add function duplicatedColumnNames to address issue: hide traceback f…

…rom users codeforsanjose#3; correct unit tests

validate.py

@@ -43,14 +43,20 @@ def validate_columns(input_file):
                 raise NoDataError("Data file contains fewer than 2 rows!")
 
 
+def validate_columns_simple_output(input_file):
+    try:
+        validate_columns(input_file)
+    except Exception as e:
+        print e
 
 
 if __name__ == '__main__':
     if len(sys.argv) is 1:
         print "no arguments privided; running the program against some sample CSV files"
-        validate_columns("test_files/valid.csv")
-        validate_columns("test_files/rowLengthMismatch.csv")
-        validate_columns("test_files/tooFewColumns.csv")
+        validate_columns_simple_output("test_files/valid.csv")
+        validate_columns_simple_output("test_files/rowLengthMismatch.csv")
+        validate_columns_simple_output("test_files/duplicatedColumnNames.csv")
+        validate_columns_simple_output("test_files/tooFewColumns.csv")
     else:
         for arg in sys.argv[1:]:
             if os.path.isfile(arg):

validator tests.py

@@ -1,7 +1,8 @@
 import unittest
 import sys
 
-from validate import validate_columns
+from validate import validate_columns, validate_columns_simple_output, \
+    DuplicateColumnError, NoDataError, ColumnMismatchError
 
 class TestCSVValidator(unittest.TestCase):
 
@@ -10,15 +11,15 @@ def test_empty_arg(self):
             validate_columns('')
 
     def test_row_lengths(self):
-        with self.assertRaises(ValueError):
+        with self.assertRaises(NoDataError):
             validate_columns('test_files/tooFewColumns.csv')
 
     def test_duplicated_column_names(self):
-        with self.assertRaises(ValueError):
+        with self.assertRaises(DuplicateColumnError):
             validate_columns('test_files/duplicatedColumnNames.csv')
 
     def test_row_length_mismatch(self):
-        with self.assertRaises(ValueError):
+        with self.assertRaises(ColumnMismatchError):
             validate_columns('test_files/rowLengthMismatch.csv')
 
 if __name__ == '__main__':