Revert changes to zip error messages

Author: dhimmel

pandas/io/common.py

@@ -336,12 +336,16 @@ def _get_handle(path_or_buf, mode, encoding=None, compression=None,
         elif compression == 'zip':
             import zipfile
             zip_file = zipfile.ZipFile(path_or_buf)
-            try:
-                name, = zip_file.namelist()
-            except ValueError:
-                raise ValueError('Zip file must contain exactly one file {}'
+            zip_names = zip_file.namelist()
+            if len(zip_names) == 1:
+                f = zip_file.open(zip_names.pop())
+            elif len(zip_names) == 0:
+                raise ValueError('Zero files found in ZIP file {}'
                                  .format(path_or_buf))
-            f = zip_file.open(name)
+            else:
+                raise ValueError('Multiple files found in ZIP file.'
+                                 ' Only one file per ZIP: {}'
+                                 .format(zip_names))
 
         # XZ Compression
         elif compression == 'xz':

pandas/io/tests/parser/compression.py

@@ -45,17 +45,17 @@ def test_zip(self):
                 tmp.writestr(file_name, data)
             tmp.close()
 
-            self.assertRaisesRegexp(ValueError, 'must contain exactly one file',
+            self.assertRaisesRegexp(ValueError, 'Multiple files',
                                     self.read_csv, path, compression='zip')
 
-            self.assertRaisesRegexp(ValueError, 'must contain exactly one file',
+            self.assertRaisesRegexp(ValueError, 'Multiple files',
                                     self.read_csv, path, compression='infer')
 
         with tm.ensure_clean() as path:
             tmp = zipfile.ZipFile(path, mode='w')
             tmp.close()
 
-            self.assertRaisesRegexp(ValueError, 'must contain exactly one file',
+            self.assertRaisesRegexp(ValueError, 'Zero files',
                                     self.read_csv, path, compression='zip')
 
         with tm.ensure_clean() as path: