Saturday, June 19, 2021

Running Standalone TAP Tests

Recent discussion set me thinking about what would be involved in setting up standalone TAP tests for Postgres, to do, say, more code coverage than we get from the current core tests. So I started experimenting. And with a tiny bit of Makefile magic it turns out to be absurdly easy.

You need just two things: an entirely boilerplate Makefile and a tiny bit of glue at the top of your TAP test files.

First let's look at the Makefile. Here it is in its entirety:


PG_CONFIG = pg_config
PGXS := $(shell $(PG_CONFIG) --pgxs)
include $(PGXS)

# install_path for PostgreSQL binaries etc
PG_INSTALL_ROOT := $(dir $(shell $(PG_CONFIG) --bindir))

# where to find PostgresNode and friends
PG_NODE_LOC = $(top_srcdir)/src/test/perl
export PG_NODE_LOC

Then in your TAP test perl file(s) (which should reside in a subdirectory called "t") you put this:

use lib "$ENV{PG_NODE_LOC}";

use PostgresNode;
use Test::More;

local $ENV{PG_REGRESS} = "/bin/true";

my $node_inst = $ENV{PG_INSTALL_ROOT};

# for pre--release-14 releases you would possibly set LD_LIBRARY_PATH
# based on this. For release 14 and up PostgresNode does that for you
# via the install_path parameter.

my $node = PostgresNode->get_new_node('dummy', install_path => $node_inst);


That's all you need. Given that you can run your TAP tests with just a Postgres installation, as in this example:

andrew@emma:tests $ make PG_CONFIG=../inst.head.5701/bin/pg_config installcheck
rm -rf '/home/andrew/pgl/tests'/tmp_check
/usr/bin/mkdir -p '/home/andrew/pgl/tests'/tmp_check
cd ./ && TESTDIR='/home/andrew/pgl/tests' PATH="/home/andrew/pgl/inst.head.5701/bin:$PATH" PGPORT='65701' \
  top_builddir='/home/andrew/pgl/tests//home/andrew/pgl/inst.head.5701/lib/postgresql/pgxs/src/makefiles/../..' \
  PG_REGRESS='/home/andrew/pgl/tests//home/andrew/pgl/inst.head.5701/lib/postgresql/pgxs/src/makefiles/../../src/test/regress/pg_regress' \
  REGRESS_SHLIB='/src/test/regress/' \
  /usr/bin/prove -I /home/andrew/pgl/inst.head.5701/lib/postgresql/pgxs/src/makefiles/../../src/test/perl/ -I ./  t/*.pl
t/ .. ok   
All tests successful.
Files=1, Tests=1,  3 wallclock secs ( 0.04 usr  0.01 sys +  1.22 cusr  0.36 csys =  1.63 CPU)
Result: PASS

The Makefile and a demo TAP test are at This Gitlab repo

In the next episode, we'll look at how to leverage this so that your standalone tests are run by your buildfarm animal.

1 comment:

  1. Turns out it's even simpler than this. Watch the git repo. :-)