Rearrange core regression tests to reduce cross-script dependencies.

The idea behind this patch is to make it possible to run individual
test scripts without running the entire core test suite.  Making all
the scripts completely independent would involve a massive rewrite,
and would probably be worse for coverage of things like concurrent DDL.
So this patch just does what seems practical with limited changes.

The net effect is that any test script can be run after running
limited earlier dependencies:
* all scripts depend on test_setup
* many scripts depend on create_index
* other dependencies are few in number, and are documented in
  the parallel_schedule file.

To accomplish this, I chose a small number of commonly-used tables
and moved their creation and filling into test_setup.  Later scripts
are expected not to modify these tables' data contents, for fear of
affecting other scripts' results.  Also, our former habit of declaring
all C functions in one place is now gone in favor of declaring them
where they're used, if that's just one script, or in test_setup if
necessary.

There's more that could be done to remove some of the remaining
inter-script dependencies, but significantly more-invasive changes
would be needed, and at least for now it doesn't seem worth it.

Discussion: https://postgr.es/m/1114748.1640383217@sss.pgh.pa.us

1 files changed, 33 insertions, 0 deletions

diff --git a/src/test/regress/sql/triggers.sql b/src/test/regress/sql/triggers.sql
index 2657d127d5..4cc096265d 100644
--- a/src/test/regress/sql/triggers.sql
+++ b/src/test/regress/sql/triggers.sql
@@ -2,6 +2,39 @@
 -- TRIGGERS
 --
 
+-- directory paths and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set autoinclib :libdir '/autoinc' :dlsuffix
+\set refintlib :libdir '/refint' :dlsuffix
+\set regresslib :libdir '/regress' :dlsuffix
+
+CREATE FUNCTION autoinc ()
+	RETURNS trigger
+	AS :'autoinclib'
+	LANGUAGE C;
+
+CREATE FUNCTION check_primary_key ()
+	RETURNS trigger
+	AS :'refintlib'
+	LANGUAGE C;
+
+CREATE FUNCTION check_foreign_key ()
+	RETURNS trigger
+	AS :'refintlib'
+	LANGUAGE C;
+
+CREATE FUNCTION trigger_return_old ()
+        RETURNS trigger
+        AS :'regresslib'
+        LANGUAGE C;
+
+CREATE FUNCTION set_ttdummy (int4)
+        RETURNS int4
+        AS :'regresslib'
+        LANGUAGE C STRICT;
+
 create table pkeys (pkey1 int4 not null, pkey2 text not null);
 create table fkeys (fkey1 int4, fkey2 text, fkey3 int);
 create table fkeys2 (fkey21 int4, fkey22 text, pkey23 int not null);