[bugfix] cache:put should never return null

adamretter · adamretter · commit 87004d746e06 · 2021-06-18T17:58:02.000+02:00
diff --git a/extensions/modules/cache/src/main/java/org/exist/xquery/modules/cache/Cache.java b/extensions/modules/cache/src/main/java/org/exist/xquery/modules/cache/Cache.java
@@ -57,7 +57,11 @@ public CacheConfig getConfig() {
 	}
 
     public Sequence put(final String key, final Sequence value) {
-	    return store.asMap().put(key, value);
+	    final Sequence previous = store.asMap().put(key, value);
+	    if (previous != null) {
+	        return previous;
+        }
+	    return Sequence.EMPTY_SEQUENCE;
     }
 
     public Sequence list(final String[] keys) throws XPathException {

Original file line number	Diff line number	Diff line change
`@@ -57,7 +57,11 @@ public CacheConfig getConfig() {`
`57`	`57`	`}`
`58`	`58`
`59`	`59`	`public Sequence put(final String key, final Sequence value) {`
`60`		`- return store.asMap().put(key, value);`
	`60`	`+ final Sequence previous = store.asMap().put(key, value);`
	`61`	`+ if (previous != null) {`
	`62`	`+ return previous;`
	`63`	`+ }`
	`64`	`+ return Sequence.EMPTY_SEQUENCE;`
`61`	`65`	`}`
`62`	`66`
`63`	`67`	`public Sequence list(final String[] keys) throws XPathException {`