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

tglsfdc · tglsfdc · commit fc8b81a291bf · 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
@@ -6300,6 +6300,8 @@ exec_cast_value(PLpgSQL_execstate *estate,
 			ExprContext *econtext = estate->eval_econtext;
 			MemoryContext oldcontext;
 
+			SPI_push();
+
 			oldcontext = MemoryContextSwitchTo(get_eval_mcontext(estate));
 
 			econtext->caseValue_datum = value;
@@ -6313,6 +6315,8 @@ 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
@@ -5643,3 +5643,22 @@ 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;
+$$;
+ERROR:  value for domain plpgsql_domain violates check constraint "plpgsql_domain_check"
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at assignment
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
@@ -4428,3 +4428,25 @@ exception when others then
   null; -- do nothing
 end;
 $$;
+
+-- 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
`@@ -6300,6 +6300,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6300`	`6300`	`ExprContext *econtext = estate->eval_econtext;`
`6301`	`6301`	`MemoryContext oldcontext;`
`6302`	`6302`
	`6303`	`+ SPI_push();`
	`6304`	`+`
`6303`	`6305`	`oldcontext = MemoryContextSwitchTo(get_eval_mcontext(estate));`
`6304`	`6306`
`6305`	`6307`	`econtext->caseValue_datum = value;`
`@@ -6313,6 +6315,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6313`	`6315`	`cast_entry->cast_in_use = false;`
`6314`	`6316`
`6315`	`6317`	`MemoryContextSwitchTo(oldcontext);`
	`6318`	`+`
	`6319`	`+ SPI_pop();`
`6316`	`6320`	`}`
`6317`	`6321`	`}`
`6318`	`6322`