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a8591a55f0
* test-suite/tests/numbers.test (test-eqv?): Remove special handling of
zeroes. Zeroes are now compared like all other numbers. Exact
numbers are compared with `eqv?' and inexact numbers are compared to
within test-epsilon.
Rework the testing framework for number-theoretic division operators:
`euclidean/', `euclidean-quotient', `euclidean-remainder',
`centered/', `centered-quotient', and `centered-remainder'.
Previously we compared all test results against a simple scheme
implementation of the same operations. However, these operations have
discontinuous jumps where a tiny change in the inputs can lead to a
large change in the outputs, e.g.:
(euclidean/ 130.00000000000 10/7) ==> 91.0 and 0.0
(euclidean/ 129.99999999999 10/7) ==> 90.0 and 1.42857142856141
In the new testing scheme, we compare values against the simple
implementations only if the input arguments contain an infinity or a
NaN. In the common case of two finite arguments, we simply make sure
that the outputs of all three operators (e.g. `euclidean/',
`euclidean-quotient', `euclidean-remainder') equal each other, that
outputs are exact iff both inputs are exact, and that the required
properties of the operator are met: that Q is an integer, that R is
within the specified range, and that N = Q*D + R.
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| lalr | ||
| standalone | ||
| tests | ||
| vm | ||
| ChangeLog-2008 | ||
| guile-test | ||
| lib.scm | ||
| Makefile.am | ||
| README | ||
This directory contains some tests for Guile, and some generic test support code. To run these tests, you will need a version of Guile more recent than 15 Feb 1999 --- the tests use the (ice-9 and-let*) and (ice-9 getopt-long) modules, which were added to Guile around then. For information about how to run the test suite, read the usage instructions in the comments at the top of the guile-test script. You can reference the file `lib.scm' from your own code as the module (test-suite lib); it also has comments at the top and before each function explaining what's going on. Please write more Guile tests, and send them to bug-guile@gnu.org. We'll merge them into the distribution. All test suites must be licensed for our use under the GPL, but I don't think I'm going to collect assignment papers for them. Some test suite philosophy: GDB has an extensive test suite --- around 6300 tests. Every time the test suite catches a bug, it's great. GDB is so complicated that folks are often unable to get a solid understanding of the code before making a change --- we just don't have time. You'll see people say things like, "Here's a fix for X; it doesn't cause any regressions." The subtext is, I made a change that looks reasonable, and the test suite didn't complain, so it must be okay. I think this is terrible, because it suggests that the writer is using the test suite as a substitute for having a rock-solid explanation of why their changes are correct. The problem is that any test suite is woefully incomplete. Diligent reasoning about code can catch corner conditions or limitations that no test suite will ever find. Jim's rule for test suites: Every test suite failure should be a complete, mysterious surprise, never a possibility you were prepared for. Any other attitude indicates that you're using the test suite as a crutch, which you need only because your understanding is weak.