From 8918181c47c837802cd47e58372861aa9d60feab Mon Sep 17 00:00:00 2001
From: Pavel Kalinnikov <pkalinnikov@google.com>
Date: Thu, 28 Apr 2022 15:06:37 +0100
Subject: [PATCH] Unexport helper from a public interface (#2720)

---
 client/log_client.go   | 16 +++++++++++++---
 client/log_verifier.go | 11 -----------
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/client/log_client.go b/client/log_client.go
index e92bdd5ee8..4083200912 100644
--- a/client/log_client.go
+++ b/client/log_client.go
@@ -26,6 +26,7 @@ import (
 	"github.com/google/trillian"
 	"github.com/google/trillian/client/backoff"
 	"github.com/google/trillian/types"
+	"github.com/transparency-dev/merkle"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )
@@ -231,7 +232,7 @@ func (c *LogClient) UpdateRoot(ctx context.Context) (*types.LogRootV1, error) {
 // It is best to call this method with a context that will timeout to avoid
 // waiting forever.
 func (c *LogClient) WaitForInclusion(ctx context.Context, data []byte) error {
-	leaf := c.BuildLeaf(data)
+	leaf := prepareLeaf(c.hasher, data)
 
 	// If a minimum merge delay has been configured, wait at least that long before
 	// starting to poll
@@ -305,7 +306,7 @@ func (c *LogClient) AddSequencedLeaves(ctx context.Context, dataByIndex map[int6
 		if want := indexes[0] + int64(i); index != want {
 			return fmt.Errorf("missing index in contiugous index range. got: %v, want: %v", index, want)
 		}
-		leaf := c.BuildLeaf(dataByIndex[index])
+		leaf := prepareLeaf(c.hasher, dataByIndex[index])
 		leaf.LeafIndex = index
 		leaves = append(leaves, leaf)
 	}
@@ -319,10 +320,19 @@ func (c *LogClient) AddSequencedLeaves(ctx context.Context, dataByIndex map[int6
 // QueueLeaf adds a leaf to a Trillian log without blocking.
 // AlreadyExists is considered a success case by this function.
 func (c *LogClient) QueueLeaf(ctx context.Context, data []byte) error {
-	leaf := c.BuildLeaf(data)
+	leaf := prepareLeaf(c.hasher, data)
 	_, err := c.client.QueueLeaf(ctx, &trillian.QueueLeafRequest{
 		LogId: c.LogID,
 		Leaf:  leaf,
 	})
 	return err
 }
+
+// prepareLeaf returns a trillian.LogLeaf prepopulated with leaf data and hash.
+func prepareLeaf(hasher merkle.LogHasher, data []byte) *trillian.LogLeaf {
+	leafHash := hasher.HashLeaf(data)
+	return &trillian.LogLeaf{
+		LeafValue:      data,
+		MerkleLeafHash: leafHash,
+	}
+}
diff --git a/client/log_verifier.go b/client/log_verifier.go
index 3154e1412a..3e8ecfff11 100644
--- a/client/log_verifier.go
+++ b/client/log_verifier.go
@@ -89,14 +89,3 @@ func (c *LogVerifier) VerifyInclusionByHash(trusted *types.LogRootV1, leafHash [
 
 	return proof.VerifyInclusion(c.hasher, uint64(pf.LeafIndex), trusted.TreeSize, leafHash, pf.Hashes, trusted.RootHash)
 }
-
-// BuildLeaf runs the leaf hasher over data and builds a leaf.
-// TODO(pavelkalinnikov): This can be misleading as it creates a partially
-// filled LogLeaf. Consider returning a pair instead, or leafHash only.
-func (c *LogVerifier) BuildLeaf(data []byte) *trillian.LogLeaf {
-	leafHash := c.hasher.HashLeaf(data)
-	return &trillian.LogLeaf{
-		LeafValue:      data,
-		MerkleLeafHash: leafHash,
-	}
-}