test that invalid constructor forms throw

models/game.test.js

@@ -23,6 +23,12 @@ export default function() {
       );
     });
 
+    QUnit.test("invalid constructor", function(assert) {
+      assert.throws(
+        function() {new Game("nope", "absolutely", "not"); },
+        new TypeError("unknown form of Game constructor"));
+    });
+
     QUnit.test("low goal", function(assert) {
       assert.throws(
         function() { new Game(0); },

models/round.test.js

@@ -13,6 +13,12 @@ export default function() {
       assert.true(round.canRaise(Team.They), "they initially can raise");
     });
 
+    QUnit.test("invalid constructor", function(assert) {
+      assert.throws(
+        function() {new Round("nope", "absolutely", "not"); },
+        new TypeError("unknown form of Round constructor"));
+    });
+
     QUnit.test("immediate victory", function(assert) {
       let round = new Round();
       round.winner = Team.We;

models/round_result.test.js

@@ -11,6 +11,12 @@ export default function() {
       assert.strictEqual(rr.winner, Team.We, "correct winner");
     });
 
+    QUnit.test("invalid constructor", function(assert) {
+      assert.throws(
+        function() {new RoundResult("nope", "absolutely", "not"); },
+        new TypeError("unknown form of RoundResult constructor"));
+    });
+
     QUnit.test("toStruct", function(assert) {
       let rr = new RoundResult(2, Team.They);
       let struct = rr.toStruct();

models/session.test.js

@@ -19,6 +19,12 @@ export default function() {
       assert.strictEqual(session.theirTeam, "", "their team name");
     });
 
+    QUnit.test("invalid constructor", function(assert) {
+      assert.throws(
+        function() {new Session("nope", "absolutely", "not"); },
+        new TypeError("unknown form of Session constructor"));
+    });
+
     QUnit.test("set goal", function(assert) {
       let session = new Session();
       assert.strictEqual(session.goal, 11, "initial goal");