1 files changed, 33 insertions, 10 deletions
diff --git a/ext/bg/js/dictionary.js b/ext/bg/js/dictionary.js
index 1bc3c93c..bffa7afa 100644
--- a/ext/bg/js/dictionary.js
+++ b/ext/bg/js/dictionary.js
@@ -16,7 +16,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-/*global utilSetEqual, utilSetIntersection, apiTemplateRender*/
+/*global apiTemplateRender*/
 
 function dictEnabledSet(options) {
     const enabledDictionaryMap = new Map();
@@ -145,6 +145,30 @@ function dictTermsGroup(definitions, dictionaries) {
     return dictTermsSort(results);
 }
 
+function dictAreSetsEqual(set1, set2) {
+    if (set1.size !== set2.size) {
+        return false;
+    }
+
+    for (const value of set1) {
+        if (!set2.has(value)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+function dictGetSetIntersection(set1, set2) {
+    const result = [];
+    for (const value of set1) {
+        if (set2.has(value)) {
+            result.push(value);
+        }
+    }
+    return result;
+}
+
 function dictTermsMergeBySequence(definitions, mainDictionary) {
     const sequencedDefinitions = new Map();
     const nonSequencedDefinitions = [];
@@ -262,16 +286,15 @@ function dictTermsMergeByGloss(result, definitions, appendTo=null, mergedIndices
     }
 
     for (const definition of definitionsByGloss.values()) {
-        definition.only = [];
-        if (!utilSetEqual(definition.expression, resultExpressionSet)) {
-            for (const expression of utilSetIntersection(definition.expression, resultExpressionSet)) {
-                definition.only.push(expression);
-            }
+        const only = [];
+        const expressionSet = definition.expression;
+        const readingSet = definition.reading;
+        definition.only = only;
+        if (!dictAreSetsEqual(expressionSet, resultExpressionSet)) {
+            only.push(...dictGetSetIntersection(expressionSet, resultExpressionSet));
         }
-        if (!utilSetEqual(definition.reading, resultReadingSet)) {
-            for (const reading of utilSetIntersection(definition.reading, resultReadingSet)) {
-                definition.only.push(reading);
-            }
+        if (!dictAreSetsEqual(readingSet, resultReadingSet)) {
+            only.push(...dictGetSetIntersection(readingSet, resultReadingSet));
         }
     }