bump RWA oracle price + test

src/DssSpell.sol

@@ -20,6 +20,10 @@ import "dss-exec-lib/DssExec.sol";
 import "dss-exec-lib/DssAction.sol";
 import { VatAbstract } from "dss-interfaces/dss/VatAbstract.sol";
 
+interface RwaLiquidationOracleLike {
+    function bump(bytes32 ilk, uint256 val) external;
+}
+
 contract DssSpellAction is DssAction {
     // Provides a descriptive tag for bot consumption
     string public constant override description = "Goerli Spell";
@@ -53,16 +57,21 @@ contract DssSpellAction is DssAction {
 
     // ---------- Math ----------
     uint256 internal constant THOUSAND = 10 ** 3;
+    uint256 internal constant MILLION  = 10 ** 6;
     uint256 internal constant BILLION  = 10 ** 9;
+    uint256 internal constant WAD      = 10 ** 18;
     uint256 internal constant RAD      = 10 ** 45;
 
     // ---------- SBE parameter changes ----------
     address internal immutable MCD_VOW            = DssExecLib.vow();
     address internal immutable MCD_FLAP           = DssExecLib.flap();
 
-    // ---------- Debt Ceiling ----------
+    // ---------- Reduce PSM-GUSD-A Debt Ceiling ----------
     VatAbstract internal immutable vat            = VatAbstract(DssExecLib.vat());
 
+    // ---------- Increase RWA014-A (Coinbase Custody) Debt Ceiling ----------
+    address internal immutable MIP21_LIQUIDATION_ORACLE = DssExecLib.getChangelogAddress("MIP21_LIQUIDATION_ORACLE");
+
     function actions() public override {
         // ---------- Stability Fee Changes ----------
         // Forum: https://forum.makerdao.com/t/stability-scope-parameter-changes-7/22882#increase-rwa014-a-coinbase-custody-debt-ceiling-9
@@ -96,6 +105,17 @@ contract DssSpellAction is DssAction {
         // Increase the RWA014-A (Coinbase Custody) debt ceiling by 1b DAI, from 500M to 1.5b
         DssExecLib.increaseIlkDebtCeiling("RWA014-A", 1 * BILLION, /* global = */ true);
 
+        // Note: we have to bump the oracle price to account for the new DC
+        // Note: the formula is `Debt ceiling * [ (1 + RWA stability fee ) ^ (minimum deal duration in years) ] * liquidation ratio`
+        // Note: as stability fee is 0 for this deal, this should be equal to ilk DC
+        RwaLiquidationOracleLike(MIP21_LIQUIDATION_ORACLE).bump(
+            "RWA014-A",
+            1500 * MILLION * WAD
+        );
+
+        // Note: we have to update collateral price to propagate the changes
+        DssExecLib.updateCollateralPrice("RWA014-A");
+
         // ---------- SBE parameter changes ----------
         // Forum: https://forum.makerdao.com/t/smart-burn-engine-transaction-analysis-parameter-reconfiguration-update-3/22876
 

src/DssSpell.t.sol

@@ -36,12 +36,16 @@ interface BridgeLike {
     function l2TeleportGateway() external view returns (address);
 }
 
+interface SpellActionLike {
+    function dao_resolutions() external view returns (string memory);
+}
+
 interface ProxyLike {
     function exec(address target, bytes calldata args) external payable returns (bytes memory out);
 }
 
-interface SpellActionLike {
-    function dao_resolutions() external view returns (string memory);
+interface RwaLiquidationOracleLike {
+    function ilks(bytes32) external view returns (string memory, address, uint48 toc, uint48 tau);
 }
 
 contract DssSpellTest is DssSpellTestBase {
@@ -545,4 +549,20 @@ contract DssSpellTest is DssSpellTestBase {
     }
 
     // SPELL-SPECIFIC TESTS GO BELOW
+
+    // RWA tests
+    RwaLiquidationOracleLike oracle = RwaLiquidationOracleLike(addr.addr("MIP21_LIQUIDATION_ORACLE"));
+    function testRWApriceBump() public {
+        _vote(address(spell));
+        _scheduleWaitAndCast(address(spell));
+        assertTrue(spell.done());
+
+        // Get the oracle address
+        (,address pip,,  ) = oracle.ilks("RWA014-A");
+        assertEq(uint256(DSValueAbstract(pip).read()), 1_500_000_000 * WAD, "RWA014: Bad pip value after bump()");
+
+        // Get collateral's parameters
+        (,, uint256 spot,,) = vat.ilks("RWA014-A");
+        assertEq(spot, 1_500_000_000 * RAY, "RWA014: Bad spot value after bump()");
+    }
 }