misc: add getlist filter compatibility for block field (#45394)

tests/test_formdata.py

@@ -2311,3 +2311,6 @@ def test_block_variables(pub, blocks_feature):
 
     tmpl = Template('{{ form_var_block|length }}')
     assert tmpl.render(context) == '2'
+
+    tmpl = Template('{% for foo in form_var_block|getlist:"foo" %}/{{ foo }}{% endfor %}')
+    assert tmpl.render(context) == '/foo/foo2'

wcs/qommon/templatetags/qommon.py

@@ -63,6 +63,11 @@ def get(mapping, key):
     return mapping[key]
 
 
+@register.filter
+def getlist(mapping, key):
+    return mapping.getlist(key)
+
+
 @register.filter
 def startswith(string, substring):
     return string and force_text(string).startswith(force_text(substring))

wcs/variables.py

@@ -890,6 +890,15 @@ class LazyFieldVarBlock(LazyFieldVar):
         for i in range(len(data)):
             yield self[i]
 
+    def getlist(self, key):
+        # called by |getlist filter
+        for field in self._field.block.fields:
+            if field.varname == key:
+                break
+        else:
+            raise AttributeError('No such attribute %r' % key)
+        return [data.get(field.id) for data in self._formdata.data.get(self._field.id)['data']]
+
 
 class LazyUser(object):
     def __init__(self, user):