Add test for prank() cheatcode

Author: elopez

src/test/Tests/Cheat.hs

@@ -2,7 +2,7 @@ module Tests.Cheat (cheatTests) where
 
 import Test.Tasty (TestTree, testGroup)
 
-import Common (testContract', solcV, solved)
+import Common (testContract', solcV, solved, passed)
 
 import Echidna.Types.Campaign (WorkerType(..))
 
@@ -15,4 +15,10 @@ cheatTests =
         [ ("echidna_ffi passed", solved "echidna_ffi") ]
     , testContract' "cheat/gas.sol" (Just "TestCheatGas") (Just (> solcV (0,5,0))) (Just "cheat/ffi.yaml") False FuzzWorker
         [ ("echidna_gas_zero passed", solved "echidna_gas_zero") ]
+    , testContract' "cheat/prank.sol" (Just "TestPrank") (Just (> solcV (0,5,0))) (Just "cheat/prank.yaml") False FuzzWorker
+        [ ("withPrank failed",               passed "withPrank")
+        , ("withStartPrank failed",          passed "withStartPrank")
+        , ("withStartPrankStopPrank failed", passed "withStartPrankStopPrank")
+        , ("withNothing failed",             passed "withNothing")
+        ]
     ]

tests/solidity/cheat/prank.sol

@@ -0,0 +1,94 @@
+interface IHevm {
+    function prank(address newSender) external;
+    function startPrank(address sender) external;
+    function stopPrank() external;
+}
+
+contract ExpectedCreator {
+  event Sender(address);
+  event AssertionFailed(string);
+  IHevm constant vm = IHevm(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
+
+  constructor(address s) public {
+    if (s != msg.sender) {
+      emit Sender(msg.sender);
+      emit AssertionFailed("fail on construct");
+    }
+  }
+}
+
+contract SenderVerifierChild {
+  event Sender(address);
+  event AssertionFailed(string);
+  IHevm constant vm = IHevm(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
+
+  function verifyMsgSender(address s) public {
+    if (s != msg.sender) {
+      emit Sender(msg.sender);
+      emit AssertionFailed("fail on inner call");
+    }
+  }
+}
+
+contract SenderVerifierParent {
+  event Sender(address);
+  event AssertionFailed(string);
+  IHevm constant vm = IHevm(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
+
+  SenderVerifierChild c;
+  constructor() public {
+    c = new SenderVerifierChild();
+  }
+
+  function verifyMsgSender(address s) public {
+    if (s != msg.sender) {
+      emit Sender(msg.sender);
+      emit AssertionFailed("fail on first call");
+    }      
+    c.verifyMsgSender(address(this));
+    new ExpectedCreator(address(this));
+  }
+}
+
+contract TestPrank {
+  IHevm constant vm = IHevm(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
+
+  SenderVerifierParent p;
+  constructor() public {
+    p = new SenderVerifierParent();
+  }
+
+  function withPrank() public {
+    vm.prank(address(0x123));
+    p.verifyMsgSender(address(0x123));
+    p.verifyMsgSender(address(this));
+
+    vm.prank(address(0x123));
+    new ExpectedCreator(address(0x123));
+    new ExpectedCreator(address(this));
+  }
+
+  function withStartPrank() public {
+    vm.startPrank(address(0x123));
+    p.verifyMsgSender(address(0x123));
+    p.verifyMsgSender(address(0x123));
+    new ExpectedCreator(address(0x123));
+    new ExpectedCreator(address(0x123));
+  }
+
+  function withStartPrankStopPrank() public {
+    vm.startPrank(address(0x123));
+    p.verifyMsgSender(address(0x123));
+    p.verifyMsgSender(address(0x123));
+    new ExpectedCreator(address(0x123));
+    new ExpectedCreator(address(0x123));
+    vm.stopPrank();
+    p.verifyMsgSender(address(this));
+    new ExpectedCreator(address(this));
+  }
+
+  function withNothing() public {
+    p.verifyMsgSender(address(this));
+    new ExpectedCreator(address(this));
+  }
+}

tests/solidity/cheat/prank.yaml

@@ -0,0 +1,3 @@
+testLimit: 1000
+seqLen: 10
+testMode: assertion