Interface improvements for third parties (Synthetixio#514)

Author: justin j. moses

contracts/Synthetix.sol

@@ -172,9 +172,6 @@ contract Synthetix is IERC20, ExternStateToken, MixinResolver, ISynthetix {
         return _totalIssuedSynths(currencyKey, true);
     }
 
-    /**
-     * @notice Returns the currencyKeys of availableSynths for rate checking
-     */
     function availableCurrencyKeys() public view returns (bytes32[] memory) {
         bytes32[] memory currencyKeys = new bytes32[](availableSynths.length);
 
@@ -185,10 +182,7 @@ contract Synthetix is IERC20, ExternStateToken, MixinResolver, ISynthetix {
         return currencyKeys;
     }
 
-    /**
-     * @notice Returns the count of available synths in the system, which you can use to iterate availableSynths
-     */
-    function availableSynthCount() public view returns (uint) {
+    function availableSynthCount() external view returns (uint) {
         return availableSynths.length;
     }
 

contracts/interfaces/IDepot.sol

@@ -2,15 +2,27 @@ pragma solidity ^0.5.16;
 
 
 interface IDepot {
-    function exchangeEtherForSynths() external payable returns (uint);
+    // Views
+    function fundsWallet() external view returns (address payable);
 
-    function exchangeEtherForSynthsAtRate(uint guaranteedRate) external payable returns (uint);
+    function maxEthPurchase() external view returns (uint);
+
+    function minimumDepositAmount() external view returns (uint);
+
+    function synthsReceivedForEther(uint amount) external view returns (uint);
+
+    function totalSellableDeposits() external view returns (uint);
 
+    // Mutative functions
     function depositSynths(uint amount) external;
 
+    function exchangeEtherForSynths() external payable returns (uint);
+
+    function exchangeEtherForSynthsAtRate(uint guaranteedRate) external payable returns (uint);
+
     function withdrawMyDepositedSynths() external;
 
-    // Deprecated ABI for MAINNET. Only used on Testnets
+    // Note: On mainnet no SNX has been deposited. The following functions are kept alive for testnet SNX faucets.
     function exchangeEtherForSNX() external payable returns (uint);
 
     function exchangeEtherForSNXAtRate(uint guaranteedRate, uint guaranteedSynthetixRate) external payable returns (uint);

contracts/interfaces/IExchangeRates.sol

@@ -1,26 +1,22 @@
 pragma solidity ^0.5.16;
 
+import "@chainlink/contracts-0.0.3/src/v0.5/dev/AggregatorInterface.sol";
+
 
 interface IExchangeRates {
     // Views
+    function aggregators(bytes32 currencyKey) external view returns (AggregatorInterface);
+
+    function anyRateIsStale(bytes32[] calldata currencyKeys) external view returns (bool);
+
+    function currentRoundForRate(bytes32 currencyKey) external view returns (uint);
+
     function effectiveValue(
         bytes32 sourceCurrencyKey,
         uint sourceAmount,
         bytes32 destinationCurrencyKey
     ) external view returns (uint);
 
-    function rateForCurrency(bytes32 currencyKey) external view returns (uint);
-
-    function ratesForCurrencies(bytes32[] calldata currencyKeys) external view returns (uint[] memory);
-
-    function rateIsStale(bytes32 currencyKey) external view returns (bool);
-
-    function rateIsFrozen(bytes32 currencyKey) external view returns (bool);
-
-    function anyRateIsStale(bytes32[] calldata currencyKeys) external view returns (bool);
-
-    function getCurrentRoundId(bytes32 currencyKey) external view returns (uint);
-
     function effectiveValueAtRound(
         bytes32 sourceCurrencyKey,
         uint sourceAmount,
@@ -29,14 +25,40 @@ interface IExchangeRates {
         uint roundIdForDest
     ) external view returns (uint);
 
+    function getCurrentRoundId(bytes32 currencyKey) external view returns (uint);
+
     function getLastRoundIdBeforeElapsedSecs(
         bytes32 currencyKey,
         uint startingRoundId,
         uint startingTimestamp,
         uint timediff
     ) external view returns (uint);
 
-    function ratesAndStaleForCurrencies(bytes32[] calldata currencyKeys) external view returns (uint[] memory, bool);
+    function inversePricing(bytes32 currencyKey)
+        external
+        view
+        returns (
+            uint entryPoint,
+            uint upperLimit,
+            uint lowerLimit,
+            bool frozen
+        );
+
+    function lastRateUpdateTimes(bytes32 currencyKey) external view returns (uint256);
+
+    function oracle() external view returns (address);
 
     function rateAndTimestampAtRound(bytes32 currencyKey, uint roundId) external view returns (uint rate, uint time);
+
+    function rateForCurrency(bytes32 currencyKey) external view returns (uint);
+
+    function rateIsFrozen(bytes32 currencyKey) external view returns (bool);
+
+    function rateIsStale(bytes32 currencyKey) external view returns (bool);
+
+    function ratesAndStaleForCurrencies(bytes32[] calldata currencyKeys) external view returns (uint[] memory, bool);
+
+    function ratesForCurrencies(bytes32[] calldata currencyKeys) external view returns (uint[] memory);
+
+    function rateStalePeriod() external view returns (uint);
 }

contracts/interfaces/IExchanger.sol

@@ -3,10 +3,17 @@ pragma solidity ^0.5.16;
 
 interface IExchanger {
     // Views
-    function maxSecsLeftInWaitingPeriod(address account, bytes32 currencyKey) external view returns (uint);
+    function calculateAmountAfterSettlement(
+        address from,
+        bytes32 currencyKey,
+        uint amount,
+        uint refunded
+    ) external view returns (uint amountAfterSettlement);
 
     function feeRateForExchange(bytes32 sourceCurrencyKey, bytes32 destinationCurrencyKey) external view returns (uint);
 
+    function maxSecsLeftInWaitingPeriod(address account, bytes32 currencyKey) external view returns (uint);
+
     function settlementOwing(address account, bytes32 currencyKey)
         external
         view
@@ -16,22 +23,7 @@ interface IExchanger {
             uint numEntries
         );
 
-    function calculateAmountAfterSettlement(
-        address from,
-        bytes32 currencyKey,
-        uint amount,
-        uint refunded
-    ) external view returns (uint amountAfterSettlement);
-
     // Mutative functions
-    function settle(address from, bytes32 currencyKey)
-        external
-        returns (
-            uint reclaimed,
-            uint refunded,
-            uint numEntries
-        );
-
     function exchange(
         address from,
         bytes32 sourceCurrencyKey,
@@ -47,4 +39,12 @@ interface IExchanger {
         uint sourceAmount,
         bytes32 destinationCurrencyKey
     ) external returns (uint amountReceived);
+
+    function settle(address from, bytes32 currencyKey)
+        external
+        returns (
+            uint reclaimed,
+            uint refunded,
+            uint numEntries
+        );
 }

contracts/interfaces/IFeePool.sol

@@ -3,22 +3,36 @@ pragma solidity ^0.5.16;
 
 interface IFeePool {
     // Views
+    function amountReceivedFromExchange(uint value) external view returns (uint);
+
+    function exchangeFeeRate() external view returns (uint);
 
-    // solhint-disable func-name-mixedcase
+    // solhint-disable-next-line func-name-mixedcase
     function FEE_ADDRESS() external view returns (address);
 
-    function exchangeFeeRate() external view returns (uint);
+    function feesAvailable(address account) external view returns (uint, uint);
 
-    function amountReceivedFromExchange(uint value) external view returns (uint);
+    function isFeesClaimable(address account) external view returns (bool);
+
+    function totalFeesAvailable() external view returns (uint);
+
+    function totalRewardsAvailable() external view returns (uint);
 
     // Mutative Functions
-    function recordFeePaid(uint sUSDAmount) external;
+    function claimFees() external returns (bool);
+
+    function claimOnBehalf(address claimingForAddress) external returns (bool);
 
+    function closeCurrentFeePeriod() external;
+
+    // Restricted: used internally to Synthetix
     function appendAccountIssuanceRecord(
         address account,
         uint lockedAmount,
         uint debtEntryIndex
     ) external;
 
+    function recordFeePaid(uint sUSDAmount) external;
+
     function setRewardsToDistribute(uint amount) external;
 }

contracts/interfaces/IIssuer.sol

@@ -7,7 +7,7 @@ interface IIssuer {
 
     function lastIssueEvent(address account) external view returns (uint);
 
-    // Mutative functions
+    // Restricted: used internally to Synthetix
     function issueSynths(address from, uint amount) external;
 
     function issueSynthsOnBehalf(

contracts/interfaces/ISynth.sol

@@ -5,16 +5,19 @@ interface ISynth {
     // Views
     function currencyKey() external view returns (bytes32);
 
-    // Mutative functions
-    function burn(address account, uint amount) external;
-
-    function issue(address account, uint amount) external;
+    function transferableSynths(address account) external view returns (uint);
 
+    // Mutative functions
     function transferAndSettle(address to, uint value) external returns (bool);
 
     function transferFromAndSettle(
         address from,
         address to,
         uint value
     ) external returns (bool);
+
+    // Restricted: used internally to Synthetix
+    function burn(address account, uint amount) external;
+
+    function issue(address account, uint amount) external;
 }

contracts/interfaces/ISynthetix.sol

@@ -5,15 +5,13 @@ import "../interfaces/ISynth.sol";
 
 interface ISynthetix {
     // Views
-    function synths(bytes32 currencyKey) external view returns (ISynth);
+    function availableCurrencyKeys() external view returns (bytes32[] memory);
 
-    function synthsByAddress(address synthAddress) external view returns (bytes32);
+    function availableSynthCount() external view returns (uint);
 
-    function collateralisationRatio(address issuer) external view returns (uint);
-
-    function totalIssuedSynths(bytes32 currencyKey) external view returns (uint);
+    function collateral(address account) external view returns (uint);
 
-    function totalIssuedSynthsExcludeEtherCollateral(bytes32 currencyKey) external view returns (uint);
+    function collateralisationRatio(address issuer) external view returns (uint);
 
     function debtBalanceOf(address issuer, bytes32 currencyKey) external view returns (uint);
 
@@ -22,6 +20,10 @@ interface ISynthetix {
         view
         returns (uint debtBalance, uint totalSystemValue);
 
+    function isWaitingPeriod(bytes32 currencyKey) external view returns (bool);
+
+    function maxIssuableSynths(address issuer) external view returns (uint maxIssuable);
+
     function remainingIssuableSynths(address issuer)
         external
         view
@@ -31,24 +33,47 @@ interface ISynthetix {
             uint totalSystemDebt
         );
 
-    function maxIssuableSynths(address issuer) external view returns (uint maxIssuable);
+    function synths(bytes32 currencyKey) external view returns (ISynth);
 
-    function isWaitingPeriod(bytes32 currencyKey) external view returns (bool);
+    function synthsByAddress(address synthAddress) external view returns (bytes32);
+
+    function totalIssuedSynths(bytes32 currencyKey) external view returns (uint);
+
+    function totalIssuedSynthsExcludeEtherCollateral(bytes32 currencyKey) external view returns (uint);
+
+    function transferableSynthetix(address account) external view returns (uint);
 
     // Mutative Functions
+    function burnSynths(uint amount) external;
+
+    function burnSynthsOnBehalf(address burnForAddress, uint amount) external;
+
+    function burnSynthsToTarget() external;
+
+    function burnSynthsToTargetOnBehalf(address burnForAddress) external;
+
     function exchange(
         bytes32 sourceCurrencyKey,
         uint sourceAmount,
         bytes32 destinationCurrencyKey
     ) external returns (uint amountReceived);
 
-    function issueSynths(uint amount) external;
+    function exchangeOnBehalf(
+        address exchangeForAddress,
+        bytes32 sourceCurrencyKey,
+        uint sourceAmount,
+        bytes32 destinationCurrencyKey
+    ) external returns (uint amountReceived);
 
     function issueMaxSynths() external;
 
-    function burnSynths(uint amount) external;
+    function issueMaxSynthsOnBehalf(address issueForAddress) external;
 
-    function burnSynthsToTarget() external;
+    function issueSynths(uint amount) external;
+
+    function issueSynthsOnBehalf(address issueForAddress, uint amount) external;
+
+    function mint() external returns (bool);
 
     function settle(bytes32 currencyKey)
         external