para: add Paragraph.alignment setter

docx/oxml/text.py

@@ -59,6 +59,11 @@ def alignment(self):
             return None
         return pPr.alignment
 
+    @alignment.setter
+    def alignment(self, value):
+        pPr = self.get_or_add_pPr()
+        pPr.alignment = value
+
     def clear_content(self):
         """
         Remove all child elements, except the ``<w:pPr>`` element if present.
@@ -132,6 +137,14 @@ def alignment(self):
             return None
         return jc.val
 
+    @alignment.setter
+    def alignment(self, value):
+        if value is None:
+            self._remove_jc()
+            return
+        jc = self.get_or_add_jc()
+        jc.val = value
+
     @property
     def style(self):
         """

docx/text.py

@@ -86,6 +86,10 @@ def alignment(self):
         """
         return self._p.alignment
 
+    @alignment.setter
+    def alignment(self, value):
+        self._p.alignment = value
+
     def clear(self):
         """
         Return this same paragraph after removing all its content.

features/par-alignment-prop.feature

@@ -4,7 +4,6 @@ Feature: Get or set paragraph alignment
   I need a read/write alignment property on paragraph objects
 
 
-  @wip
   Scenario Outline: Get paragraph alignment
     Given a paragraph having <align-type> alignment
      Then the paragraph alignment property value is <align-value>

tests/test_text.py

@@ -46,6 +46,11 @@ def it_knows_its_alignment_value(self, alignment_get_fixture):
         paragraph, expected_value = alignment_get_fixture
         assert paragraph.alignment == expected_value
 
+    def it_can_change_its_alignment_value(self, alignment_set_fixture):
+        paragraph, value, expected_xml = alignment_set_fixture
+        paragraph.alignment = value
+        assert paragraph._p.xml == expected_xml
+
     def it_knows_its_paragraph_style(self):
         cases = (
             (Mock(name='p_elm', style='foobar'), 'foobar'),
@@ -120,6 +125,31 @@ def alignment_get_fixture(self, request):
         paragraph = Paragraph(p)
         return paragraph, expected_alignment_value
 
+    @pytest.fixture(params=[
+        ('left', WD_ALIGN_PARAGRAPH.CENTER, 'center'),
+        ('left', None,                      None),
+        (None,   WD_ALIGN_PARAGRAPH.LEFT,   'left'),
+        (None,   None,                      None),
+    ])
+    def alignment_set_fixture(self, request):
+        initial_jc_val, new_alignment_value, expected_jc_val = request.param
+        # paragraph --------------------
+        p_bldr = a_p().with_nsdecls()
+        if initial_jc_val is not None:
+            p_bldr.with_child(
+                a_pPr().with_child(
+                    a_jc().with_val(initial_jc_val))
+            )
+        p = p_bldr.element
+        paragraph = Paragraph(p)
+        # expected_xml -----------------
+        pPr_bldr = a_pPr()
+        if expected_jc_val is not None:
+            pPr_bldr.with_child(a_jc().with_val(expected_jc_val))
+        p_bldr = a_p().with_nsdecls().with_child(pPr_bldr)
+        expected_xml = p_bldr.xml()
+        return paragraph, new_alignment_value, expected_xml
+
     @pytest.fixture
     def clear_fixture(self, request):
         """