Correctly handle scanner that are smaller than expected

Fixes #72.

Author: wbolster

NEWS.rst

@@ -9,6 +9,10 @@ HappyBase 0.9
 
 Release date: *not yet released*
 
+* Fix an issue where scanners would return fewer results than expected due to
+  HBase not always behaving as its documentation suggests. (`issue #72
+  <https://github.com/wbolster/happybase/issues/72>`_).
+
 * Add support for the Thrift compact protocol (``TCompactProtocol``) in
   :py:class:`Connection`.
 

happybase/table.py

@@ -389,6 +389,9 @@ def scan(self, row_start=None, row_stop=None, row_prefix=None,
                     items = self.connection.client.scannerGetList(
                         scan_id, how_many)
 
+                if not items:
+                    break  # scan has finished
+
                 n_fetched += len(items)
 
                 for n_returned, item in enumerate(items, n_returned + 1):
@@ -401,11 +404,7 @@ def scan(self, row_start=None, row_stop=None, row_prefix=None,
                     yield item.row, row
 
                     if limit is not None and n_returned == limit:
-                        return
-
-                # Avoid round-trip when exhausted
-                if len(items) < how_many:
-                    break
+                        break  # not interested in the remainder
         finally:
             self.connection.client.scannerClose(scan_id)
             logger.debug(