[IMP] qweb: make t-key directive dynamic

instead of having t-key and t-att-key.

closes #36

tests/qweb.test.ts

@@ -1056,3 +1056,29 @@ describe("whitespace handling", () => {
     expect(result3).toBe(pretagwithonlywhitespace);
   });
 });
+
+describe("t-key", () => {
+  test("can use t-key directive on a node", () => {
+    qweb.addTemplate(
+      "test",
+      `<div t-key="beer.id"><t t-esc="beer.name"/></div>`
+    );
+    expect(
+      renderToString(qweb, "test", { beer: { id: 12, name: "Chimay Rouge" } })
+    ).toBe("<div>Chimay Rouge</div>");
+  });
+
+  test("t-key directive in a list", () => {
+    qweb.addTemplate(
+      "test",
+      `<ul>
+        <li t-foreach="beers" t-as="beer" t-key="beer.id"><t t-esc="beer.name"/></li>
+       </ul>`
+    );
+    expect(
+      renderToString(qweb, "test", {
+        beers: [{ id: 12, name: "Chimay Rouge" }]
+      })
+    ).toMatchSnapshot();
+  });
+});