From 8c7a34a604430374becc8367e30af475fdd0f79d Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Thu, 24 Oct 2019 19:19:52 +0200
Subject: [PATCH 1/8] Add Freezable contract

---
 .../protocol/contracts/common/Freezable.sol   |  36 ++++++
 .../contracts/common/test/FreezableTest.sol   |  24 ++++
 packages/protocol/test/common/freezable.ts    | 106 ++++++++++++++++++
 3 files changed, 166 insertions(+)
 create mode 100644 packages/protocol/contracts/common/Freezable.sol
 create mode 100644 packages/protocol/contracts/common/test/FreezableTest.sol
 create mode 100644 packages/protocol/test/common/freezable.ts

diff --git a/packages/protocol/contracts/common/Freezable.sol b/packages/protocol/contracts/common/Freezable.sol
new file mode 100644
index 00000000000..e8f25db92eb
--- /dev/null
+++ b/packages/protocol/contracts/common/Freezable.sol
@@ -0,0 +1,36 @@
+pragma solidity ^0.5.3;
+
+
+contract Freezable {
+  bool public frozen;
+  address public freezer;
+
+  modifier onlyFreezer() {
+      require(msg.sender == freezer);
+      _;
+  }
+
+  modifier onlyWhenNotFrozen() {
+    if (!frozen) {
+        _;
+    }
+  }
+
+  modifier onlyWhenNotFrozenOrThrow() {
+    require(!frozen);
+    _;
+  }
+
+  function _setFreezer(address _freezer) internal {
+      freezer = _freezer;
+  }
+
+  function freeze() external onlyFreezer {
+      frozen = true;
+  }
+
+  function unfreeze() external onlyFreezer {
+      frozen = false;
+  }
+}
+
diff --git a/packages/protocol/contracts/common/test/FreezableTest.sol b/packages/protocol/contracts/common/test/FreezableTest.sol
new file mode 100644
index 00000000000..21c2efe23e2
--- /dev/null
+++ b/packages/protocol/contracts/common/test/FreezableTest.sol
@@ -0,0 +1,24 @@
+pragma solidity ^0.5.8;
+
+import "../Freezable.sol";
+
+
+contract FreezableTest is Freezable {
+    event FunctionCalled();
+
+    function setFreezer(address _freezer) external {
+        _setFreezer(_freezer);
+    }
+
+    function freezableFunction() external onlyWhenNotFrozen {
+        emit FunctionCalled();
+    }
+
+    function freezableFunctionWithThrow() external onlyWhenNotFrozenOrThrow {
+        emit FunctionCalled();
+    }
+
+    function nonfreezableFunction() external {
+        emit FunctionCalled();
+    }
+}
diff --git a/packages/protocol/test/common/freezable.ts b/packages/protocol/test/common/freezable.ts
new file mode 100644
index 00000000000..67889ba39fe
--- /dev/null
+++ b/packages/protocol/test/common/freezable.ts
@@ -0,0 +1,106 @@
+import { assertSameAddress, assertLogMatches2, assertRevert } from '@celo/protocol/lib/test-utils'
+import { FreezableTestInstance } from 'types'
+
+contract('Freezable', (accounts: string[]) => {
+  const FreezableTest = artifacts.require('FreezableTest')
+  let freezableTest: FreezableTestInstance
+
+  beforeEach(async () => {
+    freezableTest = await FreezableTest.new()
+    freezableTest.setFreezer(accounts[0])
+  })
+
+  describe('_setFreezer', () => {
+    it('should allow owner to change the freezer', async () => {
+      // _setFreezer is internal in Freezable, FreezableTest wraps around it with setFreezer
+      await freezableTest.setFreezer(accounts[1])
+      const freezer = await freezableTest.freezer()
+      assertSameAddress(freezer, accounts[1])
+    })
+  })
+
+  describe('when the contract is not frozen', () => {
+    it('should allow freezable functions to be called', async () => {
+      const resp = await freezableTest.freezableFunction()
+      assert.equal(resp.logs.length, 1)
+      const log = resp.logs[0]
+      assertLogMatches2(log, {
+        event: 'FunctionCalled',
+        args: {},
+      })
+    })
+
+    it('should allow freezable functions that throw to be called', async () => {
+      const resp = await freezableTest.freezableFunctionWithThrow()
+      assert.equal(resp.logs.length, 1)
+      const log = resp.logs[0]
+      assertLogMatches2(log, {
+        event: 'FunctionCalled',
+        args: {},
+      })
+    })
+
+    it('should allow non-freezable functions to be called', async () => {
+      const resp = await freezableTest.nonfreezableFunction()
+      assert.equal(resp.logs.length, 1)
+      const log = resp.logs[0]
+      assertLogMatches2(log, {
+        event: 'FunctionCalled',
+        args: {},
+      })
+    })
+  })
+
+  describe('freeze', () => {
+    it('should allow freezer to freeze the contract', async () => {
+      await freezableTest.freeze()
+      const frozen = await freezableTest.frozen()
+      assert.isTrue(frozen)
+    })
+
+    it('should not allow a non-freezer to freeze the contract', async () => {
+      await assertRevert(freezableTest.freeze({ from: accounts[1] }))
+    })
+  })
+
+  describe('unfreeze', () => {
+    beforeEach(async () => {
+      freezableTest.freeze()
+    })
+
+    it('should allow freezer to unfreeze the contract', async () => {
+      await freezableTest.unfreeze()
+      const frozen = await freezableTest.frozen()
+      assert.isFalse(frozen)
+    })
+
+    it('should not allow a non-freezer to unfreeze the contract', async () => {
+      await assertRevert(freezableTest.freeze({ from: accounts[1] }))
+    })
+  })
+
+  describe('when the contract is frozen', () => {
+    beforeEach(async () => {
+      await freezableTest.freeze()
+    })
+
+    it('should not run a freezable function', async () => {
+      const resp = await freezableTest.freezableFunction()
+      assert.equal(resp.logs.length, 0)
+    })
+
+    it('should revert a freezable function that throws', async () => {
+      await assertRevert(freezableTest.freezableFunctionWithThrow())
+    })
+
+    it('should not affect a non-freezable function', async () => {
+      const resp = await freezableTest.nonfreezableFunction()
+      assert.equal(resp.logs.length, 1)
+      const log = resp.logs[0]
+      assertLogMatches2(log, {
+        event: 'FunctionCalled',
+        args: {},
+      })
+    })
+  })
+})

From bf96502f57e77ecda7ff037ff415a088bb61c827 Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Thu, 24 Oct 2019 21:13:09 +0200
Subject: [PATCH 2/8] Enable freezing of the exchange

---
 packages/protocol/contracts/stability/Exchange.sol  | 10 +++++++++-
 .../contracts/stability/interfaces/IExchange.sol    |  1 +
 packages/protocol/migrations/09_exchange.ts         |  5 ++++-
 packages/protocol/test/stability/exchange.ts        | 13 +++++++++++++
 4 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/packages/protocol/contracts/stability/Exchange.sol b/packages/protocol/contracts/stability/Exchange.sol
index 5e0e457422e..0a4b90050bf 100644
--- a/packages/protocol/contracts/stability/Exchange.sol
+++ b/packages/protocol/contracts/stability/Exchange.sol
@@ -10,6 +10,7 @@ import "./interfaces/IStableToken.sol";
 import "../common/FractionUtil.sol";
 import "../common/Initializable.sol";
 import "../common/FixidityLib.sol";
+import "../common/Freezable.sol";
 import "../common/UsingRegistry.sol";
 
 
@@ -17,7 +18,7 @@ import "../common/UsingRegistry.sol";
  * @title Contract that allows to exchange StableToken for GoldToken and vice versa
  * using a Constant Product Market Maker Model
  */
-contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, ReentrancyGuard {
+contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, ReentrancyGuard, Freezable {
   using SafeMath for uint256;
   using FractionUtil for FractionUtil.Fraction;
   using FixidityLib for FixidityLib.Fraction;
@@ -89,6 +90,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
    */
   function initialize(
     address registryAddress,
+    address _freezer,
     address stableToken,
     uint256 _spread,
     uint256 _reserveFraction,
@@ -99,6 +101,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
     initializer
   {
     _transferOwnership(msg.sender);
+    setFreezer(_freezer);
     setRegistry(registryAddress);
     setStableToken(stableToken);
     setSpread(_spread);
@@ -123,6 +126,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
     bool sellGold
   )
     external
+    onlyWhenNotFrozenOrThrow
     updateBucketsIfNecessary
     nonReentrant
     returns (uint256)
@@ -254,6 +258,10 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
     emit MinimumReportsSet(newMininumReports);
   }
 
+  function setFreezer(address freezer) public onlyOwner {
+      _setFreezer(freezer);
+  }
+
   /**
     * @notice Allows owner to set the Stable Token address
     * @param newStableToken The new address for Stable Token
diff --git a/packages/protocol/contracts/stability/interfaces/IExchange.sol b/packages/protocol/contracts/stability/interfaces/IExchange.sol
index 8be29102eb3..b70d8250ecc 100644
--- a/packages/protocol/contracts/stability/interfaces/IExchange.sol
+++ b/packages/protocol/contracts/stability/interfaces/IExchange.sol
@@ -4,6 +4,7 @@ pragma solidity ^0.5.3;
 interface IExchange {
 
   function initialize(
+    address,
     address,
     address,
     uint256,
diff --git a/packages/protocol/migrations/09_exchange.ts b/packages/protocol/migrations/09_exchange.ts
index 0eedb8069f1..839d9c5c19e 100644
--- a/packages/protocol/migrations/09_exchange.ts
+++ b/packages/protocol/migrations/09_exchange.ts
@@ -8,8 +8,10 @@ import {
 import { config } from '@celo/protocol/migrationsConfig'
 import { toFixed } from '@celo/utils/lib/fixidity'
 import { ExchangeInstance, ReserveInstance, StableTokenInstance } from 'types'
+const truffle = require('@celo/protocol/truffle-config.js')
 
-const initializeArgs = async (): Promise<any[]> => {
+const initializeArgs = async (networkName: string): Promise<any[]> => {
+  const network: any = truffle.networks[networkName]
   const stableToken: StableTokenInstance = await getDeployedProxiedContract<StableTokenInstance>(
     'StableToken',
     artifacts
@@ -17,6 +19,7 @@ const initializeArgs = async (): Promise<any[]> => {
   return [
     config.registry.predeployedProxyAddress,
     stableToken.address,
+    network.from,
     toFixed(config.exchange.spread).toString(),
     toFixed(config.exchange.reserveFraction).toString(),
     config.exchange.updateFrequency,
diff --git a/packages/protocol/test/stability/exchange.ts b/packages/protocol/test/stability/exchange.ts
index eddd3b9183a..37b6ca843ed 100644
--- a/packages/protocol/test/stability/exchange.ts
+++ b/packages/protocol/test/stability/exchange.ts
@@ -119,6 +119,7 @@ contract('Exchange', (accounts: string[]) => {
     exchange = await Exchange.new()
     await exchange.initialize(
       registry.address,
+      accounts[0],
       stableToken.address,
       spread,
       reserveFraction,
@@ -139,6 +140,7 @@ contract('Exchange', (accounts: string[]) => {
       await assertRevert(
         exchange.initialize(
           registry.address,
+          accounts[0],
           stableToken.address,
           spread,
           reserveFraction,
@@ -792,5 +794,16 @@ contract('Exchange', (accounts: string[]) => {
         })
       })
     })
+
+    describe('when the contract is frozen', () => {
+      beforeEach(async () => {
+        await exchange.freeze()
+      })
+
+      it('should revert', async () => {
+        await goldToken.approve(exchange.address, 1000)
+        await assertRevert(exchange.exchange(1000, 1, true))
+      })
+    })
   })
 })

From 2975bb1b473053076cc4b1193257281f9313da4a Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Thu, 24 Oct 2019 21:25:55 +0200
Subject: [PATCH 3/8] Move Freezable to new baklava directory

---
 packages/protocol/contracts/{common => baklava}/Freezable.sol   | 0
 .../contracts/{common => baklava}/test/FreezableTest.sol        | 0
 packages/protocol/contracts/stability/Exchange.sol              | 2 +-
 packages/protocol/test/{common => baklava}/freezable.ts         | 0
 4 files changed, 1 insertion(+), 1 deletion(-)
 rename packages/protocol/contracts/{common => baklava}/Freezable.sol (100%)
 rename packages/protocol/contracts/{common => baklava}/test/FreezableTest.sol (100%)
 rename packages/protocol/test/{common => baklava}/freezable.ts (100%)

diff --git a/packages/protocol/contracts/common/Freezable.sol b/packages/protocol/contracts/baklava/Freezable.sol
similarity index 100%
rename from packages/protocol/contracts/common/Freezable.sol
rename to packages/protocol/contracts/baklava/Freezable.sol
diff --git a/packages/protocol/contracts/common/test/FreezableTest.sol b/packages/protocol/contracts/baklava/test/FreezableTest.sol
similarity index 100%
rename from packages/protocol/contracts/common/test/FreezableTest.sol
rename to packages/protocol/contracts/baklava/test/FreezableTest.sol
diff --git a/packages/protocol/contracts/stability/Exchange.sol b/packages/protocol/contracts/stability/Exchange.sol
index 0a4b90050bf..cd29f75dbeb 100644
--- a/packages/protocol/contracts/stability/Exchange.sol
+++ b/packages/protocol/contracts/stability/Exchange.sol
@@ -10,7 +10,7 @@ import "./interfaces/IStableToken.sol";
 import "../common/FractionUtil.sol";
 import "../common/Initializable.sol";
 import "../common/FixidityLib.sol";
-import "../common/Freezable.sol";
+import "../baklava/Freezable.sol";
 import "../common/UsingRegistry.sol";
 
 
diff --git a/packages/protocol/test/common/freezable.ts b/packages/protocol/test/baklava/freezable.ts
similarity index 100%
rename from packages/protocol/test/common/freezable.ts
rename to packages/protocol/test/baklava/freezable.ts

From 4a546f8aaec213637a896eaa8ace8e25001f7964 Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Fri, 25 Oct 2019 10:42:14 +0200
Subject: [PATCH 4/8] Add natspecs

---
 .../protocol/contracts/baklava/Freezable.sol    | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/packages/protocol/contracts/baklava/Freezable.sol b/packages/protocol/contracts/baklava/Freezable.sol
index e8f25db92eb..79878268257 100644
--- a/packages/protocol/contracts/baklava/Freezable.sol
+++ b/packages/protocol/contracts/baklava/Freezable.sol
@@ -5,32 +5,47 @@ contract Freezable {
   bool public frozen;
   address public freezer;
 
+  // onlyFreezer functions can only be called by the specified `freezer` address
   modifier onlyFreezer() {
       require(msg.sender == freezer);
       _;
   }
 
+  // onlyWhenNotFrozen functions can only be called when `frozen` is false, otherwise they are
+  // noops.
   modifier onlyWhenNotFrozen() {
     if (!frozen) {
         _;
     }
   }
 
+  // onlyWhenNotFrozenOrThrow functions can only be called when `frozen` is false, otherwise they
+  // will revert.
   modifier onlyWhenNotFrozenOrThrow() {
     require(!frozen);
     _;
   }
 
+  /**
+   * @notice Sets the address that is allowed to freeze/unfreeze the contract.
+   * @param _freezer The address that is allowed to freeze/unfree the contract
+   * @dev This function is `internal` and leaves its permissioning up to the inheriting contract.
+   */
   function _setFreezer(address _freezer) internal {
       freezer = _freezer;
   }
 
+  /**
+   * @notice Freezes the contract, disabling `onlyWhenNotFrozen` functions.
+   */
   function freeze() external onlyFreezer {
       frozen = true;
   }
 
+  /**
+   * @notice Unreezes the contract, enabling `onlyWhenNotFrozen` functions.
+   */
   function unfreeze() external onlyFreezer {
       frozen = false;
   }
 }
-

From 906d0508e391684a61c97d43b73976f5f0db015e Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Fri, 25 Oct 2019 10:43:38 +0200
Subject: [PATCH 5/8] Add comment

---
 packages/protocol/contracts/stability/Exchange.sol | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/protocol/contracts/stability/Exchange.sol b/packages/protocol/contracts/stability/Exchange.sol
index cd29f75dbeb..7b02d2d22fd 100644
--- a/packages/protocol/contracts/stability/Exchange.sol
+++ b/packages/protocol/contracts/stability/Exchange.sol
@@ -119,6 +119,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
    * transaction to succeed
    * @param sellGold `true` if gold is the sell token
    * @return The amount of buyToken that was transfered
+   * @dev This function can be frozen using the Freezable interface.
    */
   function exchange(
     uint256 sellAmount,

From cf91eebd3f3226893a3a9869e2473ec568245f1f Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Fri, 25 Oct 2019 21:54:39 +0200
Subject: [PATCH 6/8] Appease the linter

---
 .../protocol/contracts/baklava/Freezable.sol  | 12 ++++-----
 .../contracts/baklava/test/FreezableTest.sol  | 26 +++++++++----------
 .../protocol/contracts/stability/Exchange.sol |  2 +-
 3 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/packages/protocol/contracts/baklava/Freezable.sol b/packages/protocol/contracts/baklava/Freezable.sol
index 79878268257..16ed12bf405 100644
--- a/packages/protocol/contracts/baklava/Freezable.sol
+++ b/packages/protocol/contracts/baklava/Freezable.sol
@@ -7,15 +7,15 @@ contract Freezable {
 
   // onlyFreezer functions can only be called by the specified `freezer` address
   modifier onlyFreezer() {
-      require(msg.sender == freezer);
-      _;
+    require(msg.sender == freezer);
+    _;
   }
 
   // onlyWhenNotFrozen functions can only be called when `frozen` is false, otherwise they are
   // noops.
   modifier onlyWhenNotFrozen() {
     if (!frozen) {
-        _;
+      _;
     }
   }
 
@@ -32,20 +32,20 @@ contract Freezable {
    * @dev This function is `internal` and leaves its permissioning up to the inheriting contract.
    */
   function _setFreezer(address _freezer) internal {
-      freezer = _freezer;
+    freezer = _freezer;
   }
 
   /**
    * @notice Freezes the contract, disabling `onlyWhenNotFrozen` functions.
    */
   function freeze() external onlyFreezer {
-      frozen = true;
+    frozen = true;
   }
 
   /**
    * @notice Unreezes the contract, enabling `onlyWhenNotFrozen` functions.
    */
   function unfreeze() external onlyFreezer {
-      frozen = false;
+    frozen = false;
   }
 }
diff --git a/packages/protocol/contracts/baklava/test/FreezableTest.sol b/packages/protocol/contracts/baklava/test/FreezableTest.sol
index 21c2efe23e2..2888dcb0824 100644
--- a/packages/protocol/contracts/baklava/test/FreezableTest.sol
+++ b/packages/protocol/contracts/baklava/test/FreezableTest.sol
@@ -4,21 +4,21 @@ import "../Freezable.sol";
 
 
 contract FreezableTest is Freezable {
-    event FunctionCalled();
+  event FunctionCalled();
 
-    function setFreezer(address _freezer) external {
-        _setFreezer(_freezer);
-    }
+  function setFreezer(address _freezer) external {
+    _setFreezer(_freezer);
+  }
 
-    function freezableFunction() external onlyWhenNotFrozen {
-        emit FunctionCalled();
-    }
+  function freezableFunction() external onlyWhenNotFrozen {
+    emit FunctionCalled();
+  }
 
-    function freezableFunctionWithThrow() external onlyWhenNotFrozenOrThrow {
-        emit FunctionCalled();
-    }
+  function freezableFunctionWithThrow() external onlyWhenNotFrozenOrThrow {
+    emit FunctionCalled();
+  }
 
-    function nonfreezableFunction() external {
-        emit FunctionCalled();
-    }
+  function nonfreezableFunction() external {
+    emit FunctionCalled();
+  }
 }
diff --git a/packages/protocol/contracts/stability/Exchange.sol b/packages/protocol/contracts/stability/Exchange.sol
index 7b02d2d22fd..8d816e82a21 100644
--- a/packages/protocol/contracts/stability/Exchange.sol
+++ b/packages/protocol/contracts/stability/Exchange.sol
@@ -260,7 +260,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
   }
 
   function setFreezer(address freezer) public onlyOwner {
-      _setFreezer(freezer);
+    _setFreezer(freezer);
   }
 
   /**

From 7df038d4d7ccbc04b713a93ae65710afff67ba6d Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Mon, 28 Oct 2019 21:11:19 +0100
Subject: [PATCH 7/8] Order arguments correctly

---
 packages/protocol/migrations/09_exchange.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/protocol/migrations/09_exchange.ts b/packages/protocol/migrations/09_exchange.ts
index 96c3ab8888b..b0e1f4b97ef 100644
--- a/packages/protocol/migrations/09_exchange.ts
+++ b/packages/protocol/migrations/09_exchange.ts
@@ -18,8 +18,8 @@ const initializeArgs = async (networkName: string): Promise<any[]> => {
   )
   return [
     config.registry.predeployedProxyAddress,
-    stableToken.address,
     network.from,
+    stableToken.address,
     toFixed(config.exchange.spread).toString(),
     toFixed(config.exchange.reserveFraction).toString(),
     config.exchange.updateFrequency,

From e4b9d6392bb8c1f152401ab66e4386232af6503b Mon Sep 17 00:00:00 2001
From: Marcin Chrzanowski <martin@celo.org>
Date: Sat, 2 Nov 2019 00:23:21 +0100
Subject: [PATCH 8/8] Remove non-throwing modifier

---
 .../protocol/contracts/baklava/Freezable.sol  | 12 ++----------
 .../contracts/baklava/test/FreezableTest.sol  |  4 ----
 .../protocol/contracts/stability/Exchange.sol |  2 +-
 packages/protocol/test/baklava/freezable.ts   | 19 ++-----------------
 4 files changed, 5 insertions(+), 32 deletions(-)

diff --git a/packages/protocol/contracts/baklava/Freezable.sol b/packages/protocol/contracts/baklava/Freezable.sol
index 16ed12bf405..2d0a57a5c87 100644
--- a/packages/protocol/contracts/baklava/Freezable.sol
+++ b/packages/protocol/contracts/baklava/Freezable.sol
@@ -11,17 +11,9 @@ contract Freezable {
     _;
   }
 
-  // onlyWhenNotFrozen functions can only be called when `frozen` is false, otherwise they are
-  // noops.
+  // onlyWhenNotFrozen functions can only be called when `frozen` is false, otherwise they will
+  // revert.
   modifier onlyWhenNotFrozen() {
-    if (!frozen) {
-      _;
-    }
-  }
-
-  // onlyWhenNotFrozenOrThrow functions can only be called when `frozen` is false, otherwise they
-  // will revert.
-  modifier onlyWhenNotFrozenOrThrow() {
     require(!frozen);
     _;
   }
diff --git a/packages/protocol/contracts/baklava/test/FreezableTest.sol b/packages/protocol/contracts/baklava/test/FreezableTest.sol
index 2888dcb0824..23c5baf55fa 100644
--- a/packages/protocol/contracts/baklava/test/FreezableTest.sol
+++ b/packages/protocol/contracts/baklava/test/FreezableTest.sol
@@ -14,10 +14,6 @@ contract FreezableTest is Freezable {
     emit FunctionCalled();
   }
 
-  function freezableFunctionWithThrow() external onlyWhenNotFrozenOrThrow {
-    emit FunctionCalled();
-  }
-
   function nonfreezableFunction() external {
     emit FunctionCalled();
   }
diff --git a/packages/protocol/contracts/stability/Exchange.sol b/packages/protocol/contracts/stability/Exchange.sol
index 8d816e82a21..0291998717e 100644
--- a/packages/protocol/contracts/stability/Exchange.sol
+++ b/packages/protocol/contracts/stability/Exchange.sol
@@ -127,7 +127,7 @@ contract Exchange is IExchange, Initializable, Ownable, UsingRegistry, Reentranc
     bool sellGold
   )
     external
-    onlyWhenNotFrozenOrThrow
+    onlyWhenNotFrozen
     updateBucketsIfNecessary
     nonReentrant
     returns (uint256)
diff --git a/packages/protocol/test/baklava/freezable.ts b/packages/protocol/test/baklava/freezable.ts
index 67889ba39fe..1c7431a80f6 100644
--- a/packages/protocol/test/baklava/freezable.ts
+++ b/packages/protocol/test/baklava/freezable.ts
@@ -30,16 +30,6 @@ contract('Freezable', (accounts: string[]) => {
       })
     })
 
-    it('should allow freezable functions that throw to be called', async () => {
-      const resp = await freezableTest.freezableFunctionWithThrow()
-      assert.equal(resp.logs.length, 1)
-      const log = resp.logs[0]
-      assertLogMatches2(log, {
-        event: 'FunctionCalled',
-        args: {},
-      })
-    })
-
     it('should allow non-freezable functions to be called', async () => {
       const resp = await freezableTest.nonfreezableFunction()
       assert.equal(resp.logs.length, 1)
@@ -84,13 +74,8 @@ contract('Freezable', (accounts: string[]) => {
       await freezableTest.freeze()
     })
 
-    it('should not run a freezable function', async () => {
-      const resp = await freezableTest.freezableFunction()
-      assert.equal(resp.logs.length, 0)
-    })
-
-    it('should revert a freezable function that throws', async () => {
-      await assertRevert(freezableTest.freezableFunctionWithThrow())
+    it('should revert a freezable function', async () => {
+      await assertRevert(freezableTest.freezableFunction())
     })
 
     it('should not affect a non-freezable function', async () => {