display empty R vector as '[]'

thurka · thurka · commit 1ac67799e6e1 · 2020-06-17T11:37:43.000+02:00
diff --git a/visualvm/heapviewer.truffle/src/org/graalvm/visualvm/heapviewer/truffle/lang/r/RDetailsProvider.java b/visualvm/heapviewer.truffle/src/org/graalvm/visualvm/heapviewer/truffle/lang/r/RDetailsProvider.java
@@ -165,8 +165,12 @@ public String getDetailsString(String className, Instance instance, Heap heap) {
             Integer len = (Integer) instance.getValueOfField("length"); // NOI18N
 
             if (stride != null && start != null & len != null) {
+                int length = len.intValue();
+                if (length == 0) {  // empty vector
+                    return "[]";
+                }
                 if (stride.intValue() == 1) {
-                    int end = start.intValue() + len.intValue()-1;
+                    int end = start.intValue() + length-1;
                     return "["+start.intValue()+":"+end+"]";
                 }
             }

Original file line number	Diff line number	Diff line change
`@@ -165,8 +165,12 @@ public String getDetailsString(String className, Instance instance, Heap heap) {`
`165`	`165`	`Integer len = (Integer) instance.getValueOfField("length"); // NOI18N`
`166`	`166`
`167`	`167`	`if (stride != null && start != null & len != null) {`
	`168`	`+ int length = len.intValue();`
	`169`	`+ if (length == 0) { // empty vector`
	`170`	`+ return "[]";`
	`171`	`+ }`
`168`	`172`	`if (stride.intValue() == 1) {`
`169`		`- int end = start.intValue() + len.intValue()-1;`
	`173`	`+ int end = start.intValue() + length-1;`
`170`	`174`	`return "["+start.intValue()+":"+end+"]";`
`171`	`175`	`}`
`172`	`176`	`}`