Display source change (issue #74)

weblate/html/translate.html

@@ -61,6 +61,12 @@
 <th class="source">{% trans "Source" %}</th>
 <td class="translatetext">{{ unit.source|fmttranslation }}</td>
 </tr>
+{% if unit.previous_source %}
+<tr>
+<th>{% trans "Source change" %}</th>
+<td>{{ unit.previous_source|fmtsourcediff:unit }}</td>
+</tr>
+{% endif %}
 {% if unit.context %}
 <tr>
 <th>{% trans "Context" %}</th>

weblate/trans/templatetags/translations.py

@@ -126,6 +126,15 @@ def fmttranslationdiff(value, other):
     return fmttranslation(value, other.translation.language, other.target)
 
 
+@register.filter
+@stringfilter
+def fmtsourcediff(value, other):
+    '''
+    Formats diff between two sources.
+    '''
+    return fmttranslation(other.source, diff=value)
+
+
 @register.filter
 @stringfilter
 def site_title(value):