<cobbe at ccs dot neu dot edu>
This software is distributed under a BSD-style license (see license.txt).
This package provides two files, _check-values.ss_ and
_check-values-tests.ss_. The former defines two macros, which make it
easier to write SchemeUnit test cases for functions and other forms that
return multiple values.
The second file defines a SchemeUnit test suite for the macros in
check-values.ss. Note that most of these test cases are *SUPPOSED* to
fail; I'm interested primarily in ensuring that the message is formatted
correctly in case of failure. These test cases may also be useful examples
of how to use the two macros.
> (check-values actual ((same? expected) ...) [msg])
This macro checks an expression that produces multiple values. The first
argument, actual, is the expression to be tested. Unlike the other checks
in SchemeUnit, this is a macro, and you should *NOT* wrap actual in a
thunk! The sequence of (same? expected) lists specify the values that
actual should produce, along with the predicate to be used to compare the
(check-values actual ((same_1 expected_1) ... (same_n expected_n)))
succeeds if actual produces values v_1 through v_n and if
(check same_i v_i expected_i)
succeeds for all i between 1 and n.
As with other SchemeUnit checks, this form accepts an optional message
If the check fails, it fails with a message that contains the original
message, if any, and indicate the cause of the error: if actual produced
the wrong number of values, or which produced value failed to match the
corresponding expected value.
(check-values (quotient/remainder 5 2) ([= 2] [= 1]))
should succeed, and
(check-values (quotient/remainder 5 2) ([= 2]))
will fail with a message indicating that the test case expected 1 value but
> (check-values* same? actual (expected ...) [msg])
This macro is an optimization of check-values for the case in which all
values are to be compared with the same equality predicate.
(check-values* EQ EXPR (V1 ...))
expands (roughly) to
(check-values EXPR ((EQ V1) ...))
You'd write the two examples above with check-values as follows:
(check-values = (quotient/remainder 5 2) (2 1))
(check-values = (quotient/remainder 5 2) (2))
1) Right now, I have to run the test cases by hand and look at the
resulting messages to make sure they're formatted correctly. Is it
possible to write a meta-test-case that would automate this process?
2) The backtrace in the GUI isn't very helpful; it shows only the call to
test/graphical-ui. (This might be because of .zo compilation.)
* since version 1.0:
- documented test cases
- added keywords, CHANGES, TODO, usage examples to doc.txt
- fixed bug in calls to raise-syntax-error
Carl Eastlund suggested (and I think implemented the initial draft of) the
generalization from check-values* to check-values.