spring-projects/spring-data-mongodb — pull request #116 by thomasdarimont (2014-01-30 14:01:01+00:00)
Title: DATAMONGO-838 - Cannot refer to expression based field in group operation.

DATAMONGO-838 - Cannot refer to expression based field in group operation.

Previously we didn't set a proper target value for a generated expression field in a Aggregation Framework expression. As a potential fix we just use the alias as the target field.

Please revise.