Test matrices were previously simplified for the mock/* tests (e.g. d4410611, d489eb87) but not for real/all since the rules for which tests would run with which options was extremely complex. This only got more complex when new compression formats were added.
Because the loop-generated matrix was so large, mosts tests were skipped for most option combinations following arcane logic which was nearly impossible to decipher even when reading the code, and completely impossible from the test.pl interface. As a consequence, important tests got excluded. For example, backup from standby was excluded for most versions of PostgreSQL because it was only run once per distro, against the latest version to be included in that distro.
Simplify the tests by having a single run per PostgreSQL version and vary test parameters according to the capabilities of each version and the underlying distro. So, ZST testing is based on whether the distro supports ZST. Every test is run for each set of parameters based on the capabilities of the PostgreSQL version, e.g. backup from standby is not attempted on versions that don't support it.
Note that since more tests are running the overall time to run the mock/all tests has increased by about 20-25%. Some time may be saved my removing tests that are adequately covered by unit tests but that should the subject of another commit. Another option would be to limit some non version-specific tests to a single, well defined version of PostgreSQL, .e.g the version that is run by expect tests, currently 9.6.
The motivation for this refactor is that new storage drivers are coming and the loop-generated test matrix simply was not up to the task of adding them.
The following is an example of the new test log (note longer runtime of each test):
module=real, test=all, run=1, pg-version=10 (106.91s)
module=real, test=all, run=1, pg-version=9.5 (151.09s)
module=real, test=all, run=1, pg-version=9.2 (123.11s)
module=real, test=all, run=1, pg-version=9.1 (129s)
vs. the old test log (sub-second tests were skipped entirely):
module=real, test=all, run=2, pg-version=10 (0.31s)
module=real, test=all, run=3, pg-version=10 (0.26s)
module=real, test=all, run=4, pg-version=10 (60.39s)
module=real, test=all, run=1, pg-version=10 (69.12s)
module=real, test=all, run=6, pg-version=10 (34s)
module=real, test=all, run=5, pg-version=10 (42.75s)
module=real, test=all, run=2, pg-version=9.5 (0.21s)
module=real, test=all, run=3, pg-version=9.5 (0.21s)
module=real, test=all, run=4, pg-version=9.5 (0.21s)
module=real, test=all, run=5, pg-version=9.5 (0.26s)
module=real, test=all, run=6, pg-version=9.5 (0.21s)
module=real, test=all, run=1, pg-version=9.2 (72.78s)
module=real, test=all, run=2, pg-version=9.2 (0.26s)
module=real, test=all, run=3, pg-version=9.2 (0.31s)
module=real, test=all, run=4, pg-version=9.2 (0.21s)
module=real, test=all, run=5, pg-version=9.2 (0.21s)
module=real, test=all, run=6, pg-version=9.2 (0.21s)
module=real, test=all, run=1, pg-version=9.5 (88.41s)
module=real, test=all, run=2, pg-version=9.1 (0.21s)
module=real, test=all, run=3, pg-version=9.1 (0.26s)
module=real, test=all, run=4, pg-version=9.1 (0.21s)
module=real, test=all, run=5, pg-version=9.1 (0.31s)
module=real, test=all, run=6, pg-version=9.1 (0.26s)
module=real, test=all, run=1, pg-version=9.1 (72.4s)