Merge branch 'dev' into acl-log-set-params

.gitignore

@@ -1,7 +1,8 @@
 # Dependencies
 node_modules/
 
-# Yarn lock files
+# Lock files
+package-lock.json
 yarn.lock
 
 # coverage

contracts/acl/ACLSyntaxSugar.sol

@@ -28,6 +28,10 @@ contract ACLSyntaxSugar {
         return arr(uint256(_a), _b, _c);
     }
 
+    function arr(address _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
+        return arr(uint256(_a), _b, _c, _d);
+    }
+
     function arr(address _a, uint256 _b) internal pure returns (uint256[] r) {
         return arr(uint256(_a), uint256(_b));
     }

contracts/common/Initializable.sol

@@ -5,9 +5,10 @@
 pragma solidity ^0.4.18;
 
 import "../apps/AppStorage.sol";
+import "../common/TimeHelpers.sol";
 
 
-contract Initializable is AppStorage {
+contract Initializable is AppStorage, TimeHelpers {
     modifier onlyInit {
         require(initializationBlock == 0);
         _;
@@ -31,13 +32,4 @@ contract Initializable is AppStorage {
     function initialized() internal onlyInit {
         initializationBlock = getBlockNumber();
     }
-
-    /**
-    * @dev Returns the current block number.
-    *      Using a function rather than `block.number` allows us to easily mock the block number in
-    *      tests.
-    */
-    function getBlockNumber() internal view returns (uint256) {
-        return block.number;
-    }
 }

contracts/common/TimeHelpers.sol

@@ -0,0 +1,48 @@
+/*
+ * SPDX-License-Identitifer:    MIT
+ */
+
+pragma solidity ^0.4.18;
+
+import "./Uint256Helpers.sol";
+
+
+contract TimeHelpers {
+    using Uint256Helpers for uint256;
+
+    /**
+    * @dev Returns the current block number.
+    *      Using a function rather than `block.number` allows us to easily mock the block number in
+    *      tests.
+    */
+    function getBlockNumber() internal view returns (uint256) {
+        return block.number;
+    }
+
+    /**
+    * @dev Returns the current block number, converted to uint64.
+    *      Using a function rather than `block.number` allows us to easily mock the block number in
+    *      tests.
+    */
+    function getBlockNumber64() internal view returns (uint64) {
+        return getBlockNumber().toUint64();
+    }
+
+    /**
+    * @dev Returns the current timestamp.
+    *      Using a function rather than `now` allows us to easily mock it in
+    *      tests.
+    */
+    function getTimestamp() internal view returns (uint256) {
+        return now;
+    }
+
+    /**
+    * @dev Returns the current timestamp, covnerted to uint64.
+    *      Using a function rather than `now` allows us to easily mock it in
+    *      tests.
+    */
+    function getTimestamp64() internal view returns (uint64) {
+        return getTimestamp().toUint64();
+    }
+}

contracts/common/Uint256Helpers.sol

@@ -0,0 +1,11 @@
+pragma solidity ^0.4.18;
+
+
+library Uint256Helpers {
+    uint256 public constant MAX_UINT64 = uint64(-1);
+
+    function toUint64(uint256 a) internal pure returns (uint64) {
+        require(a <= MAX_UINT64);
+        return uint64(a);
+    }
+}