Fix missing outfuncs.c support for IncrementalSortPath.

For debugging purposes, Path nodes are supposed to have outfuncs
support, but this was overlooked in the original incremental sort patch.

While at it, clean up a couple other minor oversights, as well as
bizarre choice of return type for create_incremental_sort_path().
(All the existing callers just cast it to "Path *" immediately, so
they don't care, but some future caller might care.)

outfuncs.c fix by Zhijie Hou, the rest by me

Discussion: https://postgr.es/m/324c4d81d8134117972a5b1f6cdf9560@G08CNEXMBPEKD05.g08.fujitsu.local

1 files changed, 21 insertions, 2 deletions

diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index e2f177515da..07c93b4737a 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -1955,13 +1955,29 @@ _outProjectSetPath(StringInfo str, const ProjectSetPath *node)
 }
 
 static void
+_outSortPathInfo(StringInfo str, const SortPath *node)
+{
+	_outPathInfo(str, (const Path *) node);
+
+	WRITE_NODE_FIELD(subpath);
+}
+
+static void
 _outSortPath(StringInfo str, const SortPath *node)
 {
 	WRITE_NODE_TYPE("SORTPATH");
 
-	_outPathInfo(str, (const Path *) node);
+	_outSortPathInfo(str, node);
+}
 
-	WRITE_NODE_FIELD(subpath);
+static void
+_outIncrementalSortPath(StringInfo str, const IncrementalSortPath *node)
+{
+	WRITE_NODE_TYPE("INCREMENTALSORTPATH");
+
+	_outSortPathInfo(str, (const SortPath *) node);
+
+	WRITE_INT_FIELD(nPresortedCols);
 }
 
 static void
@@ -4058,6 +4074,9 @@ outNode(StringInfo str, const void *obj)
 			case T_SortPath:
 				_outSortPath(str, obj);
 				break;
+			case T_IncrementalSortPath:
+				_outIncrementalSortPath(str, obj);
+				break;
 			case T_GroupPath:
 				_outGroupPath(str, obj);
 				break;