feat(ctb): explicit throw in trie get

Small refactor that has MerkleTrie.get throw explicitly when an element
does not exist, rather than returning a non-existence boolean. Makes the
code much cleaner. We need to review this change very carefully.

.changeset/spicy-buckets-beam.md

+---
+'@eth-optimism/contracts-bedrock': minor
+---
+
+Refactors the MerkleTrie get function to throw explicitly instead of returning an existence boolean

packages/contracts-bedrock/.gas-snapshot

@@ -132,6 +132,27 @@ LegacyERC20ETH_Test:test_mint_doesNotExist_reverts() (gas: 10649)
 LegacyERC20ETH_Test:test_transferFrom_doesNotExist_reverts() (gas: 12887)
 LegacyERC20ETH_Test:test_transfer_doesNotExist_reverts() (gas: 10733)
 LegacyMessagePasser_Test:test_passMessageToL1_succeeds() (gas: 34518)
+MerkleTrie_Test:test_get_reverts_corruptedProof() (gas: 5686)
+MerkleTrie_Test:test_get_reverts_extraProofElements() (gas: 60560)
+MerkleTrie_Test:test_get_reverts_invalidDataRemainder() (gas: 35827)
+MerkleTrie_Test:test_get_reverts_invalidInternalNodeHash() (gas: 50763)
+MerkleTrie_Test:test_get_reverts_nonexistentKey1() (gas: 59624)
+MerkleTrie_Test:test_get_reverts_nonexistentKey2() (gas: 23359)
+MerkleTrie_Test:test_get_reverts_smallerPathThanKey1() (gas: 53476)
+MerkleTrie_Test:test_get_reverts_smallerPathThanKey2() (gas: 54913)
+MerkleTrie_Test:test_get_reverts_wrongKeyProof() (gas: 53844)
+MerkleTrie_Test:test_get_reverts_zeroBranchValueLength() (gas: 43222)
+MerkleTrie_Test:test_get_reverts_zeroLengthKey() (gas: 15886)
+MerkleTrie_Test:test_get_validProofSucceeds1() (gas: 61619)
+MerkleTrie_Test:test_get_validProofSucceeds10() (gas: 50546)
+MerkleTrie_Test:test_get_validProofSucceeds2() (gas: 71531)
+MerkleTrie_Test:test_get_validProofSucceeds3() (gas: 32779)
+MerkleTrie_Test:test_get_validProofSucceeds4() (gas: 23553)
+MerkleTrie_Test:test_get_validProofSucceeds5() (gas: 84215)
+MerkleTrie_Test:test_get_validProofSucceeds6() (gas: 72991)
+MerkleTrie_Test:test_get_validProofSucceeds7() (gas: 79670)
+MerkleTrie_Test:test_get_validProofSucceeds8() (gas: 50546)
+MerkleTrie_Test:test_get_validProofSucceeds9() (gas: 50501)
 OptimismMintableERC20_Test:test_bridge_succeeds() (gas: 7643)
 OptimismMintableERC20_Test:test_burn_notBridge_reverts() (gas: 11165)
 OptimismMintableERC20_Test:test_burn_succeeds() (gas: 51013)
@@ -150,23 +171,23 @@ OptimismPortalUpgradeable_Test:test_initialize_cannotInitImpl_reverts() (gas: 10
 OptimismPortalUpgradeable_Test:test_initialize_cannotInitProxy_reverts() (gas: 15833)
 OptimismPortalUpgradeable_Test:test_params_initValuesOnProxy_succeeds() (gas: 16011)
 OptimismPortalUpgradeable_Test:test_upgradeToAndCall_upgrading_succeeds() (gas: 180457)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 199728)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 202025)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 198791)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 201110)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalNotProven_reverts() (gas: 39656)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 197092)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onInsufficientGas_reverts() (gas: 197814)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onRecentWithdrawal_reverts() (gas: 177806)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReentrancy_reverts() (gas: 236200)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 237764)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_succeeds() (gas: 229467)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 332148)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 193816)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 83542)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 196155)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onInsufficientGas_reverts() (gas: 196877)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onRecentWithdrawal_reverts() (gas: 176869)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReentrancy_reverts() (gas: 235239)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 236849)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_succeeds() (gas: 228530)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 331166)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 192879)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 83498)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidWithdrawalProof_reverts() (gas: 135228)
 OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onSelfCall_reverts() (gas: 50732)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() (gas: 136758)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProveChangedOutputRoot_succeeds() (gas: 277079)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProve_reverts() (gas: 189072)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_succeeds() (gas: 179324)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProveChangedOutputRoot_succeeds() (gas: 275227)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProve_reverts() (gas: 188157)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_succeeds() (gas: 178344)
 OptimismPortal_Test:test_constructor_succeeds() (gas: 17277)
 OptimismPortal_Test:test_depositTransaction_contractCreation_reverts() (gas: 14267)
 OptimismPortal_Test:test_depositTransaction_createWithZeroValueForContract_succeeds() (gas: 76662)

packages/contracts-bedrock/contracts/libraries/trie/SecureMerkleTrie.sol

@@ -40,14 +40,13 @@ library SecureMerkleTrie {
      * @param _proof Merkle trie inclusion proof for the key.
      * @param _root  Known root of the Merkle trie.
      *
-     * @return Whether or not the key exists.
      * @return Value of the key if it exists.
      */
     function get(
         bytes memory _key,
         bytes[] memory _proof,
         bytes32 _root
-    ) internal pure returns (bool, bytes memory) {
+    ) internal pure returns (bytes memory) {
         bytes memory key = _getSecureKey(_key);
         return MerkleTrie.get(key, _proof, _root);
     }

packages/contracts-bedrock/contracts/test/OptimismPortal.t.sol

@@ -362,10 +362,10 @@ contract OptimismPortal_FinalizeWithdrawal_Test is Portal_Initializer {
 
     // Test: proveWithdrawalTransaction reverts if the proof is invalid due to non-existence of
     // the withdrawal.
-    function test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() external {
+    function test_proveWithdrawalTransaction_onInvalidWithdrawalProof_reverts() external {
         // modify the default test values to invalidate the proof.
         _defaultTx.data = hex"abcd";
-        vm.expectRevert("OptimismPortal: invalid withdrawal inclusion proof");
+        vm.expectRevert("MerkleTrie: path remainder must share all nibbles with key");
         op.proveWithdrawalTransaction(
             _defaultTx,
             _proposedOutputIndex,