Cause plpgsql to throw an error if "INTO rowtype_var" is followed by a comma.

tglsfdc · tglsfdc · commit e664969f0f3b · 2010-03-02T16:14:39.000Z
Per bug #5352, this helps to provide a useful error message if the user
tries to do something presently unsupported, namely use a rowtype variable
as a member of a multiple-item INTO list.
diff --git a/src/pl/plpgsql/src/gram.y b/src/pl/plpgsql/src/gram.y
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.140 2010/01/19 01:35:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.141 2010/03/02 16:14:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2881,18 +2881,39 @@ read_into_target(PLpgSQL_rec **rec, PLpgSQL_row **row, bool *strict)
 		tok = yylex();
 	}
 
+	/*
+	 * Currently, a row or record variable can be the single INTO target,
+	 * but not a member of a multi-target list.  So we throw error if there
+	 * is a comma after it, because that probably means the user tried to
+	 * write a multi-target list.  If this ever gets generalized, we should
+	 * probably refactor read_into_scalar_list so it handles all cases.
+	 */
 	switch (tok)
 	{
 		case T_DATUM:
 			if (yylval.wdatum.datum->dtype == PLPGSQL_DTYPE_ROW)
 			{
 				check_assignable(yylval.wdatum.datum, yylloc);
 				*row = (PLpgSQL_row *) yylval.wdatum.datum;
+
+				if ((tok = yylex()) == ',')
+					ereport(ERROR,
+							(errcode(ERRCODE_SYNTAX_ERROR),
+							 errmsg("record or row variable cannot be part of multiple-item INTO list"),
+							 parser_errposition(yylloc)));
+				plpgsql_push_back_token(tok);
 			}
 			else if (yylval.wdatum.datum->dtype == PLPGSQL_DTYPE_REC)
 			{
 				check_assignable(yylval.wdatum.datum, yylloc);
 				*rec = (PLpgSQL_rec *) yylval.wdatum.datum;
+
+				if ((tok = yylex()) == ',')
+					ereport(ERROR,
+							(errcode(ERRCODE_SYNTAX_ERROR),
+							 errmsg("record or row variable cannot be part of multiple-item INTO list"),
+							 parser_errposition(yylloc)));
+				plpgsql_push_back_token(tok);
 			}
 			else
 			{

Original file line number	Diff line number	Diff line change
`@@ -8,7 +8,7 @@`
`8`	`8`	`*`
`9`	`9`	`*`
`10`	`10`	`* IDENTIFICATION`
`11`		`- * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.140 2010/01/19 01:35:30 tgl Exp $`
	`11`	`+ * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.141 2010/03/02 16:14:39 tgl Exp $`
`12`	`12`	`*`
`13`	`13`	`*-------------------------------------------------------------------------`
`14`	`14`	`*/`
`@@ -2881,18 +2881,39 @@ read_into_target(PLpgSQL_rec rec, PLpgSQL_row row, bool *strict)`
`2881`	`2881`	`tok = yylex();`
`2882`	`2882`	`}`
`2883`	`2883`
	`2884`	`+ /*`
	`2885`	`+ * Currently, a row or record variable can be the single INTO target,`
	`2886`	`+ * but not a member of a multi-target list. So we throw error if there`
	`2887`	`+ * is a comma after it, because that probably means the user tried to`
	`2888`	`+ * write a multi-target list. If this ever gets generalized, we should`
	`2889`	`+ * probably refactor read_into_scalar_list so it handles all cases.`
	`2890`	`+ */`
`2884`	`2891`	`switch (tok)`
`2885`	`2892`	`{`
`2886`	`2893`	`case T_DATUM:`
`2887`	`2894`	`if (yylval.wdatum.datum->dtype == PLPGSQL_DTYPE_ROW)`
`2888`	`2895`	`{`
`2889`	`2896`	`check_assignable(yylval.wdatum.datum, yylloc);`
`2890`	`2897`	`row = (PLpgSQL_row ) yylval.wdatum.datum;`
	`2898`	`+`
	`2899`	`+ if ((tok = yylex()) == ',')`
	`2900`	`+ ereport(ERROR,`
	`2901`	`+ (errcode(ERRCODE_SYNTAX_ERROR),`
	`2902`	`+ errmsg("record or row variable cannot be part of multiple-item INTO list"),`
	`2903`	`+ parser_errposition(yylloc)));`
	`2904`	`+ plpgsql_push_back_token(tok);`
`2891`	`2905`	`}`
`2892`	`2906`	`else if (yylval.wdatum.datum->dtype == PLPGSQL_DTYPE_REC)`
`2893`	`2907`	`{`
`2894`	`2908`	`check_assignable(yylval.wdatum.datum, yylloc);`
`2895`	`2909`	`rec = (PLpgSQL_rec ) yylval.wdatum.datum;`
	`2910`	`+`
	`2911`	`+ if ((tok = yylex()) == ',')`
	`2912`	`+ ereport(ERROR,`
	`2913`	`+ (errcode(ERRCODE_SYNTAX_ERROR),`
	`2914`	`+ errmsg("record or row variable cannot be part of multiple-item INTO list"),`
	`2915`	`+ parser_errposition(yylloc)));`
	`2916`	`+ plpgsql_push_back_token(tok);`
`2896`	`2917`	`}`
`2897`	`2918`	`else`
`2898`	`2919`	`{`