added version to tinlake (#71)

src/reception.sol

@@ -45,18 +45,24 @@ contract Reception is TitleOwned {
     modifier auth { require(wards[msg.sender] == 1); _; }
 
     // --- Data ---
-
     DeskLike desk;
     ShelfLike shelf;
     PileLike pile;
 
+    bytes32 public version;
+
     constructor (address desk_, address title_, address shelf_, address pile_) TitleOwned(title_) public {
         wards[msg.sender] = 1;
         desk = DeskLike(desk_);
         shelf = ShelfLike(shelf_);
         pile = PileLike(pile_);
     }
 
+    function file(bytes32 what, bytes32 data) public auth {
+        if (what == "version") version = data;
+        else revert();
+    }
+
     // --- Reception ---
     function borrow(uint loan, address deposit) public owner(loan) {
         shelf.deposit(loan, msg.sender);

src/test/reception.t.sol

@@ -123,6 +123,18 @@ contract ReceptionTest is DSTest {
         repay(loan, principal);
     }
 
+    function testFileVersion() public {
+        bytes32 version = keccak256("1");
+        reception.file("version",version);
+        assertEq(version, reception.version());
+    }
+
+    function testFailFileVersion() public {
+        bytes32 version = keccak256("1");
+        reception.file("wrong",version);
+        assertEq(version, reception.version());
+    }
+
     function testClose() public {
         uint loan = 1;
         uint principal = 500;