资料来源 : Free On-Line Dictionary of Computing

Test coverage
     
         A measure of the proportion of a program exercised
        by a {test suite}, usually expressed as a percentage.  This
        will typically involve collecting information about which
        parts of a program are actually executed when running the test
        suite in order to identify which branches of {conditional
        statements} which have been taken.
     
        The most basic level of test coverage is {code coverage
        testing} and the most methodical is {path coverage testing}.
        Some intermediate levels of test coverage exist, but are
        rarely used.
     
        The standard {Unix} tool for measuring test coverage is
        {tcov}, which annotates {C} or {Fortran} source with the
        results of a test coverage analysis.  {GCT} is a {GNU}
        equivalent.
     
        (2001-05-20)