feat: new lifecycle properties

Author: sastan

README.md

@@ -52,6 +52,69 @@ And then grab it off the global like so:
 ```js
 const Fragment = svelteFragment
 ```
+
+## Usage
+
+> The examples below are using [svelte-jsx](https://www.npmjs.com/package/svelte-jsx) for the jsx syntax support.
+
+```js
+import Fragment from 'svelte-fragment-component'
+
+const Lifecycle = (
+  <Fragment
+    onCreate={() => {}}
+    onMount={() => {}}
+    beforeUpdate={() => {}}
+    afterUpdate={() => {}}
+    onDestroy={() => {}}
+  >
+    some content
+  </Fragment>
+)
+```
+
+This allows to simplify testing of [context API](https://svelte.dev/docs#setContext):
+
+```js
+import Fragment from 'svelte-fragment-component'
+import { setContext } from 'svelte'
+
+const Lifecycle = (
+  <Fragment
+    onCreate={() => {
+      setContext('some context key', theValue)
+    }}
+  >
+    children can now access this context value
+  </Fragment>
+)
+
+// or using the context property
+const Lifecycle = (
+  <Fragment context={{ 'some context key': theValue }}>
+    children can now access this context value
+  </Fragment>
+)
+```
+
+## API
+
+The component renders only the default slot children.
+
+### Properties
+
+> All properties are optional.
+
+- `context`: an key-value object where each pair is passed to [setContext](https://svelte.dev/docs#setContext)
+
+Except for `onCreate` these functions are passed to their corresponding svelte lifecycle method and have the same call signature `({ props }): void` where `props` are the `$$restProps`:
+
+- `onCreate`: called during component initialization
+- [onMount](https://svelte.dev/docs#onMount)
+- [beforeUpdate](https://svelte.dev/docs#beforeUpdate)
+- [afterUpdate](https://svelte.dev/docs#afterUpdate)
+- [onDestroy](https://svelte.dev/docs#onDestroy)
+
 ## Support
 
 This project is free and open-source, so if you think this project can help you or anyone else, you may [star it on GitHub](https://github.com/sastan/svelte-fragment-component). Feel free to [open an issue](https://github.com/sastan/svelte-fragment-component/issues) if you have any idea, question, or you've found a bug.

package.json

@@ -54,7 +54,6 @@
   },
   "homepage": "https://github.com/sastan/svelte-fragment-component#readme",
   "devDependencies": {
-    "@jest/globals": "^26.0.1",
     "@rollup/plugin-commonjs": "^13.0.0",
     "@rollup/plugin-node-resolve": "^8.0.1",
     "@testing-library/jest-dom": "^5.7.0",

src/fragment.svelte

@@ -1 +1,29 @@
+<script>
+  import * as Svelte from 'svelte'
+
+  export let context = null
+  export let onCreate = null
+  export let onMount = null
+  export let beforeUpdate = null
+  export let afterUpdate = null
+  export let onDestroy = null
+
+  if (context) {
+    Object.keys(context).forEach((key) => {
+      Svelte.setContext(key, context[key])
+    })
+  }
+
+  if (onCreate) bind(onCreate)()
+
+  if (onMount) Svelte.onMount(bind(onMount))
+  if (beforeUpdate) Svelte.beforeUpdate(bind(beforeUpdate))
+  if (afterUpdate) Svelte.afterUpdate(bind(afterUpdate))
+  if (onDestroy) Svelte.onDestroy(bind(onDestroy))
+
+  function bind(callback) {
+    return () => callback({ props: $$restProps })
+  }
+</script>
+
 <slot></slot>

src/fragment.test.js

@@ -1,10 +1,79 @@
-const { expect, test } = require('@jest/globals')
-const { render } = require('@testing-library/svelte')
+const { render, act } = require('@testing-library/svelte')
+const { getContext } = require('svelte')
 
 const WithChilds = require('./__fixtures__/with-childs.svelte')
+const Fragment = require('./fragment.svelte')
 
 test('renders all childs', () => {
   const { container } = render(WithChilds)
 
   expect(container.innerHTML).toMatch('<div>A<span>B</span>C</div>')
 })
+
+test('calls onCreate', () => {
+  const onCreate = jest.fn()
+
+  render(Fragment, { props: { onCreate, a: 1 } })
+
+  expect(onCreate).toHaveBeenCalledWith({ props: { a: 1 } })
+})
+
+test('calls onMount', () => {
+  const onMount = jest.fn()
+
+  render(Fragment, { props: { onMount, a: 1 } })
+
+  expect(onMount).toHaveBeenCalledWith({ props: { a: 1 } })
+})
+
+test('calls beforeUpdate', async () => {
+  const beforeUpdate = jest.fn()
+
+  const { component } = render(Fragment, { props: { beforeUpdate, a: 1 } })
+
+  expect(beforeUpdate).toHaveBeenCalledWith({ props: { a: 1 } })
+
+  await act(() => component.$set({ b: 2 }))
+
+  expect(beforeUpdate).toHaveBeenCalledWith({ props: { a: 1, b: 2 } })
+})
+
+test('calls afterUpdate', async () => {
+  const afterUpdate = jest.fn()
+
+  const { component } = render(Fragment, { props: { afterUpdate, a: 1 } })
+
+  expect(afterUpdate).toHaveBeenCalledWith({ props: { a: 1 } })
+
+  await act(() => component.$set({ b: 2 }))
+
+  expect(afterUpdate).toHaveBeenCalledWith({ props: { a: 1, b: 2 } })
+})
+
+test('calls onDestroy', async () => {
+  const onDestroy = jest.fn()
+
+  const { component } = render(Fragment, { props: { onDestroy, a: 1 } })
+
+  await act(() => component.$destroy())
+
+  expect(onDestroy).toHaveBeenCalledWith({ props: { a: 1 } })
+})
+
+test('create context', () => {
+  let a
+  let b
+
+  render(Fragment, {
+    props: {
+      context: { a: 1, b: 2 },
+      onMount: () => {
+        a = getContext('a')
+        b = getContext('b')
+      },
+    },
+  })
+
+  expect(a).toBe(1)
+  expect(b).toBe(2)
+})