Fix pg_get_indexdef()'s behavior for included index columns.

The multi-argument form of pg_get_indexdef() failed to print anything when
asked to print a single index column that is an included column rather than
a key column.  This seems an unintentional result of someone having tried
to take a short-cut and use the attrsOnly flag for two different purposes.
To fix, split said flag into two flags, attrsOnly which suppresses
non-attribute info, and keysOnly which suppresses included columns.
Add a test case using psql's \d command, which relies on that function.

(It's mighty tempting at this point to replace pg_get_indexdef_worker's
mess of boolean flag arguments with a single bitmask-of-flags argument,
which would allow making the call sites much more self-documenting.
But I refrained for the moment.)

Discussion: https://postgr.es/m/21724.1531943735@sss.pgh.pa.us

src/backend/utils/adt/ruleutils.c

@@ -320,7 +320,8 @@ static void decompile_column_index_array(Datum column_index_array, Oid relId,
 static char *pg_get_ruledef_worker(Oid ruleoid, int prettyFlags);
 static char *pg_get_indexdef_worker(Oid indexrelid, int colno,
 					   const Oid *excludeOps,
-					   bool attrsOnly, bool showTblSpc, bool inherits,
+					   bool attrsOnly, bool keysOnly,
+					   bool showTblSpc, bool inherits,
 					   int prettyFlags, bool missing_ok);
 static char *pg_get_statisticsobj_worker(Oid statextid, bool missing_ok);
 static char *pg_get_partkeydef_worker(Oid relid, int prettyFlags,
@@ -1097,7 +1098,9 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 
 	prettyFlags = PRETTYFLAG_INDENT;
 
-	res = pg_get_indexdef_worker(indexrelid, 0, NULL, false, false, false,
+	res = pg_get_indexdef_worker(indexrelid, 0, NULL,
+								 false, false,
+								 false, false,
 								 prettyFlags, true);
 
 	if (res == NULL)
@@ -1117,8 +1120,10 @@ pg_get_indexdef_ext(PG_FUNCTION_ARGS)
 
 	prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT;
 
-	res = pg_get_indexdef_worker(indexrelid, colno, NULL, colno != 0, false,
+	res = pg_get_indexdef_worker(indexrelid, colno, NULL,
-								 false, prettyFlags, true);
+								 colno != 0, false,
+								 false, false,
+								 prettyFlags, true);
 
 	if (res == NULL)
 		PG_RETURN_NULL();
@@ -1134,10 +1139,13 @@ pg_get_indexdef_ext(PG_FUNCTION_ARGS)
 char *
 pg_get_indexdef_string(Oid indexrelid)
 {
-	return pg_get_indexdef_worker(indexrelid, 0, NULL, false, true, true, 0, false);
+	return pg_get_indexdef_worker(indexrelid, 0, NULL,
+								  false, false,
+								  true, true,
+								  0, false);
 }
 
-/* Internal version that just reports the column definitions */
+/* Internal version that just reports the key-column definitions */
 char *
 pg_get_indexdef_columns(Oid indexrelid, bool pretty)
 {
@@ -1145,7 +1153,9 @@ pg_get_indexdef_columns(Oid indexrelid, bool pretty)
 
 	prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT;
 
-	return pg_get_indexdef_worker(indexrelid, 0, NULL, true, false, false,
+	return pg_get_indexdef_worker(indexrelid, 0, NULL,
+								  true, true,
+								  false, false,
 								  prettyFlags, false);
 }
 
@@ -1158,7 +1168,8 @@ pg_get_indexdef_columns(Oid indexrelid, bool pretty)
 static char *
 pg_get_indexdef_worker(Oid indexrelid, int colno,
 					   const Oid *excludeOps,
-					   bool attrsOnly, bool showTblSpc, bool inherits,
+					   bool attrsOnly, bool keysOnly,
+					   bool showTblSpc, bool inherits,
 					   int prettyFlags, bool missing_ok)
 {
 	/* might want a separate isConstraint parameter later */
@@ -1297,15 +1308,13 @@ pg_get_indexdef_worker(Oid indexrelid, int colno,
 		Oid			keycolcollation;
 
 		/*
-		 * attrsOnly flag is used for building unique-constraint and
+		 * Ignore non-key attributes if told to.
-		 * exclusion-constraint error messages. Included attrs are meaningless
-		 * there, so do not include them in the message.
 		 */
-		if (attrsOnly && keyno >= idxrec->indnkeyatts)
+		if (keysOnly && keyno >= idxrec->indnkeyatts)
 			break;
 
-		/* Report the INCLUDED attributes, if any. */
+		/* Otherwise, print INCLUDE to divide key and non-key attrs. */
-		if ((!attrsOnly) && keyno == idxrec->indnkeyatts)
+		if (!colno && keyno == idxrec->indnkeyatts)
 		{
 			appendStringInfoString(&buf, ") INCLUDE (");
 			sep = "";
@@ -1352,13 +1361,12 @@ pg_get_indexdef_worker(Oid indexrelid, int colno,
 			keycolcollation = exprCollation(indexkey);
 		}
 
-		if (!attrsOnly && (!colno || colno == keyno + 1))
+		/* Print additional decoration for (selected) key columns */
+		if (!attrsOnly && keyno < idxrec->indnkeyatts &&
+			(!colno || colno == keyno + 1))
 		{
 			Oid			indcoll;
 
-			if (keyno >= idxrec->indnkeyatts)
-				continue;
-
 			/* Add collation, if not default for column */
 			indcoll = indcollation->values[keyno];
 			if (OidIsValid(indcoll) && indcoll != keycolcollation)
@@ -2197,6 +2205,7 @@ pg_get_constraintdef_worker(Oid constraintId, bool fullCommand,
 															  false,
 															  false,
 															  false,
+															  false,
 															  prettyFlags,
 															  false));
 				break;

src/test/regress/expected/index_including.out

@@ -19,6 +19,16 @@ WHERE i.indrelid = 'tbl_include_reg'::regclass ORDER BY c.relname;
  CREATE INDEX tbl_include_reg_idx ON public.tbl_include_reg USING btree (c1, c2) INCLUDE (c3, c4)
 (2 rows)
 
+\d tbl_include_reg_idx
+Index "public.tbl_include_reg_idx"
+ Column |  Type   | Definition 
+--------+---------+------------
+ c1     | integer | c1
+ c2     | integer | c2
+ c3     | integer | c3
+ c4     | box     | c4
+btree, for table "public.tbl_include_reg"
+
 -- Unique index and unique constraint
 CREATE TABLE tbl_include_unique1 (c1 int, c2 int, c3 int, c4 box);
 INSERT INTO tbl_include_unique1 SELECT x, 2*x, 3*x, box('4,4,4,4') FROM generate_series(1,10) AS x;

src/test/regress/sql/index_including.sql

@@ -14,6 +14,7 @@ CREATE INDEX ON tbl_include_reg (c1, c2) INCLUDE (c1, c3);
 SELECT pg_get_indexdef(i.indexrelid)
 FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
 WHERE i.indrelid = 'tbl_include_reg'::regclass ORDER BY c.relname;
+\d tbl_include_reg_idx
 
 -- Unique index and unique constraint
 CREATE TABLE tbl_include_unique1 (c1 int, c2 int, c3 int, c4 box);