1. A method for testing functionality of a computer program based on at least one change to program code of the computer program comprising: a computer identifying one or more program functions within program code of a computer program affected by a program code change; the computer identifying program function calls made by the one or more program functions to other program functions; the computer adding the one or more program functions and program function calls to a program code database; the computer generating a mapping of relationships between the program functions of the program code; the computer querying a repository based on each of the program functions that are represented in the mapping of relationships, in order to retrieve one or more test scripts, wherein each test script can test the functionality of all the program functions that are represented in the mapping of relationships; and the computer consolidating the one or more test scripts into a test suite that comprehensively tests functionality of the computer program.