Merge pull request #39 from 0xPolygon/feat/emission-adjustment

change staking emission from 1 to 2 percent

.gitignore

@@ -4,6 +4,7 @@
 /coverage
 lcov.info
 .DS_Store
+.vscode
 .env
 
 broadcast/*/31337

src/DefaultEmissionManager.sol

@@ -9,15 +9,15 @@ import {SafeERC20} from "openzeppelin-contracts/contracts/token/ERC20/utils/Safe
 import {PowUtil} from "./lib/PowUtil.sol";
 
 /// @title Default Emission Manager
-/// @author Polygon Labs (@DhairyaSethi, @gretzke, @qedk)
+/// @author Polygon Labs (@DhairyaSethi, @gretzke, @qedk, @simonDos)
 /// @notice A default emission manager implementation for the Polygon ERC20 token contract on Ethereum L1
-/// @dev The contract allows for a 1% mint *each* per year (compounded every year) to the stakeManager and treasury contracts
+/// @dev The contract allows for a 3% mint per year (compounded). 2% stakeManager(Hub) and 1% treasury
 /// @custom:security-contact [email protected]
 contract DefaultEmissionManager is Ownable2StepUpgradeable, IDefaultEmissionManager {
     using SafeERC20 for IPolygonEcosystemToken;
 
-    // log2(2%pa continuously compounded emission per year) in 18 decimals, see _inflatedSupplyAfter
-    uint256 public constant INTEREST_PER_YEAR_LOG2 = 0.028569152196770894e18;
+    // log2(3%pa continuously compounded emission per year) in 18 decimals, see _inflatedSupplyAfter
+    uint256 public constant INTEREST_PER_YEAR_LOG2 = 0.04264433740849372e18;
     uint256 public constant START_SUPPLY = 10_000_000_000e18;
     address private immutable DEPLOYER;
 
@@ -65,7 +65,7 @@ contract DefaultEmissionManager is Ownable2StepUpgradeable, IDefaultEmissionMana
         uint256 amountToMint = newSupply - currentSupply;
         if (amountToMint == 0) return; // no minting required
 
-        uint256 treasuryAmt = amountToMint / 2;
+        uint256 treasuryAmt = amountToMint / 3;
         uint256 stakeManagerAmt = amountToMint - treasuryAmt;
 
         emit TokenMint(amountToMint, msg.sender);
@@ -79,10 +79,10 @@ contract DefaultEmissionManager is Ownable2StepUpgradeable, IDefaultEmissionMana
 
     /// @notice Returns total supply from compounded emission after timeElapsed from startTimestamp (deployment)
     /// @param timeElapsed The time elapsed since startTimestamp
-    /// @dev interestRatePerYear = 1.02; 2% per year
+    /// @dev interestRatePerYear = 1.03; 3% per year
     /// approximate the compounded interest rate using x^y = 2^(log2(x)*y)
     /// where x is the interest rate per year and y is the number of seconds elapsed since deployment divided by 365 days in seconds
-    /// log2(interestRatePerYear) = 0.028569152196770894 with 18 decimals, as the interest rate does not change, hard code the value
+    /// log2(interestRatePerYear) = 0.04264433740849372 with 18 decimals, as the interest rate does not change, hard code the value
     /// @return supply total supply from compounded emission after timeElapsed
     function inflatedSupplyAfter(uint256 timeElapsed) public pure returns (uint256 supply) {
         uint256 supplyFactor = PowUtil.exp2((INTEREST_PER_YEAR_LOG2 * timeElapsed) / 365 days);
@@ -92,7 +92,7 @@ contract DefaultEmissionManager is Ownable2StepUpgradeable, IDefaultEmissionMana
     /// @notice Returns the implementation version
     /// @return Version string
     function getVersion() external pure returns (string memory) {
-        return "1.0.0";
+        return "1.1.0";
     }
 
     /**

src/PolygonEcosystemToken.sol

@@ -6,7 +6,7 @@ import {AccessControlEnumerable} from "openzeppelin-contracts/contracts/access/A
 import {IPolygonEcosystemToken} from "./interfaces/IPolygonEcosystemToken.sol";
 
 /// @title Polygon ERC20 token
-/// @author Polygon Labs (@DhairyaSethi, @gretzke, @qedk)
+/// @author Polygon Labs (@DhairyaSethi, @gretzke, @qedk, @simonDos)
 /// @notice This is the Polygon ERC20 token contract on Ethereum L1
 /// @dev The contract allows for a 1-to-1 representation between $POL and $MATIC and allows for additional emission based on hub and treasury requirements
 /// @custom:security-contact [email protected]
@@ -15,7 +15,7 @@ contract PolygonEcosystemToken is ERC20Permit, AccessControlEnumerable, IPolygon
     bytes32 public constant CAP_MANAGER_ROLE = keccak256("CAP_MANAGER_ROLE");
     bytes32 public constant PERMIT2_REVOKER_ROLE = keccak256("PERMIT2_REVOKER_ROLE");
     address public constant PERMIT2 = 0x000000000022D473030F116dDEE9F6B43aC78BA3;
-    uint256 public mintPerSecondCap = 10e18; // 10 POL tokens per second
+    uint256 public mintPerSecondCap = 13.37e18; // 13.37 POL tokens per second. will limit emission in ~23 years
     uint256 public lastMint;
     bool public permit2Enabled;
 
@@ -78,7 +78,7 @@ contract PolygonEcosystemToken is ERC20Permit, AccessControlEnumerable, IPolygon
     /// this contract not being behind a proxy
     /// @return Version string
     function getVersion() external pure returns (string memory) {
-        return "1.0.0";
+        return "1.1.0";
     }
 
     function _updatePermit2Allowance(bool enabled) private {

test/DefaultEmissionManager.t.sol

@@ -143,9 +143,12 @@ contract DefaultEmissionManagerTest is Test {
         uint256 newSupply = abi.decode(vm.ffi(inputs), (uint256));
 
         assertApproxEqAbs(newSupply, polygon.totalSupply(), _MAX_PRECISION_DELTA);
-        assertEq(matic.balanceOf(stakeManager), (polygon.totalSupply() - initialTotalSupply) / 2);
+        uint256 totalAmtMinted = polygon.totalSupply() - initialTotalSupply;
+        uint256 totalAmtMintedOneThird = totalAmtMinted / 3;
+        assertEq(matic.balanceOf(stakeManager), totalAmtMinted - totalAmtMintedOneThird);
+        assertEq(matic.balanceOf(treasury), 0);
         assertEq(polygon.balanceOf(stakeManager), 0);
-        assertEq(polygon.balanceOf(treasury), (polygon.totalSupply() - initialTotalSupply) / 2);
+        assertEq(polygon.balanceOf(treasury), totalAmtMintedOneThird);
     }
 
     function test_MintDelayTwice(uint128 delay) external {
@@ -161,8 +164,9 @@ contract DefaultEmissionManagerTest is Test {
         uint256 newSupply = abi.decode(vm.ffi(inputs), (uint256));
 
         assertApproxEqAbs(newSupply, polygon.totalSupply(), _MAX_PRECISION_DELTA);
-        uint256 balance = (polygon.totalSupply() - initialTotalSupply) / 2;
-        assertEq(matic.balanceOf(stakeManager), balance);
+        uint256 balance = (polygon.totalSupply() - initialTotalSupply) / 3;
+        uint256 stakeManagerBalance = (polygon.totalSupply() - initialTotalSupply) - balance;
+        assertEq(matic.balanceOf(stakeManager), stakeManagerBalance);
         assertEq(polygon.balanceOf(stakeManager), 0);
         assertEq(polygon.balanceOf(treasury), balance);
 
@@ -175,8 +179,13 @@ contract DefaultEmissionManagerTest is Test {
         newSupply = abi.decode(vm.ffi(inputs), (uint256));
 
         assertApproxEqAbs(newSupply, polygon.totalSupply(), _MAX_PRECISION_DELTA);
-        balance += (polygon.totalSupply() - initialTotalSupply) / 2;
-        assertEq(matic.balanceOf(stakeManager), balance);
+        uint256 totalAmtMinted = polygon.totalSupply() - initialTotalSupply;
+        uint256 totalAmtMintedOneThird = totalAmtMinted / 3;
+
+        balance += totalAmtMintedOneThird;
+        stakeManagerBalance += totalAmtMinted - totalAmtMintedOneThird;
+
+        assertEq(matic.balanceOf(stakeManager), stakeManagerBalance);
         assertEq(polygon.balanceOf(stakeManager), 0);
         assertEq(polygon.balanceOf(treasury), balance);
     }
@@ -185,6 +194,7 @@ contract DefaultEmissionManagerTest is Test {
         vm.assume(delay * uint256(cycles) <= 10 * 365 days && delay > 0 && cycles < 30);
 
         uint256 balance;
+        uint256 stakeManagerBalance;
 
         for (uint256 cycle; cycle < cycles; cycle++) {
             uint256 initialTotalSupply = polygon.totalSupply();
@@ -197,8 +207,13 @@ contract DefaultEmissionManagerTest is Test {
             uint256 newSupply = abi.decode(vm.ffi(inputs), (uint256));
 
             assertApproxEqAbs(newSupply, polygon.totalSupply(), _MAX_PRECISION_DELTA);
-            balance += (polygon.totalSupply() - initialTotalSupply) / 2;
-            assertEq(matic.balanceOf(stakeManager), balance);
+            uint256 totalAmtMinted = polygon.totalSupply() - initialTotalSupply;
+            uint256 totalAmtMintedOneThird = totalAmtMinted / 3;
+
+            balance += totalAmtMintedOneThird;
+            stakeManagerBalance += totalAmtMinted - totalAmtMintedOneThird;
+
+            assertEq(matic.balanceOf(stakeManager), stakeManagerBalance);
             assertEq(polygon.balanceOf(stakeManager), 0);
             assertEq(polygon.balanceOf(treasury), balance);
         }
@@ -209,6 +224,6 @@ contract DefaultEmissionManagerTest is Test {
         inputs[2] = vm.toString(delay);
         inputs[3] = vm.toString(polygon.totalSupply());
         uint256 newSupply = abi.decode(vm.ffi(inputs), (uint256));
-        assertApproxEqAbs(newSupply, emissionManager.inflatedSupplyAfter(block.timestamp + delay), 1e19);
+        assertApproxEqAbs(newSupply, emissionManager.inflatedSupplyAfter(block.timestamp + delay), 1e20);
     }
 }

test/PolygonEcosystemToken.t.sol

@@ -18,7 +18,7 @@ contract PolygonTest is Test {
     address public governance;
     address public permit2revoker;
     DefaultEmissionManager public emissionManager;
-    uint256 public mintPerSecondCap = 10e18; // 10 POL tokens per second
+    uint256 public mintPerSecondCap = 13.37e18; // 13.37 POL tokens per second
 
     function setUp() external {
         migration = makeAddr("migration");

test/util/calc.js

@@ -1,4 +1,4 @@
-const interestRatePerYear = 1.02;
+const interestRatePerYear = 1.03;
 const startSupply = 10_000_000_000e18;
 function main() {
     const [timeElapsedInSeconds] = process.argv.slice(2);