v-slot is always undefined in VueJS

Here is the problem. Root view:

<template>
  <div class="home">
    <Grid :rows=3 :cols=4>
      <GridItem :x=1 :y=1 />
      <GridItem :x=2 :y=1 />
    </Grid>
  </div>
</template>

<script>
import Grid from '@/components/Grid'
import GridItem from '@/components/GridItem'

export default {
  name: 'Home',
  components: {
    Grid,
    GridItem
  }
}
</script>

Grid component (container):

<template>
  <div class="grid">
    <slot v-bind="testData"></slot>
  </div>
</template>

<script>
export default {
  name: 'Grid',
  data() {
    return {
      testData: 'test'
    }
  },
  props: {
    rows: Number,
    cols: Number
  }
}
</script>

And finally grid item component:

<template v-slot="slotProps">
  <div class="grid-item">
      {{x}} {{y}} {{slotProps.testData}}
  </div>
</template>

<script>
export default {
  name: 'GridItem',
  props: {
    x: Number,
    y: Number
  }
}
</script>

I’m getting the error: GridItem.vue Uncaught (in promise) TypeError: Cannot read property ‘testData’ of undefined. I’m cracked my head trying to understand what’s going wrong. Need help, thanks for your time.

Answer

Get your slot props in Home component:

<template>
  <div class="home">
    <Grid :rows=3 :cols=4 v-slot="{ testData }">
      <GridItem :x=1 :y=1 :test-data="testData" />
      <GridItem :x=2 :y=1 :test-data="testData" />
    </Grid>
  </div>
</template>