fix: if t-props is not defined, should fallback on {}

src/qweb.ts

@@ -931,7 +931,7 @@ const widgetDirective: Directive = {
     ctx.addLine(
       `let w${widgetID} = ${templateID} in context.__widget__.cmap ? context.__widget__.children[context.__widget__.cmap[${templateID}]] : false;`
     );
-    ctx.addLine(`let props${widgetID} = ${props};`);
+    ctx.addLine(`let props${widgetID} = ${props || "{}"};`);
     ctx.addLine(`let isNew${widgetID} = !w${widgetID};`);
 
     // check if we can reuse current rendering promise

tests/__snapshots__/component.test.ts.snap

@@ -107,3 +107,49 @@ exports[`random stuff/miscellaneous snapshotting compiled code 1`] = `
     return vn1;
 }"
 `;
+
+exports[`random stuff/miscellaneous t-props should not be undefined (snapshotting) 1`] = `
+"function anonymous(context,extra
+) {
+    let owner = context;
+    let h = this.utils.h;
+    let c1 = [], p1 = {key:1};
+    let vn1 = h('div', p1, c1);
+    //WIDGET
+    let _2_index = c1.length;
+    c1.push(null);
+    let def3;
+    let w4 = 4 in context.__widget__.cmap ? context.__widget__.children[context.__widget__.cmap[4]] : false;
+    let props4 = null;
+    let isNew4 = !w4;
+    if (w4 && w4.__widget__.renderPromise) {
+        if (w4.__widget__.isStarted) {
+            def3 = w4.updateProps(props4, extra.forceUpdate);
+        } else {
+            isNew4 = true
+            if (props4 === w4.__widget__.renderProps) {
+                def3 = w4.__widget__.renderPromise;
+            } else {
+                w4.destroy();
+                w4 = false
+            }
+        }
+    }
+    if (!def3) {
+        if (w4) {
+            def3 = w4.updateProps(props4, extra.forceUpdate);
+        } else {
+            w4 = new context.widgets['child'](owner, props4);
+            context.__widget__.cmap[4] = w4.__widget__.id;
+            def3 = w4._start();
+        }
+    }
+    if (isNew4) {
+        def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4});c1[_2_index]=pvnode;pvnode.data.hook = {insert(vn){let nvn=w4._mount(vnode, vn.elm);pvnode.elm=nvn.elm},remove(){w4.destroy()}}; w4.__widget__.pvnode = pvnode;});
+    } else {
+        def3 = def3.then(()=>{if (w4.__widget__.isDestroyed) {return};let vnode;if (!w4.__widget__.vnode){vnode=w4.__widget__.pvnode} else { vnode=h(w4.__widget__.vnode.sel, {key: 4});vnode.elm=w4.el;vnode.data.hook = {insert(a){a.elm.parentNode.replaceChild(w4.el,a.elm);a.elm=w4.el;w4.__mount();},remove(){w4.destroy()}}}c1[_2_index]=vnode;});
+    }
+    extra.promises.push(def3);
+    return vn1;
+}"
+`;

tests/component.test.ts

@@ -939,6 +939,22 @@ describe("random stuff/miscellaneous", () => {
     await widget.mount(fixture);
     expect(env.qweb.templates.parent.toString()).toMatchSnapshot();
   });
+
+  test("t-props should not be undefined (snapshotting)", async () => {
+    env.qweb.addTemplate("parent", `<div><t t-widget="child"/></div>`);
+    class Parent extends Widget {
+      inlineTemplate = "parent";
+      widgets = { child: Child };
+    }
+
+    class Child extends Widget {
+      inlineTemplate = `<span>abc</span>`;
+    }
+
+    const widget = new Parent(env);
+    await widget.mount(fixture);
+    expect(env.qweb.templates.parent.toString()).toMatchSnapshot();
+  });
 });
 
 describe("async rendering", () => {