tester.fs (lib) ☞

The tester.fs library helps you write test assertions.

Usage

Write test cases between the words T{ and T}, and use -> to delimit the program from the expected stack values.

An example test suite might look like this:

require tester.fs

: main
  T{ 1 2 3 rot     -> 2 3 1   }T
  T{ 4 dup *       -> 16      }T
  T{ 5 6 tuck over -> 6 5 6 5 }T ;

Word Index

T{ ( – )

Marks the start of a test case. Mostly syntactic sugar, but also tracks the current stack depth to preserve values not part of the test.

-> ( … – )

Delimits the code to be tested from the expected stack. Essentially stores the full stack (up to 32 values) so it can be compared against the expected values later.

}T ( … – )

Marks the end of the expected test values (and the test case). This will compare the current stack to the stored stack values (and reset the stack).

error ( c-addr u – )

A deferred word that receives an error message if a test case failed. By default, this will immediately stop the execution of the program. You can override this behaviour by pointing error-xt to your own routine:

\ using an anonymous word
:noname type cr ; error-xt !

\ using an existing word
' report-error error-xt !