feat(forge): change startPrank to overwrite existing prank instead of erroring

evm/src/executor/inspector/cheatcodes/env.rs

@@ -120,10 +120,6 @@ fn prank(
 ) -> Result<Bytes, Bytes> {
     let prank = Prank { prank_caller, prank_origin, new_caller, new_origin, depth, single_call };
 
-    if state.prank.is_some() {
-        return Err("You have an active prank already.".encode().into())
-    }
-
     if state.broadcast.is_some() {
         return Err("You cannot `prank` for a broadcasted transaction. Pass the desired tx.origin into the broadcast cheatcode call".encode().into());
     }

testdata/cheats/Prank.t.sol

@@ -118,6 +118,58 @@ contract PrankTest is DSTest {
         );
     }
 
+    function testPrank1AfterPrank0(address sender, address origin) public {
+        // Perform the prank
+        address oldOrigin = tx.origin;
+        Victim victim = new Victim();
+        cheats.prank(sender);
+        victim.assertCallerAndOrigin(
+            sender, "msg.sender was not set during prank", oldOrigin, "tx.origin was not set during prank"
+        );
+
+        // Ensure we cleaned up correctly
+        victim.assertCallerAndOrigin(
+            address(this), "msg.sender was not cleaned up", oldOrigin, "tx.origin invariant failed"
+        );
+
+        // Overwrite the prank
+        cheats.prank(sender, origin);
+        victim.assertCallerAndOrigin(
+            sender, "msg.sender was not set during prank", origin, "tx.origin invariant failed"
+        );
+
+        // Ensure we cleaned up correctly
+        victim.assertCallerAndOrigin(
+            address(this), "msg.sender was not cleaned up", oldOrigin, "tx.origin invariant failed"
+        );
+    }
+
+    function testPrank0AfterPrank1(address sender, address origin) public {
+        // Perform the prank
+        address oldOrigin = tx.origin;
+        Victim victim = new Victim();
+        cheats.prank(sender, origin);
+        victim.assertCallerAndOrigin(
+            sender, "msg.sender was not set during prank", origin, "tx.origin was not set during prank"
+        );
+
+        // Ensure we cleaned up correctly
+        victim.assertCallerAndOrigin(
+            address(this), "msg.sender was not cleaned up", oldOrigin, "tx.origin invariant failed"
+        );
+
+        // Overwrite the prank
+        cheats.prank(sender);
+        victim.assertCallerAndOrigin(
+            sender, "msg.sender was not set during prank", oldOrigin, "tx.origin invariant failed"
+        );
+
+        // Ensure we cleaned up correctly
+        victim.assertCallerAndOrigin(
+            address(this), "msg.sender was not cleaned up", oldOrigin, "tx.origin invariant failed"
+        );
+    }
+
     function testPrankConstructorSender(address sender) public {
         cheats.prank(sender);
         ConstructorVictim victim = new ConstructorVictim(