From ee90f4b242bd78d696c6018ba8b78bce263ddfca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Germ=C3=A1n=20Mart=C3=ADnez?= <germaga92@gmail.com>
Date: Tue, 23 Aug 2022 23:34:23 +0200
Subject: [PATCH 1/2] Make executeTransaction immutable

---
 packages/safe-core-sdk/src/Safe.ts | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/packages/safe-core-sdk/src/Safe.ts b/packages/safe-core-sdk/src/Safe.ts
index b95b1236a..4605a700c 100644
--- a/packages/safe-core-sdk/src/Safe.ts
+++ b/packages/safe-core-sdk/src/Safe.ts
@@ -605,20 +605,25 @@ class Safe {
     safeTransaction: SafeTransaction,
     options?: TransactionOptions
   ): Promise<TransactionResult> {
-    const txHash = await this.getTransactionHash(safeTransaction)
+    const signedSafeTransaction = await this.createTransaction(safeTransaction.data)
+    safeTransaction.signatures.forEach((signature) => {
+      signedSafeTransaction.addSignature(signature)
+    })
+
+    const txHash = await this.getTransactionHash(signedSafeTransaction)
     const ownersWhoApprovedTx = await this.getOwnersWhoApprovedTx(txHash)
     for (const owner of ownersWhoApprovedTx) {
-      safeTransaction.addSignature(generatePreValidatedSignature(owner))
+      signedSafeTransaction.addSignature(generatePreValidatedSignature(owner))
     }
     const owners = await this.getOwners()
     const signerAddress = await this.#ethAdapter.getSignerAddress()
     if (owners.includes(signerAddress)) {
-      safeTransaction.addSignature(generatePreValidatedSignature(signerAddress))
+      signedSafeTransaction.addSignature(generatePreValidatedSignature(signerAddress))
     }
 
     const threshold = await this.getThreshold()
-    if (threshold > safeTransaction.signatures.size) {
-      const signaturesMissing = threshold - safeTransaction.signatures.size
+    if (threshold > signedSafeTransaction.signatures.size) {
+      const signaturesMissing = threshold - signedSafeTransaction.signatures.size
       throw new Error(
         `There ${signaturesMissing > 1 ? 'are' : 'is'} ${signaturesMissing} signature${
           signaturesMissing > 1 ? 's' : ''
@@ -626,7 +631,7 @@ class Safe {
       )
     }
 
-    const value = BigNumber.from(safeTransaction.data.value)
+    const value = BigNumber.from(signedSafeTransaction.data.value)
     if (!value.isZero()) {
       const balance = await this.getBalance()
       if (value.gt(BigNumber.from(balance))) {
@@ -637,7 +642,7 @@ class Safe {
     if (options?.gas && options?.gasLimit) {
       throw new Error('Cannot specify gas and gasLimit together in transaction options')
     }
-    const txResponse = await this.#contractManager.safeContract.execTransaction(safeTransaction, {
+    const txResponse = await this.#contractManager.safeContract.execTransaction(signedSafeTransaction, {
       from: signerAddress,
       ...options
     })

From c40f96b59e4aaaf06b4ff400a9eb46bd31192e32 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Germ=C3=A1n=20Mart=C3=ADnez?= <germaga92@gmail.com>
Date: Tue, 23 Aug 2022 23:41:18 +0200
Subject: [PATCH 2/2] Tests executeTransaction immutability

---
 packages/safe-core-sdk/tests/execution.test.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packages/safe-core-sdk/tests/execution.test.ts b/packages/safe-core-sdk/tests/execution.test.ts
index efa14132b..11ac4fba1 100644
--- a/packages/safe-core-sdk/tests/execution.test.ts
+++ b/packages/safe-core-sdk/tests/execution.test.ts
@@ -188,7 +188,10 @@ describe('Transactions execution', () => {
         data: '0x'
       }
       const tx = await safeSdk1.createTransaction(txDataPartial)
+      const initNumSignatures = tx.signatures.size
       const txResponse = await safeSdk1.executeTransaction(tx)
+      const finalNumSignatures = tx.signatures.size
+      chai.expect(initNumSignatures).to.be.eq(finalNumSignatures)
       await waitSafeTxReceipt(txResponse)
       const safeFinalBalance = await safeSdk1.getBalance()
       chai