Updating test cases when the output changes
If the output of a test has changed, but the new output is still correct, you can automatically update the sample output to match the new output like so:
$ make accept TEST=<test-name>
where <test-name> is the name of the test.
If you want to update a whole directory of tests to accept the new output, simply call make accept in that directory:
$ cd array/should_run $ make accept
make accept does not change the expected output of tests that are marked as expect_broken or expect_broken_for.
Some of the performance tests in perf/ check for peak memory usage. Peak memory usage is obtained when there is a major GC, so the peak value can be vulnerable to the timing of major GC. If peak_megabytes appears to increase, try running with RTS -h -i0.01 before and after. That makes major GC happen more often, and gives a much more accurate result.