[FIX] compiler: allow t-if with empty content

src/compiler/parser.ts

@@ -639,10 +639,7 @@ function parseTIf(node: Element, ctx: ParsingContext): AST | null {
   }
   const condition = node.getAttribute("t-if")!;
   node.removeAttribute("t-if");
-  const content = parseNode(node, ctx);
-  if (!content) {
-    throw new Error("hmmm");
-  }
+  const content = parseNode(node, ctx) || { type: ASTType.Text, value: "" };
 
   let nextElement = node.nextElementSibling;
   // t-elifs

tests/compiler/__snapshots__/t_if.test.ts.snap

@@ -384,6 +384,23 @@ exports[`t-if t-if in a t-if 1`] = `
 }"
 `;
 
+exports[`t-if t-if with empty content 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { withDefault, getTemplate, prepareList, withKey, zero, call, callSlot, capture, isBoundary, shallowEqual, setContextValue, toNumber, safeOutput } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2,b3;
+    b2 = text(\`hello\`);
+    if (ctx['condition']) {
+      b3 = text(\`\`);
+    }
+    return multi([b2, b3]);
+  }
+}"
+`;
+
 exports[`t-if t-if/t-else with more content 1`] = `
 "function anonymous(bdom, helpers
 ) {

tests/compiler/parser.test.ts

@@ -395,6 +395,19 @@ describe("qweb parser", () => {
     });
   });
 
+  test("t-if with empty content", async () => {
+    expect(parse(`<t t-if="condition"></t>`)).toEqual({
+      type: ASTType.TIf,
+      condition: "condition",
+      content: {
+        type: ASTType.Text,
+        value: "",
+      },
+      tElif: null,
+      tElse: null,
+    });
+  });
+
   test("t-if (on dom node", async () => {
     expect(parse(`<div t-if="condition">hey</div>`)).toEqual({
       type: ASTType.TIf,

tests/compiler/t_if.test.ts

@@ -16,6 +16,12 @@ describe("t-if", () => {
     expect(renderToString(template, {})).toBe("<div></div>");
   });
 
+  test("t-if with empty content", () => {
+    const template = `hello<t t-if="condition"/>`;
+    expect(renderToString(template, { condition: true })).toBe("hello");
+    expect(renderToString(template, { condition: false })).toBe("hello");
+  });
+
   test("boolean value condition missing", () => {
     const template = `<span><t t-if="condition">fail</t></span>`;
     expect(renderToString(template)).toBe("<span></span>");