A method is provided to prioritize testing of computer program code comprising: determining first test coverages of items within a first source code version for multiple tests; storing in a non-transitory storage device, a first history that indicates the determined first test coverages of the items within the first source code version; identifying occurrences of the items within a second source code version; determining first weights associated with tests, wherein a respective weight associated with a respective test is indicative of a respective number of respective items within the second source code version that are covered by the respective associated test according to the first history; and prioritizing the multiple respective tests based at least in part upon the determined first weights.