font: add Font.highlight_color setter

Author: DKWoods

docx/oxml/text/font.py

@@ -109,6 +109,14 @@ def highlight_val(self):
             return None
         return highlight.val
 
+    @highlight_val.setter
+    def highlight_val(self, value):
+        if value is None:
+            self._remove_highlight()
+            return
+        highlight = self.get_or_add_highlight()
+        highlight.val = value
+
     @property
     def rFonts_ascii(self):
         """

docx/text/font.py

@@ -136,6 +136,11 @@ def highlight_color(self):
             return None
         return rPr.highlight_val
 
+    @highlight_color.setter
+    def highlight_color(self, value):
+        rPr = self._element.get_or_add_rPr()
+        rPr.highlight_val = value
+
     @property
     def italic(self):
         """

features/txt-font-props.feature

@@ -15,7 +15,6 @@ Feature: Get or set font properties
       | bright green    | BRIGHT_GREEN |
 
 
-  @wip
   Scenario Outline: Set highlight color
     Given a font having <color> highlighting
      When I assign <value> to font.highlight_color

tests/text/test_font.py

@@ -85,6 +85,11 @@ def it_knows_its_highlight_color(self, highlight_get_fixture):
         font, expected_value = highlight_get_fixture
         assert font.highlight_color is expected_value
 
+    def it_can_change_its_highlight_color(self, highlight_set_fixture):
+        font, highlight_color, expected_xml = highlight_set_fixture
+        font.highlight_color = highlight_color
+        assert font._element.xml == expected_xml
+
     # fixtures -------------------------------------------------------
 
     @pytest.fixture(params=[
@@ -189,6 +194,26 @@ def highlight_get_fixture(self, request):
         font = Font(element(r_cxml), None)
         return font, expected_value
 
+    @pytest.fixture(params=[
+        ('w:r',                                 WD_COLOR.AUTO,
+         'w:r/w:rPr/w:highlight{w:val=default}'),
+        ('w:r/w:rPr',                           WD_COLOR.BRIGHT_GREEN,
+         'w:r/w:rPr/w:highlight{w:val=green}'),
+        ('w:r/w:rPr/w:highlight{w:val=green}',  WD_COLOR.YELLOW,
+         'w:r/w:rPr/w:highlight{w:val=yellow}'),
+        ('w:r/w:rPr/w:highlight{w:val=yellow}', None,
+         'w:r/w:rPr'),
+        ('w:r/w:rPr',                           None,
+         'w:r/w:rPr'),
+        ('w:r',                                 None,
+         'w:r/w:rPr'),
+    ])
+    def highlight_set_fixture(self, request):
+        r_cxml, value, expected_cxml = request.param
+        font = Font(element(r_cxml), None)
+        expected_xml = xml(expected_cxml)
+        return font, value, expected_xml
+
     @pytest.fixture(params=[
         ('w:r',                               None),
         ('w:r/w:rPr',                         None),