Repair incorrect deduction of max fieldNo.

2 files changed, 4 insertions, 4 deletions

diff --git a/vsm/src/tests/document/document.cpp b/vsm/src/tests/document/document.cpp
index bff9294979e..12b321f7c80 100644
--- a/vsm/src/tests/document/document.cpp
+++ b/vsm/src/tests/document/document.cpp
@@ -76,7 +76,7 @@ DocumentTest::testStorageDocument()
 void DocumentTest::testStringFieldIdTMap()
 {
     StringFieldIdTMap m;
-    EXPECT_EQUAL(1u, m.highestFieldNo());
+    EXPECT_EQUAL(0u, m.highestFieldNo());
     EXPECT_TRUE(StringFieldIdTMap::npos == m.fieldNo("unknown"));
     m.add("f1");
     EXPECT_EQUAL(0u, m.fieldNo("f1"));
diff --git a/vsm/src/vespa/vsm/common/document.cpp b/vsm/src/vespa/vsm/common/document.cpp
index 7939391a503..94aa1a0909b 100644
--- a/vsm/src/vespa/vsm/common/document.cpp
+++ b/vsm/src/vespa/vsm/common/document.cpp
@@ -58,11 +58,11 @@ size_t StringFieldIdTMap::highestFieldNo() const
 {
   size_t maxFNo(0);
   for (const auto & field : _map) {
-    if (field.second > maxFNo) {
-      maxFNo = field.second;
+    if (field.second >= maxFNo) {
+      maxFNo = field.second + 1;
     }
   }
-  return maxFNo+1;
+  return maxFNo;
 }
 
 Document::~Document() { }