[FIX] qweb: handle variable expressions in t-if

closes #390
closes #362

doc/qweb.md

@@ -461,16 +461,16 @@ the context of the `t-foreach`, the value is copied at the end of the foreach
 into the global context.
 
 ```xml
-<t t-set="existing_variable" t-value="False"/>
+<t t-set="existing_variable" t-value="false"/>
 <!-- existing_variable now False -->
 
 <p t-foreach="Array(3)" t-as="i">
-    <t t-set="existing_variable" t-value="True"/>
-    <t t-set="new_variable" t-value="True"/>
-    <!-- existing_variable and new_variable now True -->
+    <t t-set="existing_variable" t-value="true"/>
+    <t t-set="new_variable" t-value="true"/>
+    <!-- existing_variable and new_variable now true -->
 </p>
 
-<!-- existing_variable always True -->
+<!-- existing_variable always true -->
 <!-- new_variable undefined -->
 ```
 

src/qweb/base_directives.ts

@@ -133,7 +133,7 @@ QWeb.addDirective({
   priority: 20,
   atNodeEncounter({ node, ctx }): boolean {
     let cond = ctx.getValue(node.getAttribute("t-if")!);
-    ctx.addIf(`${ctx.formatExpression(cond)}`);
+    ctx.addIf(`${ctx.formatExpression(typeof cond === 'string' ? cond : cond.expr)}`);
     return false;
   },
   finalize({ ctx }) {
@@ -146,7 +146,7 @@ QWeb.addDirective({
   priority: 30,
   atNodeEncounter({ node, ctx }): boolean {
     let cond = ctx.getValue(node.getAttribute("t-elif")!);
-    ctx.addLine(`else if (${ctx.formatExpression(cond)}) {`);
+    ctx.addLine(`else if (${ctx.formatExpression(typeof cond === 'string' ? cond : cond.expr)}) {`);
     ctx.indent();
     return false;
   },

src/qweb/compilation_context.ts

@@ -1,4 +1,4 @@
-import { compileExpr, QWebVar } from "./expression_parser";
+import { compileExpr, QWebVar, QWebExprVar } from "./expression_parser";
 
 export const INTERP_REGEXP = /\{\{.*?\}\}/g;
 //------------------------------------------------------------------------------
@@ -145,7 +145,7 @@ export class CompilationContext {
     this.addLine("}");
   }
 
-  getValue(val: any): any {
+  getValue(val: any): QWebExprVar | string {
     return val in this.variables ? this.getValue(this.variables[val]) : val;
   }
 

src/qweb/qweb.ts

@@ -645,7 +645,7 @@ export class QWeb extends EventBus {
       if (name.startsWith("t-att-")) {
         let attName = name.slice(6);
         const v = ctx.getValue(value);
-        let formattedValue = v.id || ctx.formatExpression(v);
+        let formattedValue = typeof v === 'string' ? ctx.formatExpression(v) : v.id;
 
         if (attName === "class") {
           ctx.rootContext.shouldDefineUtils = true;

tests/qweb/__snapshots__/qweb.test.ts.snap

@@ -1502,6 +1502,22 @@ exports[`t-if t-esc with t-if 1`] = `
 }"
 `;
 
+exports[`t-if t-set, then t-if 1`] = `
+"function anonymous(context,extra
+) {
+    var h = this.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('div', p1, c1);
+    var _2 = 'test';
+    if ('test') {
+        if (_2 || _2 === 0) {
+            c1.push({text: _2});
+        }
+    }
+    return vn1;
+}"
+`;
+
 exports[`t-key can use t-key directive on a node 1`] = `
 "function anonymous(context,extra
 ) {

tests/qweb/qweb.test.ts

@@ -338,6 +338,17 @@ describe("t-if", () => {
     qweb.addTemplate("test", `<div><t t-if="false">abc</t><t t-else="1" t-esc="'x'"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>x</div>");
   });
+
+  test("t-set, then t-if", () => {
+    qweb.addTemplate("test", `
+      <div>
+        <t t-set="title" t-value="'test'"/>
+        <t t-if="title"><t t-esc="title"/></t>
+      </div>`);
+    const result = renderToString(qweb, "test");
+    const expected = `<div>test</div>`;
+    expect(result).toBe(expected);
+  });
 });
 
 describe("attributes", () => {