Add verify functions

[frangio]

Fixes #8

[Amxx]

getProof and getMultiProof automatically verify the proofs that they produced. IMO, this should be done using these new functions.

Otherwize looks good.

[Amxx]

For getProof the change is quite simple:

     // check proof
-    const hash = this.tree[treeIndex]!;
-    const impliedRoot = processProof(hash, proof);
-    if (!equalsBytes(impliedRoot, this.tree[0]!)) {
+    if (!this.verify(leaf, proof.map(bytesToHex))) {
       throw new Error('Unable to prove value');
     }

But for getMultiProof its quite more complex because we need the leaves in T format

     // check proof
-    const impliedRoot = processMultiProof(proof);
-    if (!equalsBytes(impliedRoot, this.tree[0]!)) {
+    if (!this.verifyMultiProof({
+      leaves: indices.map(i => this.values.find(e => e.treeIndex == i)!.value),
+      proof: proof.proof.map(bytesToHex),
+      proofFlags: proof.proofFlags,
+    })) {
       throw new Error('Unable to prove values');
     }

[frangio]

I implemented that suggestion but I refactored the code a little to avoid converting back and forth between string and Bytes.

[frangio]

Do you mean that maybe they shouldn't be private? Let's keep them private for now because they work on Bytes values and not on strings like the rest of the StandardMerkleTree interface.

Eventually I would be interested in making standard and core both work generically on both Bytes and strings.

[Amxx]

Do you mean that maybe they shouldn't be private?

I meant they should be private, which they are. My bad.

[Amxx]

Eventually I would be interested in making standard and core both work generically on both Bytes and strings.

I know we don't like dependencies, but IMO there is already a de-facto standard for that: https://github.com/ethers-io/ethers.js/blob/master/packages/bytes/src.ts/index.ts#L12

[duktig666]

Can I directly call a similar method in JS and keep it consistent with solidity

solidity Provides such a method

function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) internal pure returns (bool) {
    return processProof(proof, leaf) == root;
}

https://github.com/merkletreejs/merkletreejs/blob/master/src/MerkleTree.ts 也实现了类似的方法：

verify (proof: any[], targetNode: Buffer | string, root: Buffer | string):boolean {

}

const tree = StandardMerkleTree.of();

Can Tree call verify directly?

[duktig666]

tree. verify();