Fix AreaStore's IDs persistence (#8888)

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Fix free ID function. Return first gap in map

1 files changed, 20 insertions, 9 deletions

diff --git a/src/unittest/test_areastore.cpp b/src/unittest/test_areastore.cpp
index a6d4706e4..691cd69d2 100644
--- a/src/unittest/test_areastore.cpp
+++ b/src/unittest/test_areastore.cpp
@@ -128,11 +128,11 @@ void TestAreaStore::testSerialization()
 	VectorAreaStore store;
 
 	Area a(v3s16(-1, 0, 1), v3s16(0, 1, 2));
-	a.data = "Area A";
+	a.data = "Area AA";
 	store.insertArea(&a);
 
 	Area b(v3s16(123, 456, 789), v3s16(32000, 100, 10));
-	b.data = "Area B";
+	b.data = "Area BB";
 	store.insertArea(&b);
 
 	std::ostringstream os;
@@ -143,20 +143,31 @@ void TestAreaStore::testSerialization()
 			"\x00\x02"  // Count
 			"\xFF\xFF\x00\x00\x00\x01"  // Area A min edge
 			"\x00\x00\x00\x01\x00\x02"  // Area A max edge
-			"\x00\x06"  // Area A data length
-			"Area A"  // Area A data
+			"\x00\x07"  // Area A data length
+			"Area AA"   // Area A data
 			"\x00\x7B\x00\x64\x00\x0A"  // Area B min edge (last two swapped with max edge for sorting)
 			"\x7D\x00\x01\xC8\x03\x15"  // Area B max edge (^)
-			"\x00\x06"  // Area B data length
-			"Area B",  // Area B data
+			"\x00\x07"  // Area B data length
+			"Area BB"   // Area B data
+			"\x00\x00\x00\x00"  // ID A = 0
+			"\x00\x00\x00\x01", // ID B = 1
 			1 + 2 +
-			6 + 6 + 2 + 6 +
-			6 + 6 + 2 + 6);
+			(6 + 6 + 2 + 7) * 2 + // min/max edge, length, data
+			2 * 4); // Area IDs
+
 	UASSERTEQ(const std::string &, str, str_wanted);
 
 	std::istringstream is(str);
 	store.deserialize(is);
 
-	UASSERTEQ(size_t, store.size(), 4);  // deserialize() doesn't clear the store
+	// deserialize() doesn't clear the store
+	// But existing IDs are overridden
+	UASSERTEQ(size_t, store.size(), 2);
+
+	Area c(v3s16(33, -2, -6), v3s16(4, 77, -76));
+	c.data = "Area CC";
+	store.insertArea(&c);
+
+	UASSERTEQ(u32, c.id, 2);
 }