Index: trunk/psLib/test/types/Makefile.am
===================================================================
--- trunk/psLib/test/types/Makefile.am	(revision 13942)
+++ trunk/psLib/test/types/Makefile.am	(revision 14008)
@@ -19,4 +19,5 @@
 	tap_psMetadataItemParse \
 	tap_psMetadataUpdate \
+	tap_psMetadataOverlay \
 	tap_psMetadata_printing \
 	tap_psMetadata_copying \
Index: trunk/psLib/test/types/tap_psMetadataOverlay.c
===================================================================
--- trunk/psLib/test/types/tap_psMetadataOverlay.c	(revision 14008)
+++ trunk/psLib/test/types/tap_psMetadataOverlay.c	(revision 14008)
@@ -0,0 +1,288 @@
+/**
+*  C Implementation: tap_psMetadataOverlay
+*
+* Description: Tests for psMetadataOverlay
+*
+* Author: Eugene Magnier
+* Copyright: See COPYING file that comes with this distribution
+*
+*/
+#include <pslib.h>
+#include <string.h>
+#include "tap.h"
+#include "pstap.h"
+
+int main(void)
+{
+    psLogSetFormat("HLNM");
+    psLogSetLevel(PS_LOG_INFO);
+    plan_tests(14);
+    // psMetadataOverlay Tests
+
+    // overlay two metadatas : output should contain union of all entries
+    {
+        psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+        ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+    // overlay two metadatas, folder in output: output should contain union of all entries
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *sub = psMetadataAlloc();
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 1);
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 2);
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 3);
+
+	psMetadataAddMetadata (out, PS_LIST_TAIL, "SUB", 0, "", sub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (sub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+    // overlay two metadatas, folder in input: output should contain union of all entries
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *sub = psMetadataAlloc();
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 1);
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 2);
+	psMetadataAddS32 (sub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 3);
+
+	psMetadataAddMetadata (in, PS_LIST_TAIL, "SUB", 0, "", sub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (sub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+    // overlay two metadatas, folder in input & output, no-matched elements
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *inSub = psMetadataAlloc();
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB1", 0, "", 1);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB2", 0, "", 2);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB3", 0, "", 3);
+	psMetadataAddMetadata (in, PS_LIST_TAIL, "SUB", 0, "", inSub);
+
+	psMetadata *outSub = psMetadataAlloc();
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB1", 0, "", 1);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB2", 0, "", 2);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB3", 0, "", 3);
+	psMetadataAddMetadata (out, PS_LIST_TAIL, "SUB", 0, "", outSub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (inSub);
+	psFree (outSub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+    // overlay two metadatas, folder and subfolders in input & output, no-matched elements
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *inSub = psMetadataAlloc();
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB1", 0, "", 1);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB2", 0, "", 2);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.INSUB3", 0, "", 3);
+
+	psMetadata *inSubSub = psMetadataAlloc();
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.INSUB1", 0, "", 1);
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.INSUB2", 0, "", 2);
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.INSUB3", 0, "", 3);
+	psMetadataAddMetadata (inSub, PS_LIST_TAIL, "SUB", 0, "", inSubSub);
+
+	psMetadataAddMetadata (in, PS_LIST_TAIL, "SUB", 0, "", inSub);
+
+	psMetadata *outSub = psMetadataAlloc();
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB1", 0, "", 1);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB2", 0, "", 2);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.OUTSUB3", 0, "", 3);
+
+	psMetadata *outSubSub = psMetadataAlloc();
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.OUTSUB1", 0, "", 1);
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.OUTSUB2", 0, "", 2);
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.OUTSUB3", 0, "", 3);
+	psMetadataAddMetadata (outSub, PS_LIST_TAIL, "SUB", 0, "", outSubSub);
+
+	psMetadataAddMetadata (out, PS_LIST_TAIL, "SUB", 0, "", outSub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (inSub);
+	psFree (outSub);
+	psFree (inSubSub);
+	psFree (outSubSub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+
+    // overlay two metadatas, folder in input & output, matched elements
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *inSub = psMetadataAlloc();
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 1);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 2);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 3);
+	psMetadataAddMetadata (in, PS_LIST_TAIL, "SUB", 0, "", inSub);
+
+	psMetadata *outSub = psMetadataAlloc();
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 4);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 5);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 6);
+	psMetadataAddMetadata (out, PS_LIST_TAIL, "SUB", 0, "", outSub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (inSub);
+	psFree (outSub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+
+    // overlay two metadatas, folder and subfolders in input & output, no-matched elements
+    {
+	psMemId id = psMemGetId();
+	psMetadata *in = psMetadataAlloc();
+	psMetadata *out = psMetadataAlloc();
+
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN1", 0, "", 1);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN2", 0, "", 2);
+	psMetadataAddS32 (in, PS_LIST_TAIL, "TEST.IN3", 0, "", 3);
+
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT1", 0, "", 1);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT2", 0, "", 2);
+	psMetadataAddS32 (out, PS_LIST_TAIL, "TEST.OUT3", 0, "", 3);
+
+	psMetadata *inSub = psMetadataAlloc();
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 1);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 2);
+	psMetadataAddS32 (inSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 3);
+
+	psMetadata *inSubSub = psMetadataAlloc();
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 1);
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 2);
+	psMetadataAddS32 (inSubSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 3);
+	psMetadataAddMetadata (inSub, PS_LIST_TAIL, "SUB", 0, "", inSubSub);
+
+	psMetadataAddMetadata (in, PS_LIST_TAIL, "SUB", 0, "", inSub);
+
+	psMetadata *outSub = psMetadataAlloc();
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 4);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 5);
+	psMetadataAddS32 (outSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 6);
+
+	psMetadata *outSubSub = psMetadataAlloc();
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.SUB1", 0, "", 4);
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.SUB2", 0, "", 5);
+	psMetadataAddS32 (outSubSub, PS_LIST_TAIL, "TEST.SUB3", 0, "", 6);
+	psMetadataAddMetadata (outSub, PS_LIST_TAIL, "SUB", 0, "", outSubSub);
+
+	psMetadataAddMetadata (out, PS_LIST_TAIL, "SUB", 0, "", outSub);
+
+	bool status = psMetadataOverlay (out, in);
+	psMetadataPrint (stderr, out, 1);
+
+	ok (status, "psMetadataOverlay : overlay two MDs");
+	psFree (in);
+	psFree (out);
+	psFree (inSub);
+	psFree (outSub);
+	psFree (inSubSub);
+	psFree (outSubSub);
+	ok(!psMemCheckLeaks (id, NULL, NULL, false), "no memory leaks");
+    }
+}
+