From 508766d2f2dd072b29769db9dff4a5fc20ed4cc0 Mon Sep 17 00:00:00 2001
From: Sebastian Messmer <messmer@cryfs.org>
Date: Wed, 13 Jul 2016 00:22:35 +0200
Subject: [PATCH] Fix traversal and add test cases

---
 .../datatreestore/impl/LeafTraverser.cpp      |  5 ++--
 .../DataTreeTest_TraverseLeaves.cpp           | 26 +++++++++++++++++++
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/src/blobstore/implementations/onblocks/datatreestore/impl/LeafTraverser.cpp b/src/blobstore/implementations/onblocks/datatreestore/impl/LeafTraverser.cpp
index f3f0accc..1840e39c 100644
--- a/src/blobstore/implementations/onblocks/datatreestore/impl/LeafTraverser.cpp
+++ b/src/blobstore/implementations/onblocks/datatreestore/impl/LeafTraverser.cpp
@@ -32,14 +32,15 @@ namespace blobstore {
                 //     numLeaves<beginIndex<endIndex, numLeaves<beginIndex=endIndex
 
                 uint32_t maxLeavesForDepth = _maxLeavesForTreeDepth(root->depth());
+                bool increaseTreeDepth = endIndex > maxLeavesForDepth;
 
-                _traverseExistingSubtree(root.get(), std::min(beginIndex, maxLeavesForDepth), std::min(endIndex, maxLeavesForDepth), 0, false, onExistingLeaf, onCreateLeaf, onBacktrackFromSubtree);
+                _traverseExistingSubtree(root.get(), std::min(beginIndex, maxLeavesForDepth), std::min(endIndex, maxLeavesForDepth), 0, increaseTreeDepth, onExistingLeaf, onCreateLeaf, onBacktrackFromSubtree);
 
                 // If the traversal goes too far right for a tree this depth, increase tree depth by one and continue traversal.
                 // This is recursive, i.e. will be repeated if the tree is still not deep enough.
                 // We don't increase to the full needed tree depth in one step, because we want the traversal to go as far as possible
                 // and only then increase the depth - this causes the tree to be in consistent shape (balanced) for longer.
-                if (endIndex > maxLeavesForDepth) {
+                if (increaseTreeDepth) {
                     // TODO Test cases that increase tree depth by 0, 1, 2, ... levels
                     auto newRoot = _increaseTreeDepth(std::move(root));
                     return traverseAndReturnRoot(std::move(newRoot), std::max(beginIndex, maxLeavesForDepth), endIndex, onExistingLeaf, onCreateLeaf, onBacktrackFromSubtree);
diff --git a/test/blobstore/implementations/onblocks/datatreestore/DataTreeTest_TraverseLeaves.cpp b/test/blobstore/implementations/onblocks/datatreestore/DataTreeTest_TraverseLeaves.cpp
index 10fc875f..d0f8a931 100644
--- a/test/blobstore/implementations/onblocks/datatreestore/DataTreeTest_TraverseLeaves.cpp
+++ b/test/blobstore/implementations/onblocks/datatreestore/DataTreeTest_TraverseLeaves.cpp
@@ -389,4 +389,30 @@ TEST_F(DataTreeTest_TraverseLeaves, TraverseMiddlePartOfFourLevelTree) {
   TraverseLeaves(root.get(), nodeStore->layout().maxChildrenPerInnerNode()+5, 2*nodeStore->layout().maxChildrenPerInnerNode()*nodeStore->layout().maxChildrenPerInnerNode() + nodeStore->layout().maxChildrenPerInnerNode() -1);
 }
 
+TEST_F(DataTreeTest_TraverseLeaves, LastLeafIsAlreadyResizedInCallback) {
+  auto root = CreateLeaf();
+  root->flush();
+  auto tree = treeStore.load(root->key()).value();
+  tree->traverseLeaves(0, 2, [this] (uint32_t leafIndex, DataLeafNode *leaf) {
+      if (leafIndex == 0) {
+        EXPECT_EQ(nodeStore->layout().maxBytesPerLeaf(), leaf->numBytes());
+      } else {
+        EXPECT_TRUE(false) << "only two nodes";
+      }
+  }, [this] (uint32_t /*nodeIndex*/) -> Data {
+      return Data(1);
+  });
+}
+
+TEST_F(DataTreeTest_TraverseLeaves, LastLeafIsAlreadyResizedInCallback_TwoLevel) {
+  auto root = CreateFullTwoLevelWithLastLeafSize(5);
+  root->flush();
+  auto tree = treeStore.load(root->key()).value();
+  tree->traverseLeaves(0, nodeStore->layout().maxChildrenPerInnerNode()+1, [this] (uint32_t leafIndex, DataLeafNode *leaf) {
+      EXPECT_EQ(nodeStore->layout().maxBytesPerLeaf(), leaf->numBytes());
+  }, [this] (uint32_t /*nodeIndex*/) -> Data {
+      return Data(1);
+  });
+}
+
 //TODO Refactor the test cases that are too long