random walk: include starting node into returned path

java/src/main/java/org/softwareheritage/graph/algo/Traversal.java

@@ -288,9 +288,9 @@ public class Traversal {
      * that no suitable path have been found
      */
     public <T> ArrayList<Long> randomWalk(long srcNodeId, T dst, int retries) {
+        long curNodeId = srcNodeId;
         ArrayList<Long> path = new ArrayList<Long>();
         this.nbEdgesAccessed = 0;
-        long curNodeId = srcNodeId;
         boolean found;
 
         if (retries < 0) {
@@ -298,6 +298,7 @@ public class Traversal {
         }
 
         while (true) {
+            path.add(curNodeId);
             long nbNeighbors = graph.degree(curNodeId, useTransposed);
             if (nbNeighbors == 0) {
                 found = false;
@@ -307,9 +308,8 @@ public class Traversal {
             Iterator<Long> successors = neighbors.iterator();
 
             curNodeId = randomPick(successors, nbNeighbors);
-            path.add(curNodeId);
-
             if (isDstNode(curNodeId, dst)) {
+                path.add(curNodeId);
                 found = true;
                 break;
             }

swh/graph/tests/test_api_client.py

@@ -110,11 +110,10 @@ def test_random_walk(graph_client):
     the dataset, and only check the final node of the path (i.e., the origin)
 
     """
-    actual = list(graph_client.random_walk(
-        'swh:1:cnt:0000000000000000000000000000000000000001', 'ori',
-        direction='backward',
-    ))
+    src = 'swh:1:cnt:0000000000000000000000000000000000000001'
+    actual = list(graph_client.random_walk(src, 'ori', direction='backward'))
     expected_root = 'swh:1:ori:0000000000000000000000000000000000000021'
+    assert actual[0] == src
     assert actual[-1] == expected_root