[IMP] component: support dynamic t-props

It is useful in some rare situations.

closes #144

tests/component/__snapshots__/component.test.ts.snap

@@ -657,6 +657,49 @@ exports[`composition t-component with dynamic value 2 1`] = `
 }"
 `;
 
+exports[`dynamic t-props basic use 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.constructor.utils;
+    let QWeb = this.constructor;
+    let parent = context;
+    let owner = context;
+    let result;
+    var h = this.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('div', p1, c1);
+    result = vn1;
+    //COMPONENT
+    let def3;
+    let w4 = 4 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[4]] : false;
+    let _2_index = c1.length;
+    c1.push(null);
+    let props4 = Object.assign({}, context['some'].obj);
+    if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
+        if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
+            def3 = w4.__owl__.renderPromise;
+        } else {
+            w4.destroy();
+            w4 = false;
+        }
+    }
+    if (!w4) {
+        let componentKey4 = \`Child\`;
+        let W4 = context.constructor.components[componentKey4] || QWeb.components[componentKey4];
+        if (!W4) {throw new Error('Cannot find the definition of component \\"' + componentKey4 + '\\"')}
+        w4 = new W4(parent, props4);
+        parent.__owl__.cmap[4] = w4.__owl__.id;
+        def3 = w4.__prepare();
+        def3 = def3.then(vnode=>{if (w4.__owl__.isDestroyed){return}let pvnode=h(vnode.sel, {key: 4, hook: {insert(vn) {let nvn=w4.__mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;},remove() {},destroy(vn) {w4.destroy();}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
+    } else {
+        def3 = def3 || w4.__updateProps(props4, extra.forceUpdate, extra.patchQueue);
+        def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
+    }
+    extra.promises.push(def3);
+    return result;
+}"
+`;
+
 exports[`lifecycle hooks willPatch/patched hook with t-keepalive 1`] = `
 "function anonymous(context,extra
 ) {

tests/component/component.test.ts

@@ -63,7 +63,6 @@ class WidgetA extends Widget {
   static components = { b: WidgetB };
 }
 
-
 //------------------------------------------------------------------------------
 // Tests
 //------------------------------------------------------------------------------
@@ -900,7 +899,6 @@ describe("destroy method", () => {
       }
     }
 
-
     const parent = new Parent(env);
     await parent.mount(fixture);
     expect(fixture.innerHTML).toBe("<div><span><button>click</button></span></div>");
@@ -2243,7 +2241,6 @@ describe("random stuff/miscellaneous", () => {
       name = "A";
     }
 
-
     const a = new A(env);
     await a.mount(fixture);
     expect(fixture.innerHTML).toBe(`<div>A<div>B</div><div>C<div>D</div><div>E</div></div></div>`);
@@ -4317,7 +4314,7 @@ describe("dynamic root nodes", () => {
         </templates>
     `);
     class TestWidget extends Widget {
-        state = {flag: true};
+      state = { flag: true };
     }
 
     const widget = new TestWidget(env);
@@ -4344,8 +4341,8 @@ describe("dynamic root nodes", () => {
     class ChildA extends Widget {}
     class ChildB extends Widget {}
     class TestWidget extends Widget {
-        static components = {ChildA, ChildB};
-        state = {flag: true};
+      static components = { ChildA, ChildB };
+      state = { flag: true };
     }
 
     const widget = new TestWidget(env);
@@ -4357,5 +4354,38 @@ describe("dynamic root nodes", () => {
 
     expect(fixture.innerHTML).toBe("<div>abc</div>");
   });
+});
 
-});
+describe("dynamic t-props", () => {
+  test("basic use", async () => {
+    expect.assertions(4);
+    env.qweb.addTemplates(`
+        <templates>
+            <span t-name="Child">
+                <t t-esc="props.a + props.b"/>
+            </span>
+            <div t-name="Parent">
+                <Child t-props="some.obj"/>
+            </div>
+        </templates>
+    `);
+    class Child extends Widget {
+      constructor(parent, props) {
+        super(parent, props);
+        expect(props).toEqual({ a: 1, b: 2 });
+        expect(props).not.toBe(widget.some.obj);
+      }
+    }
+    class Parent extends Widget {
+      static components = { Child };
+
+      some = { obj: { a: 1, b: 2 } };
+    }
+
+    const widget = new Parent(env);
+    await widget.mount(fixture);
+
+    expect(fixture.innerHTML).toBe("<div><span>3</span></div>");
+    expect(env.qweb.templates.Parent.fn.toString()).toMatchSnapshot();
+  });
+});

tests/store/connected_component.test.ts

@@ -573,7 +573,6 @@ describe("connecting a component to store", () => {
       }
     }
 
-
     const state = { current: "a", msg: { a: "a", b: "b" } };
     const actions = {
       setCurrent({ state }, c) {
@@ -627,7 +626,6 @@ describe("connecting a component to store", () => {
       }
     }
 
-
     const state = { someId: 1, flag: true, messages: { 1: "abc" } };
     const actions = {
       setFlagToFalse({ state }) {
@@ -714,7 +712,6 @@ describe("connecting a component to store", () => {
       }
     }
 
-
     (<any>env).store = store;
     const app = new TodoApp(env);