Need to do SPI_push/SPI_pop around expression evaluation in plpgsql.

tglsfdc · tglsfdc · commit 674877e93a1b · 2016-11-06T12:09:36.000-05:00
We must do this in case the expression evaluation results in calling another plpgsql function (or, really, anything using SPI). I missed the need for this when I converted exec_cast_value() from doing a simple InputFunctionCall() to doing ExecEvalExpr() in commit 1345cc6. There is a SPI_push_conditional in InputFunctionCall(), so that there was no bug before that. Per bug #14414 from Marcos Castedo. Add a regression test based on his example, which was that a plpgsql function in a domain check constraint didn't work when assigning to a domain-type variable within plpgsql. Report: <20161106010947.1387.66380@wrigleys.postgresql.org>
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
@@ -6015,6 +6015,8 @@ exec_cast_value(PLpgSQL_execstate *estate,
 			ExprContext *econtext = estate->eval_econtext;
 			MemoryContext oldcontext;
 
+			SPI_push();
+
 			oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
 
 			econtext->caseValue_datum = value;
@@ -6028,6 +6030,8 @@ exec_cast_value(PLpgSQL_execstate *estate,
 			cast_entry->cast_in_use = false;
 
 			MemoryContextSwitchTo(oldcontext);
+
+			SPI_pop();
 		}
 	}
 
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
@@ -5611,3 +5611,22 @@ end;
 $$;
 ERROR:  unhandled assertion
 CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+-- Test use of plpgsql in a domain check constraint (cf. bug #14414)
+create function plpgsql_domain_check(val int) returns boolean as $$
+begin return val > 0; end
+$$ language plpgsql immutable;
+create domain plpgsql_domain as integer check(plpgsql_domain_check(value));
+do $$
+declare v_test plpgsql_domain;
+begin
+  v_test := 1;
+end;
+$$;
+do $$
+declare v_test plpgsql_domain := 1;
+begin
+  v_test := 0;  -- fail
+end;
+$$;
+ERROR:  value for domain plpgsql_domain violates check constraint "plpgsql_domain_check"
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at assignment
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
@@ -4390,3 +4390,25 @@ exception when others then
   null; -- do nothing
 end;
 $$;
+
+-- Test use of plpgsql in a domain check constraint (cf. bug #14414)
+
+create function plpgsql_domain_check(val int) returns boolean as $$
+begin return val > 0; end
+$$ language plpgsql immutable;
+
+create domain plpgsql_domain as integer check(plpgsql_domain_check(value));
+
+do $$
+declare v_test plpgsql_domain;
+begin
+  v_test := 1;
+end;
+$$;
+
+do $$
+declare v_test plpgsql_domain := 1;
+begin
+  v_test := 0;  -- fail
+end;
+$$;

Original file line number	Diff line number	Diff line change
`@@ -6015,6 +6015,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6015`	`6015`	`ExprContext *econtext = estate->eval_econtext;`
`6016`	`6016`	`MemoryContext oldcontext;`
`6017`	`6017`
	`6018`	`+ SPI_push();`
	`6019`	`+`
`6018`	`6020`	`oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);`
`6019`	`6021`
`6020`	`6022`	`econtext->caseValue_datum = value;`
`@@ -6028,6 +6030,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6028`	`6030`	`cast_entry->cast_in_use = false;`
`6029`	`6031`
`6030`	`6032`	`MemoryContextSwitchTo(oldcontext);`
	`6033`	`+`
	`6034`	`+ SPI_pop();`
`6031`	`6035`	`}`
`6032`	`6036`	`}`
`6033`	`6037`