support for [define VARIABLE] where VARIABLE contains dotted attributes

[GoogleCodeExporter]

I have a use case for overriding attributes of objects provided through the 
template's fed data, i'd like to be considered for inclusion in EZT.

Next to being useful in my case, i read the documented syntax to leave room for 
it (the define takes a VARIABLE, and a variable is described to optionally 
contain dotted attributes).

Below is a patch that works for me. It still requires every component of a 
provided refname to be a valid reference.  If it isn't adequate, i'm glad to 
rework it upon your review.

thanks,
-seb.


$ svn diff
Index: ezt.py
===================================================================
--- ezt.py  (revision 38)
+++ ezt.py  (working copy)
@@ -486,11 +486,16 @@
     raise UnknownReference(refname, filename, line_number)

   # walk the rest of the dotted reference
+  partial_refname = start
   for attr in rest:
-    try:
-      ob = getattr(ob, attr)
-    except AttributeError:
-      raise UnknownReference(refname, filename, line_number)
+    partial_refname = '%s.%s' % (partial_refname, attr)
+    if ctx.defines.has_key(partial_refname):
+      ob = ctx.defines[partial_refname]
+    else:
+      try:
+        ob = getattr(ob, attr)
+      except AttributeError:
+        raise UnknownReference(refname, filename, line_number)

   # make sure we return a string instead of some various Python types
   if isinstance(ob, (IntType, FloatType, LongType)):
Index: tests/ezt_test.py
===================================================================
--- tests/ezt_test.py   (revision 38)
+++ tests/ezt_test.py   (working copy)
@@ -178,6 +178,16 @@
     d = self._runTemplate('[define RED]blue[end]RED = [RED]', {})
     self.assertEquals('RED = blue', d)

+  def testDefineAttributes(self):
+    class _BlahBlah:
+      def __init__(self, foo, bar):
+        self.foo = foo
+        self.bar = bar
+    o = _BlahBlah('freedom', 'good')
+    d = self._runTemplate('[define X.bar]slavery[end][X.foo] = [X.bar]',
+                          {'X': o})
+    self.assertEquals('freedom = slavery', d)
+
   def testDefineUnicode(self):
     d = self._runTemplate(u'[define HEART]���[end]HEART = [HEART]', {})
     self.assertEquals(u'HEART = ���', d)

Original issue reported on code.google.com by s...@google.com on 27 May 2015 at 8:40

[gstein]

CC: @cmpilato