added test code for rbase and changed rbase to return None rather than error out on R-type objects that lack an extracted attribute

Author: davidthaler

rforecast/rbase.py

@@ -10,7 +10,7 @@ def colnames(x):
   try:
     out = robjects.r('colnames')(x)
     if out is robjects.NULL:
-      raise TypeError('Object does not have colnames attribute.')
+      return None
     else:
       return list(out)
   except NotImplementedError:
@@ -20,7 +20,7 @@ def dim(x):
   try:
     out = robjects.r('dim')(x)
     if out is robjects.NULL:
-      raise TypeError('Object does not have dim attribute.')
+      return None
     else:
       return list(out)
   except NotImplementedError:

test/test_rbase.py

@@ -0,0 +1,27 @@
+import unittest
+from rpy2 import robjects
+from rforecast import rbase, ts_io, converters, wrappers
+
+class rbaseTestCase(unittest.TestCase):
+
+  def setUp(self):
+    self.oil = ts_io.read_series('data/oil.csv')
+    self.oil_ts = converters.series_as_ts(self.oil)
+    self.mat = converters.matrix([[1,2,3],[2,3,4]])
+    self.acc = wrappers.accuracy(wrappers.thetaf(self.oil_ts))
+    
+  def testCls(self):
+    self.assertTrue('ts' in rbase.cls(self.oil_ts))
+    self.assertRaises(TypeError, rbase.cls, self.oil)
+    
+  def testDim(self):
+    self.assertListEqual(rbase.dim(self.mat), [2, 3])
+    self.assertTrue(rbase.dim(self.oil_ts) is None)    
+    self.assertRaises(TypeError, rbase.dim, self.oil)
+    
+  def testColnames(self):
+    self.assertRaises(TypeError, rbase.colnames, self.oil)
+    self.assertTrue(rbase.colnames(self.mat) is None)
+    self.assertTrue('MASE' in rbase.colnames(self.acc))
+
+