Backport to 3.7. (arangodb#14781)

neunhoef · KVS85 · web-flow · commit 9b489d2312e3 · 2021-09-20T18:19:15.000+03:00
Co-authored-by: Vadim &lt;vadim@arangodb.com&gt;
diff --git a/CHANGELOG b/CHANGELOG
@@ -1,8 +1,10 @@
 v3.7.15 (XXXX-XX-XX)
 --------------------
 
-* Fix active failover, so that the new host actually has working
-  foxx services. (BTS-558)
+* Fixed a bug for array indexes on update of documents (BTS-548).
+
+* Fix active failover, so that the new host actually has working foxx services 
+  (BTS-558).
 
 * Updated OpenSSL to 1.1.1l and OpenLDAP to 2.4.59.
 
diff --git a/arangod/RocksDBEngine/RocksDBVPackIndex.cpp b/arangod/RocksDBEngine/RocksDBVPackIndex.cpp
@@ -921,6 +921,15 @@ namespace {
 
       if (begin->shouldExpand &&
           first.isArray() && second.isArray()) {
+        if (first.length() != second.length()) {
+          // Nonequal length, so there is a difference!
+          // We have to play this carefully here. It is possible that the
+          // set of values found is the same, but we must err on the side
+          // of caution in this case and use the slow path. Note in
+          // particular that the following code returns `true`, if one
+          // of the arrays is empty, which is not correct!
+          return false;
+        }
         auto next = begin + 1;
         VPackArrayIterator it1(first), it2(second);
         while (it1.valid() && it2.valid()) {
diff --git a/tests/js/server/shell/shell-array-index-noncluster.js b/tests/js/server/shell/shell-array-index-noncluster.js
@@ -275,7 +275,75 @@ function arraySkiplistIndexSuite () {
       catch (err) {
         assertEqual(errors.ERROR_ARANGO_UNIQUE_CONSTRAINT_VIOLATED.code, err.errorNum);
       }
-    }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test: Test update of an array index where entries are removed:
+////////////////////////////////////////////////////////////////////////////////
+
+    testPersistentArrayIndexUpdates : function () {
+      collection.ensureIndex({type:"persistent", fields: ["a[*].b"], unique: true});
+
+      let meta = collection.insert({a: [{b:"xyz"}]});
+
+      try {
+        collection.insert({a: [{b:"xyz"}]});
+        fail();
+      }
+      catch (err) {
+        assertEqual(errors.ERROR_ARANGO_UNIQUE_CONSTRAINT_VIOLATED.code, err.errorNum);
+      }
+
+      collection.update(meta._key, {a: []});
+
+      let meta2 = collection.insert({a: [{b:"xyz"}]});  // must work again
+
+      try {
+        collection.insert({a: [{b:"xyz"}]});
+        fail();
+      }
+      catch (err) {
+        assertEqual(errors.ERROR_ARANGO_UNIQUE_CONSTRAINT_VIOLATED.code, err.errorNum);
+      }
+
+      collection.replace(meta2._key, {a: []});
+
+      collection.insert({a: [{b:"xyz"}]});  // must work again
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test: Test update of an array index where entries are changed:
+////////////////////////////////////////////////////////////////////////////////
+
+    testPersistentArrayIndexUpdates2 : function () {
+      collection.ensureIndex({type:"persistent", fields: ["a[*].b"], unique: true});
+
+      let meta = collection.insert({a: [{b:"xyz"}]});
+
+      try {
+        collection.insert({a: [{b:"xyz"}]});
+        fail();
+      }
+      catch (err) {
+        assertEqual(errors.ERROR_ARANGO_UNIQUE_CONSTRAINT_VIOLATED.code, err.errorNum);
+      }
+
+      collection.update(meta._key, {a: [{b:"123"}]});
+
+      let meta2 = collection.insert({a: [{b:"xyz"}]});  // must work again
+
+      try {
+        collection.insert({a: [{b:"xyz"}]});
+        fail();
+      }
+      catch (err) {
+        assertEqual(errors.ERROR_ARANGO_UNIQUE_CONSTRAINT_VIOLATED.code, err.errorNum);
+      }
+
+      collection.replace(meta2._key, {a: [{b:"456"}]});
+
+      collection.insert({a: [{b:"xyz"}]});  // must work again
+    },
 
   };
 }
