diff --git a/src/app/template_helpers.ts b/src/app/template_helpers.ts
index a58fea19..845cd001 100644
--- a/src/app/template_helpers.ts
+++ b/src/app/template_helpers.ts
@@ -101,6 +101,25 @@ function shallowEqual(l1: any[], l2: any[]): boolean {
   return true;
 }
 
+class LazyValue {
+  fn: any;
+  ctx: any;
+  node: any;
+  constructor(fn: any, ctx: any, node: any) {
+    this.fn = fn;
+    this.ctx = capture(ctx);
+    this.node = node;
+  }
+
+  evaluate(): any {
+    return this.fn(this.ctx, this.node);
+  }
+
+  toString() {
+    return this.evaluate().toString();
+  }
+}
+
 /*
  * Safely outputs `value` as a block depending on the nature of `value`
  */
@@ -113,6 +132,9 @@ export function safeOutput(value: any): ReturnType<typeof toggler> {
   if (value instanceof Markup) {
     safeKey = `string_safe`;
     block = html(value as string);
+  } else if (value instanceof LazyValue) {
+    safeKey = `lazy_value`;
+    block = value.evaluate();
   } else if (typeof value === "string") {
     safeKey = "string_unsafe";
     block = text(value);
@@ -172,6 +194,7 @@ export const UTILS = {
   shallowEqual,
   toNumber,
   validateProps,
+  LazyValue,
   safeOutput,
   bind,
 };
diff --git a/src/compiler/code_generator.ts b/src/compiler/code_generator.ts
index dec4c8d1..1494c9f4 100644
--- a/src/compiler/code_generator.ts
+++ b/src/compiler/code_generator.ts
@@ -966,10 +966,17 @@ export class CodeGenerator {
     this.helpers.add("isBoundary").add("withDefault");
     const expr = ast.value ? compileExpr(ast.value || "") : "null";
     if (ast.body) {
+      const initialTarget = this.target;
+      this.helpers.add("LazyValue");
+      let name = this.generateId("value");
+      const fn = new CodeTarget(name);
+      this.targets.push(fn);
+      this.target = fn;
       const subCtx: Context = createContext(ctx);
-      const nextId = `b${BlockDescription.nextBlockId}`;
       this.compileAST({ type: ASTType.Multi, content: ast.body }, subCtx);
-      const value = ast.value ? (nextId ? `withDefault(${expr}, ${nextId})` : expr) : nextId;
+      this.target = initialTarget;
+      let value = `new LazyValue(${name}, ctx, node)`;
+      value = ast.value ? (value ? `withDefault(${expr}, ${value})` : expr) : value;
       this.addLine(`ctx[\`${ast.name}\`] = ${value};`);
     } else {
       let value: string;
diff --git a/tests/compiler/__snapshots__/t_esc.test.ts.snap b/tests/compiler/__snapshots__/t_esc.test.ts.snap
index c2489667..844c33c5 100644
--- a/tests/compiler/__snapshots__/t_esc.test.ts.snap
+++ b/tests/compiler/__snapshots__/t_esc.test.ts.snap
@@ -114,16 +114,19 @@ exports[`t-esc t-esc is escaped 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault } = helpers;
+  let { isBoundary, withDefault, LazyValue } = helpers;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   let block2 = createBlock(\`<p>escaped</p>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b2 = block2();
-    ctx[\`var\`] = b2;
+    ctx[\`var\`] = new LazyValue(value1, ctx, node);
     let txt1 = ctx['var'];
     return block1([txt1]);
   }
diff --git a/tests/compiler/__snapshots__/t_out.test.ts.snap b/tests/compiler/__snapshots__/t_out.test.ts.snap
index 69190bb8..cf76a615 100644
--- a/tests/compiler/__snapshots__/t_out.test.ts.snap
+++ b/tests/compiler/__snapshots__/t_out.test.ts.snap
@@ -134,16 +134,19 @@ exports[`t-out t-out bdom 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault, safeOutput } = helpers;
+  let { isBoundary, withDefault, LazyValue, safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><span><block-child-0/></span></div>\`);
   let block2 = createBlock(\`<ol>set</ol>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b2 = block2();
-    ctx[\`var\`] = b2;
+    ctx[\`var\`] = new LazyValue(value1, ctx, node);
     let b3 = safeOutput(ctx['var']);
     return block1([], [b3]);
   }
@@ -277,19 +280,22 @@ exports[`t-out t-out switch markup on bdom 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault, safeOutput } = helpers;
+  let { isBoundary, withDefault, LazyValue, safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   let block2 = createBlock(\`<ol>set</ol>\`);
   let block3 = createBlock(\`<span><block-child-0/></span>\`);
   let block5 = createBlock(\`<span><block-child-0/></span>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
     let b3,b5;
-    let b2 = block2();
-    ctx[\`bdom\`] = b2;
+    ctx[\`bdom\`] = new LazyValue(value1, ctx, node);
     if (ctx['hasBdom']) {
       let b4 = safeOutput(ctx['bdom']);
       b3 = block3([], [b4]);
diff --git a/tests/compiler/__snapshots__/t_set.test.ts.snap b/tests/compiler/__snapshots__/t_set.test.ts.snap
index 578371df..525bee84 100644
--- a/tests/compiler/__snapshots__/t_set.test.ts.snap
+++ b/tests/compiler/__snapshots__/t_set.test.ts.snap
@@ -106,15 +106,18 @@ exports[`t-set set from body lookup 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault } = helpers;
+  let { isBoundary, withDefault, LazyValue } = helpers;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return text(ctx['value']);
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b2 = text(ctx['value']);
-    ctx[\`stuff\`] = b2;
+    ctx[\`stuff\`] = new LazyValue(value1, ctx, node);
     let txt1 = ctx['stuff'];
     return block1([txt1]);
   }
@@ -164,18 +167,21 @@ exports[`t-set t-set body is evaluated immediately 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault, setContextValue, safeOutput } = helpers;
+  let { isBoundary, withDefault, setContextValue, LazyValue, safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   let block2 = createBlock(\`<span><block-text-0/></span>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    let txt1 = ctx['v1'];
+    return block2([txt1]);
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
     setContextValue(ctx, \\"v1\\", 'before');
-    let txt1 = ctx['v1'];
-    let b2 = block2([txt1]);
-    ctx[\`v2\`] = b2;
+    ctx[\`v2\`] = new LazyValue(value1, ctx, node);
     setContextValue(ctx, \\"v1\\", 'after');
     let b3 = safeOutput(ctx['v2']);
     return block1([], [b3]);
@@ -427,17 +433,20 @@ exports[`t-set t-set with content and sub t-esc 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault } = helpers;
+  let { isBoundary, withDefault, LazyValue } = helpers;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    let b3 = text(ctx['beep']);
+    let b4 = text(\` boop\`);
+    return multi([b3, b4]);
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b3 = text(ctx['beep']);
-    let b4 = text(\` boop\`);
-    let b2 = multi([b3, b4]);
-    ctx[\`setvar\`] = b2;
+    ctx[\`setvar\`] = new LazyValue(value1, ctx, node);
     let txt1 = ctx['setvar'];
     return block1([txt1]);
   }
@@ -448,19 +457,22 @@ exports[`t-set t-set with t-value (falsy) and body 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault, setContextValue, safeOutput } = helpers;
+  let { isBoundary, withDefault, setContextValue, LazyValue, safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   let block2 = createBlock(\`<span><block-text-0/></span>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    let txt1 = ctx['v1'];
+    return block2([txt1]);
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
     setContextValue(ctx, \\"v3\\", false);
     setContextValue(ctx, \\"v1\\", 'before');
-    let txt1 = ctx['v1'];
-    let b2 = block2([txt1]);
-    ctx[\`v2\`] = withDefault(ctx['v3'], b2);
+    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, node));
     setContextValue(ctx, \\"v1\\", 'after');
     setContextValue(ctx, \\"v3\\", true);
     let b3 = safeOutput(ctx['v2']);
@@ -473,19 +485,22 @@ exports[`t-set t-set with t-value (truthy) and body 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault, setContextValue, safeOutput } = helpers;
+  let { isBoundary, withDefault, setContextValue, LazyValue, safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   let block2 = createBlock(\`<span><block-text-0/></span>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    let txt1 = ctx['v1'];
+    return block2([txt1]);
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
     setContextValue(ctx, \\"v3\\", 'Truthy');
     setContextValue(ctx, \\"v1\\", 'before');
-    let txt1 = ctx['v1'];
-    let b2 = block2([txt1]);
-    ctx[\`v2\`] = withDefault(ctx['v3'], b2);
+    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, node));
     setContextValue(ctx, \\"v1\\", 'after');
     setContextValue(ctx, \\"v3\\", false);
     let b3 = safeOutput(ctx['v2']);
@@ -563,16 +578,19 @@ exports[`t-set value priority (with non text body 1`] = `
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault } = helpers;
+  let { isBoundary, withDefault, LazyValue } = helpers;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   let block2 = createBlock(\`<span>2</span>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b2 = block2();
-    ctx[\`value\`] = withDefault(1, b2);
+    ctx[\`value\`] = withDefault(1, new LazyValue(value1, ctx, node));
     let txt1 = ctx['value'];
     return block1([txt1]);
   }
diff --git a/tests/components/__snapshots__/props.test.ts.snap b/tests/components/__snapshots__/props.test.ts.snap
index 19385916..57fe3991 100644
--- a/tests/components/__snapshots__/props.test.ts.snap
+++ b/tests/components/__snapshots__/props.test.ts.snap
@@ -145,16 +145,19 @@ exports[`basics t-set with a body expression can be passed in props, and then t-
 "function anonymous(bdom, helpers
 ) {
   let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { isBoundary, withDefault } = helpers;
+  let { isBoundary, withDefault, LazyValue } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   let block2 = createBlock(\`<p>43</p>\`);
   
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
     ctx[isBoundary] = 1
-    let b2 = block2();
-    ctx[\`abc\`] = b2;
+    ctx[\`abc\`] = new LazyValue(value1, ctx, node);
     let b3 = component(\`Child\`, {val: ctx['abc']}, key + \`__1\`, node, ctx);
     return block1([], [b3]);
   }
diff --git a/tests/components/__snapshots__/t_set.test.ts.snap b/tests/components/__snapshots__/t_set.test.ts.snap
index 856f76f8..7e9c7128 100644
--- a/tests/components/__snapshots__/t_set.test.ts.snap
+++ b/tests/components/__snapshots__/t_set.test.ts.snap
@@ -47,6 +47,150 @@ exports[`t-set slot setted value (with t-set) not accessible with t-esc 2`] = `
 }"
 `;
 
+exports[`t-set slots with a t-set with a component in body 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { capture, isBoundary, withDefault, LazyValue, safeOutput } = helpers;
+  
+  function slot1(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx[\`v\`] = new LazyValue(value1, ctx, node);
+    let b3 = text(\` in slot \`);
+    let b4 = safeOutput(ctx['v']);
+    return multi([b3, b4]);
+  }
+  
+  function value1(ctx, node, key = \\"\\") {
+    return component(\`C\`, {}, key + \`__1\`, node, ctx);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return component(\`Child\`, {slots: {'default': {__render: slot1, __ctx: ctx1}}}, key + \`__2\`, node, ctx);
+  }
+}"
+`;
+
+exports[`t-set slots with a t-set with a component in body 2`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2 = text(\`Child \`);
+    let b3 = callSlot(ctx, node, key, 'default', false, {});
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`t-set slots with a t-set with a component in body 3`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`C\`);
+  }
+}"
+`;
+
+exports[`t-set slots with an t-set with a component in body 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { capture, isBoundary, withDefault, LazyValue, safeOutput } = helpers;
+  
+  let block4 = createBlock(\`<div>coffee</div>\`);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx[\`v\`] = new LazyValue(value1, ctx, node);
+    let b5 = text(\` tea \`);
+    let b6 = safeOutput(ctx['v']);
+    return multi([b5, b6]);
+  }
+  
+  function value1(ctx, node, key = \\"\\") {
+    let b3 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+    let b4 = block4();
+    return multi([b3, b4]);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return component(\`Blorg\`, {slots: {'default': {__render: slot1, __ctx: ctx1}}}, key + \`__2\`, node, ctx);
+  }
+}"
+`;
+
+exports[`t-set slots with an t-set with a component in body 2`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2 = text(\`Blorg \`);
+    let b3 = callSlot(ctx, node, key, 'default', false, {});
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`t-set slots with an t-set with a component in body 3`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`Child\`);
+  }
+}"
+`;
+
+exports[`t-set slots with an unused t-set with a component in body 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { capture, isBoundary, withDefault, LazyValue } = helpers;
+  
+  function slot1(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx[\`v\`] = new LazyValue(value1, ctx, node);
+    return text(\` in slot \`);
+  }
+  
+  function value1(ctx, node, key = \\"\\") {
+    return component(\`Child\`, {}, key + \`__1\`, node, ctx);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return component(\`Child\`, {slots: {'default': {__render: slot1, __ctx: ctx1}}}, key + \`__2\`, node, ctx);
+  }
+}"
+`;
+
+exports[`t-set slots with an unused t-set with a component in body 2`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2 = text(\`Child \`);
+    let b3 = callSlot(ctx, node, key, 'default', false, {});
+    return multi([b2, b3]);
+  }
+}"
+`;
+
 exports[`t-set t-set can't alter component even if key in component 1`] = `
 "function anonymous(bdom, helpers
 ) {
@@ -174,3 +318,59 @@ exports[`t-set t-set outside modified in t-if 1`] = `
   }
 }"
 `;
+
+exports[`t-set t-set with a component in body 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { isBoundary, withDefault, LazyValue, safeOutput } = helpers;
+  
+  let block1 = createBlock(\`<div><div><block-child-0/></div></div>\`);
+  
+  function value1(ctx, node, key = \\"\\") {
+    return component(\`Child\`, {}, key + \`__1\`, node, ctx);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx[\`v\`] = new LazyValue(value1, ctx, node);
+    let b3 = safeOutput(ctx['v']);
+    return block1([], [b3]);
+  }
+}"
+`;
+
+exports[`t-set t-set with a component in body 2`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`Child\`);
+  }
+}"
+`;
+
+exports[`t-set t-set with something in body 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { isBoundary, withDefault, LazyValue, safeOutput } = helpers;
+  
+  let block1 = createBlock(\`<div><div><block-child-0/></div></div>\`);
+  let block2 = createBlock(\`<p>coucou</p>\`);
+  
+  function value1(ctx, node, key = \\"\\") {
+    return block2();
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx[\`v\`] = new LazyValue(value1, ctx, node);
+    let b3 = safeOutput(ctx['v']);
+    return block1([], [b3]);
+  }
+}"
+`;
diff --git a/tests/components/t_set.test.ts b/tests/components/t_set.test.ts
index 7027636e..f5db92c5 100644
--- a/tests/components/t_set.test.ts
+++ b/tests/components/t_set.test.ts
@@ -156,4 +156,113 @@ describe("t-set", () => {
     expect(fixture.innerHTML).toBe("<div><p>source</p><div>childcalled</div><p>source</p></div>");
     expect((child as any).iter).toBe("child");
   });
+
+  test("t-set with something in body", async () => {
+    class Comp extends Component {
+      static template = xml`
+        <div>
+          <t t-set="v">
+            <p>coucou</p>
+          </t>
+          <div><t t-out="v"/></div>
+        </div>`;
+    }
+
+    await mount(Comp, fixture);
+
+    expect(fixture.innerHTML).toBe("<div><div><p>coucou</p></div></div>");
+  });
+
+  test("t-set with a component in body", async () => {
+    class Child extends Component {
+      static template = xml`Child`;
+    }
+
+    class Comp extends Component {
+      static template = xml`
+        <div>
+          <t t-set="v">
+            <Child/>
+          </t>
+          <div><t t-out="v"/></div>
+        </div>`;
+      static components = { Child };
+    }
+
+    await mount(Comp, fixture);
+
+    expect(fixture.innerHTML).toBe("<div><div>Child</div></div>");
+  });
+
+  test("slots with an unused t-set with a component in body", async () => {
+    class Child extends Component {
+      static template = xml`Child <t t-slot="default"/>`;
+    }
+
+    class Comp extends Component {
+      static template = xml`
+            <Child>
+              <t t-set="v">
+                <Child/>
+              </t>
+              in slot
+            </Child>`;
+      static components = { Child };
+    }
+
+    await mount(Comp, fixture);
+
+    expect(fixture.innerHTML).toBe("Child  in slot ");
+  });
+
+  test("slots with a t-set with a component in body", async () => {
+    class C extends Component {
+      static template = xml`C`;
+    }
+    class Child extends Component {
+      static template = xml`Child <t t-slot="default"/>`;
+    }
+
+    class Comp extends Component {
+      static template = xml`
+            <Child>
+              <t t-set="v">
+                <C/>
+              </t>
+              in slot
+              <t t-out="v" />
+            </Child>`;
+      static components = { Child, C };
+    }
+
+    await mount(Comp, fixture);
+
+    expect(fixture.innerHTML).toBe("Child  in slot C");
+  });
+
+  test("slots with an t-set with a component in body", async () => {
+    class Child extends Component {
+      static template = xml`Child`;
+    }
+    class Blorg extends Component {
+      static template = xml`Blorg <t t-slot="default"/>`;
+    }
+
+    class Comp extends Component {
+      static template = xml`
+        <Blorg>
+          <t t-set="v">
+            <Child/>
+            <div>coffee</div>
+          </t>
+          tea
+          <t t-out="v"/>
+        </Blorg>`;
+      static components = { Child, Blorg };
+    }
+
+    await mount(Comp, fixture);
+
+    expect(fixture.innerHTML).toBe("Blorg  tea Child<div>coffee</div>");
+  });
 });
diff --git a/tests/helpers.ts b/tests/helpers.ts
index ae14ba9e..e80d0b68 100644
--- a/tests/helpers.ts
+++ b/tests/helpers.ts
@@ -78,7 +78,14 @@ export function snapshotTemplate(template: string) {
   expect(fn.toString()).toMatchSnapshot();
 }
 
-export function renderToBdom(template: string, context: any = {}, node: any = {}): BDom {
+export function renderToBdom(template: string, context: any = {}, node?: any): BDom {
+  if (!node) {
+    if (!context.__owl__) {
+      context.__owl__ = { component: context };
+    } else {
+      context.__owl__.component = context;
+    }
+  }
   const fn = compile(template);
   if (shouldSnapshot && !snapshottedTemplates.has(template)) {
     snapshottedTemplates.add(template);
@@ -87,9 +94,9 @@ export function renderToBdom(template: string, context: any = {}, node: any = {}
   return fn(blockDom, UTILS)(context, node);
 }
 
-export function renderToString(template: string, context: any = {}): string {
+export function renderToString(template: string, context: any = {}, node?: any): string {
   const fixture = makeTestFixture();
-  const bdom = renderToBdom(template, context);
+  const bdom = renderToBdom(template, context, node);
   mount(bdom, fixture);
   return fixture.innerHTML;
 }