    "Plotly scale, an rgb color or a hex color.")
 
         self.assertRaisesRegexp(PlotlyError, pattern, colors.validate_colors,
-                                color)
+                                color_string)
 
         # test rgb color
-        color2 = 'rgb(265,0,0)'
+        color_string2 = 'rgb(265, 0, 0)'
 
         pattern2 = ("Whoops! The elements in your rgb colors tuples cannot "
                     "exceed 255.0.")
 
         self.assertRaisesRegexp(PlotlyError, pattern2, colors.validate_colors,
-                                color2)
+                                color_string2)
 
         # test tuple color
-
-        color3 = (1.1, 1, 1)
+        color_tuple = (1, 1, 2)
 
         pattern3 = ("Whoops! The elements in your colors tuples cannot "
                     "exceed 1.0.")
 
         self.assertRaisesRegexp(PlotlyError, pattern3, colors.validate_colors,
-                                color3)
-"""
+                                color_tuple)
+
+    def test_convert_colors_to_same_type(self):
+
+        # test string input
+        color_string = 'foo'
+
+        pattern = ("If your colors variable is a string, it must be a "
+                   "Plotly scale, an rgb color or a hex color.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern,
+                                colors.convert_colors_to_same_type,
+                                color_string)
+
+        # test colortype
+        color_tuple = (1, 1, 1)
+        colortype = 2
+
+        pattern2 = ("You must select either rgb or tuple for your colortype "
+                    "variable.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern2,
+                                colors.convert_colors_to_same_type,
+                                color_tuple, colortype)
+
+    def test_convert_dict_colors_to_same_type(self):
+
+        # test colortype
+        color_dict = dict(apple='rgb(1, 1, 1)')
+        colortype = 2
+
+        pattern = ("You must select either rgb or tuple for your colortype "
+                   "variable.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern,
+                                colors.convert_dict_colors_to_same_type,
+                                color_dict, colortype)
+
+    def test_make_colorscale(self):
+
+        # test minimum colors length
+        color_list = [(0, 0, 0)]
+
+        pattern = (
+            "You must input a list of colors that has at least two colors."
+        )
+
+        self.assertRaisesRegexp(PlotlyError, pattern, colors.make_colorscale,
+                                color_list)
+
+        # test length of colors and scale
+        color_list2 = [(0, 0, 0), (1, 1, 1)]
+        scale = [0]
+
+        pattern2 = ("The length of colors and scale must be the same.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern2, colors.make_colorscale,
+                                color_list2, scale)
+
+        # test first and last number of scale
+        scale2 = [0, 2]
+
+        pattern3 = ("The first and last number in scale must be 0.0 and 1.0 "
+                    "respectively.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern3, colors.make_colorscale,
+                                color_list2, scale2)
+
+        # test for strictly increasing scale
+        color_list3 = [(0, 0, 0), (0.5, 0.5, 0.5), (1, 1, 1)]
+        scale3 = [0, 1, 1]
+
+        pattern4 = ("'scale' must be a list that contains an increasing "
+                    "sequence of numbers where the first and last number are"
+                    "0.0 and 1.0 respectively.")
+
+        self.assertRaisesRegexp(PlotlyError, pattern4, colors.make_colorscale,
+                                color_list3, scale3)