automated test of json2csv function

initial version for review

nltk/test/unit/test_json2csv_corpus.py

+'''
+Created on 6 de may. de 2015
+
+@author: lorenzorubio
+'''
+import unittest
+import os
+import filecmp
+from nltk.twitter.util import guess_path, json2csv, json2csv_entities
+
+class Test(unittest.TestCase):
+
+
+    def setUp(self):
+        from nltk.corpus import tweets
+        self.inpf = tweets.abspath("tweets.20150430-223406.json")
+        pass
+
+
+    def tearDown(self):
+        pass
+
+
+    def testTextOutput(self):
+        outf = os.path.join(guess_path("twitter-files"), 'tweets.20150430-223406.text.csv')
+        json2csv(self.inpf, outf,
+                 ['text'])
+
+        assert filecmp.cmp(outf,
+                       'tweets.20150430-223406.text.csv.ref'), 'Error in csv file'
+
+
+if __name__ == "__main__":
+    unittest.main()
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