D Language Unittesting Unittest blocks
Example
Tests are an excellent way to ensure stable, bug-free applications. They serve as an interactive documentation and allow to modify code without fear to break functionality. D provides a convenient and native syntax for unittest block as part of the D language. Anywhere in a D module unittest blocks can be used to test functionality of the source code.
/**
Yields the sign of a number.
Params:
n = number which should be used to check the sign
Returns:
1 for positive n, -1 for negative and 0 for 0.
*/
T sgn(T)(T n)
{
if (n == 0)
return 0;
return (n > 0) ? 1 : -1;
}
// this block will only be executed with -unittest
// it will be removed from the executable otherwise
unittest
{
// go ahead and make assumptions about your function
assert(sgn(10) == 1);
assert(sgn(1) == 1);
assert(sgn(-1) == -1);
assert(sgn(-10) == -1);
}
