# HG changeset patch
# User cmlenz
# Date 1156258364 0
# Node ID 95c3813a00dec3024c4edf76a1939a9c5b7e7651
# Parent  181d292eafa2ed62e7fe5a9dbf3040abbb9e97b9
Fix for #34: `py:def` macros can now be invoked from within expressions in attribute values.

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -33,6 +33,8 @@
    (ticket #31).
  * Expressions in templates can now span multiple lines if they are enclosed
    in curly braces.
+ * py:def macros can now be invoked from within expressions inside attribute
+   values (ticket #34).
 
 
 Version 0.1
diff --git a/markup/template.py b/markup/template.py
--- a/markup/template.py
+++ b/markup/template.py
@@ -910,12 +910,11 @@
                         value = substream
                     else:
                         values = []
-                        for subkind, subdata, subpos in substream:
-                            if subkind is EXPR:
-                                values.append(subdata.evaluate(ctxt))
-                            else:
+                        for subkind, subdata, subpos in self._eval(substream,
+                                                                   ctxt):
+                            if subkind is TEXT:
                                 values.append(subdata)
-                        value = [unicode(x) for x in values if x is not None]
+                        value = [x for x in values if x is not None]
                         if not value:
                             continue
                     new_attrib.append((name, u''.join(value)))
diff --git a/markup/tests/template.py b/markup/tests/template.py
--- a/markup/tests/template.py
+++ b/markup/tests/template.py
@@ -261,6 +261,24 @@
           foo
         </doc>""", str(tmpl.generate()))
 
+    def test_invocation_in_attribute(self):
+        tmpl = Template("""<doc xmlns:py="http://markup.edgewall.org/">
+          <py:def function="echo(what)">${what or 'something'}</py:def>
+          <p class="${echo('foo')}">bar</p>
+        </doc>""")
+        self.assertEqual("""<doc>
+          <p class="foo">bar</p>
+        </doc>""", str(tmpl.generate()))
+
+    def test_invocation_in_attribute_none(self):
+        tmpl = Template("""<doc xmlns:py="http://markup.edgewall.org/">
+          <py:def function="echo()">${None}</py:def>
+          <p class="${echo()}">bar</p>
+        </doc>""")
+        self.assertEqual("""<doc>
+          <p>bar</p>
+        </doc>""", str(tmpl.generate()))
+
 
 class ForDirectiveTestCase(unittest.TestCase):
     """Tests for the `py:for` template directive."""