Include checkpoints by default in SecureTrie.copy

CHANGELOG.md

@@ -30,6 +30,10 @@ See the [docs](https://github.com/ethereumjs/merkle-patricia-tree/tree/master/do
 
 `getRaw`, `putRaw` and `delRaw` were deprecated in `v3.0.0` and have been removed from this release. Instead, please use `trie.db.get`, `trie.db.put`, and `trie.db.del`. If using a `SecureTrie` or `CheckpointTrie`, use `trie._maindb` to override the checkpointing mechanism and interact directly with the db.
 
+#### SecureTrie.copy
+
+`SecureTrie.copy` now includes checkpoint metadata by default. To maintain original behavior of _not_ copying checkpoint state, pass `false` to param `includeCheckpoints`.
+
 ### Changed
 
 - Convert trieNode to ES6 class ([#71](https://github.com/ethereumjs/merkle-patricia-tree/pull/71))
@@ -42,6 +46,7 @@ See the [docs](https://github.com/ethereumjs/merkle-patricia-tree/tree/master/do
 - Use `Nibbles` type for `number[]` ([#115](https://github.com/ethereumjs/merkle-patricia-tree/pull/115))
 - Upgrade ethereumjs-util to 7.0.0 / Upgrade level-mem to 5.0.1 ([#116](https://github.com/ethereumjs/merkle-patricia-tree/pull/116))
 - Create dual ES5 and ES2017 builds ([#117](https://github.com/ethereumjs/merkle-patricia-tree/pull/117))
+- Include checkpoints by default in SecureTrie.copy ([#119](https://github.com/ethereumjs/merkle-patricia-tree/pull/119))
 
 ### Added
 

src/checkpointTrie.ts

@@ -81,13 +81,10 @@ export class CheckpointTrie extends BaseTrie {
   }
 
   /**
-   * Returns a copy of the underlying trie with the interface
-   * of CheckpointTrie. If during a checkpoint, the copy will
-   * contain the checkpointing metadata (incl. reference to the same scratch).
-   * @param {boolean} includeCheckpoints - If true and during a checkpoint, the copy will
-   * contain the checkpointing metadata and will use the same scratch as underlying db.
+   * Returns a copy of the underlying trie with the interface of CheckpointTrie.
+   * @param {boolean} includeCheckpoints - If true and during a checkpoint, the copy will contain the checkpointing metadata and will use the same scratch as underlying db.
    */
-  copy(includeCheckpoints: boolean = true): CheckpointTrie {
+  copy(includeCheckpoints = true): CheckpointTrie {
     const db = this._mainDB.copy()
     const trie = new CheckpointTrie(db._leveldb, this.root)
     if (includeCheckpoints && this.isCheckpoint) {

src/secure.ts

@@ -24,8 +24,12 @@ export class SecureTrie extends CheckpointTrie {
     return super.verifyProof(rootHash, hash, proof)
   }
 
-  copy(): SecureTrie {
-    const trie = super.copy(false)
+  /**
+   * Returns a copy of the underlying trie with the interface of SecureTrie.
+   * @param {boolean} includeCheckpoints - If true and during a checkpoint, the copy will contain the checkpointing metadata and will use the same scratch as underlying db.
+   */
+  copy(includeCheckpoints = true): SecureTrie {
+    const trie = super.copy(includeCheckpoints)
     const db = trie.db.copy()
     return new SecureTrie(db._leveldb, this.root)
   }

test/secure.spec.ts

@@ -124,3 +124,29 @@ tape('secure tests should not crash', async function (t) {
   await trie.put(gk, g)
   t.end()
 })
+
+tape('SecureTrie.copy', function (it) {
+  it.test('created copy includes values added after checkpoint', async function (t) {
+    const trie = new SecureTrie()
+
+    await trie.put(Buffer.from('key1'), Buffer.from('value1'))
+    trie.checkpoint()
+    await trie.put(Buffer.from('key2'), Buffer.from('value2'))
+    const trieCopy = trie.copy()
+    const value = await trieCopy.get(Buffer.from('key2'))
+    t.equal(value.toString(), 'value2')
+    t.end()
+  })
+
+  it.test('created copy includes values added before checkpoint', async function (t) {
+    const trie = new SecureTrie()
+
+    await trie.put(Buffer.from('key1'), Buffer.from('value1'))
+    trie.checkpoint()
+    await trie.put(Buffer.from('key2'), Buffer.from('value2'))
+    const trieCopy = trie.copy()
+    const value = await trieCopy.get(Buffer.from('key1'))
+    t.equal(value.toString(), 'value1')
+    t.end()
+  })
+})