Abstract: Various technologies and techniques are disclosed for using historical trends from prior tests to prioritize how failures are reported in later tests. After a user changes a software development project, one or more tests are run to detect failures during execution of the tests. Any detected failures are analyzed in comparison with historical failures for the software development project across tests run for multiple users. Any detected failures are categorized as new or old. New failures are reported with a different emphasis than old failures, such as with new failures being reported as a higher priority than old failures.

Abstract: A system and method for testing modified code paths without testing unmodified code paths is described. During testing of the baseline build of a program, code coverage data is generated. The code coverage data identifies which test implicates which code path of the baseline build. When a modification of the baseline build is made, the modified build may be differentiated to determine what code of the modified build was changed. When the modified build is differentiated, the code coverage data for the modified code path is mapped to appropriate tests. The tests may then be used to test the changed code path without requiring testing of all the code paths of the modified build.