Improved JSDoc comments for type correctness.

.gitignore

@@ -6,6 +6,7 @@
 /coverage
 package-lock.json
 /test/ts/**/*.js
+.*.swp
 
 # Additional bundles
 /devtools.js

package.json

@@ -9,6 +9,7 @@
   "minified:main": "dist/preact.min.js",
   "types": "dist/preact.d.ts",
   "scripts": {
+    "checkJs": "tsc --allowJs --checkJs --noEmit --target ES6 src/*.js src/**/*.js",
     "clean": "rimraf dist/ devtools.js devtools.js.map debug.js debug.js.map test/ts/**/*.js",
     "copy-flow-definition": "copyfiles -f src/preact.js.flow dist",
     "copy-typescript-definition": "copyfiles -f src/preact.d.ts dist",
@@ -119,7 +120,7 @@
     "rollup-plugin-node-resolve": "^3.0.0",
     "sinon": "^4.4.2",
     "sinon-chai": "^3.0.0",
-    "typescript": "^2.9.0-rc",
+    "typescript": "^2.9.2",
     "uglify-js": "^2.7.5",
     "webpack": "^4.3.0"
   },

src/clone-element.js

@@ -1,12 +1,16 @@
 import { extend } from './util';
 import { h } from './h';
 
+/**
+ * @typedef {import('./vnode').VNode} VNode
+ */
+
 /**
  * Clones the given VNode, optionally adding attributes/props and replacing its
  * children.
- * @param {import('./vnode').VNode} vnode The virtual DOM element to clone
+ * @param {VNode} vnode The virtual DOM element to clone
  * @param {object} props Attributes/props to add when cloning
- * @param {Array<import('./vnode').VNode>} [rest] Any additional arguments will be used as replacement
+ * @param {Array<VNode>} [rest] Any additional arguments will be used as replacement
  *  children.
  */
 export function cloneElement(vnode, props) {

src/component.js

@@ -2,6 +2,11 @@ import { FORCE_RENDER } from './constants';
 import { extend } from './util';
 import { renderComponent } from './vdom/component';
 import { enqueueRender } from './render-queue';
+
+/**
+ * @typedef {import('./vnode').VNode} VNode
+ */
+
 /**
  * Base Component class.
  * Provides `setState()` and `forceUpdate()`, which trigger rendering.
@@ -79,7 +84,7 @@ extend(Component.prototype, {
 	 * @param {object} state The component's current state
 	 * @param {object} context Context object, as returned by the nearest
 	 *  ancestor's `getChildContext()`
-	 * @returns {import('./vnode').VNode | void}
+	 * @returns {VNode | void}
 	 */
 	render() {}
 

src/dom/index.js

@@ -1,9 +1,13 @@
 import { IS_NON_DIMENSIONAL } from '../constants';
 import options from '../options';
 
+/**
+ * @typedef {import('../component').Component} Component
+ */
+
 /**
  * A DOM event listener
- * @typedef {(e: Event) => void} EventListner
+ * @typedef {(e: Event) => void} EventListener
  */
 
 /**
@@ -15,8 +19,9 @@ import options from '../options';
  * Properties Preact adds to elements it creates
  * @typedef PreactElementExtensions
  * @property {string} [normalizedNodeName] A normalized node name to use in diffing
+ * @property {string} [splitText]
  * @property {EventListenerMap} [_listeners] A map of event listeners added by components to this DOM node
- * @property {import('../component').Component} [_component] The component that rendered this DOM node
+ * @property {Component} [_component] The component that rendered this DOM node
  * @property {function} [_componentConstructor] The constructor of the component that rendered this DOM node
  */
 

src/render-queue.js

@@ -2,15 +2,19 @@ import options from './options';
 import { defer } from './util';
 import { renderComponent } from './vdom/component';
 
+/**
+ * @typedef {import('./component').Component} Component
+ */
+
 /**
  * Managed queue of dirty components to be re-rendered
- * @type {Array<import('./component').Component>}
+ * @type {Array<Component>}
  */
 let items = [];
 
 /**
  * Enqueue a rerender of a component
- * @param {import('./component').Component} component The component to rerender
+ * @param {Component} component The component to rerender
  */
 export function enqueueRender(component) {
 	if (!component._dirty && (component._dirty = true) && items.push(component)==1) {

src/render.js

@@ -1,10 +1,15 @@
 import { diff } from './vdom/diff';
 
+/**
+ * @typedef {import('./vnode').VNode} VNode
+ * @typedef {import('./dom/index.js').PreactElement} PreactElement
+ */
+
 /**
  * Render JSX into a `parent` Element.
- * @param {import('./vnode').VNode} vnode A (JSX) VNode to render
- * @param {import('./dom').PreactElement} parent DOM element to render into
- * @param {import('./dom').PreactElement} [merge] Attempt to re-use an existing DOM tree rooted at
+ * @param {VNode} vnode A (JSX) VNode to render
+ * @param {PreactElement} parent DOM element to render into
+ * @param {PreactElement} [merge] Attempt to re-use an existing DOM tree rooted at
  *  `merge`
  * @public
  *

src/vdom/component-recycler.js

@@ -19,14 +19,18 @@ export function collectComponent(component) {
 	(components[name] || (components[name] = [])).push(component);
 }
 
+/**
+ * @typedef {Component} CustomComponent
+ * @property {function} render
+ */
 
 /**
  * Create a component. Normalizes differences between PFC's and classful
  * Components.
- * @param {function} Ctor The constructor of the component to create
+ * @param {(props, context) => void} Ctor The constructor of the component to create
  * @param {object} props The initial props of the component
  * @param {object} context The initial context of the component
- * @returns {import('../component').Component}
+ * @returns {Component}
  */
 export function createComponent(Ctor, props, context) {
 	let list = components[Ctor.name],
@@ -39,7 +43,8 @@ export function createComponent(Ctor, props, context) {
 	else {
 		inst = new Component(props, context);
 		inst.constructor = Ctor;
-		inst.render = doRender;
+		/** @type {CustomComponent} */(inst).render =
+			doRender;
 	}
 
 

src/vdom/component.js

@@ -7,9 +7,15 @@ import { diff, mounts, diffLevel, flushMounts, recollectNodeTree, removeChildren
 import { createComponent, collectComponent } from './component-recycler';
 import { removeNode } from '../dom/index';
 
+/**
+ * @typedef {import('../component').Component} Component
+ * @typedef {import('../dom/index.js').PreactElement} PreactElement
+ * @typedef {import('../vnode').VNode} VNode
+ */
+
 /**
  * Set a component's `props` and possibly re-render the component
- * @param {import('../component').Component} component The Component to set props on
+ * @param {Component} component The Component to set props on
  * @param {object} props The new props
  * @param {number} renderMode Render options - specifies how to re-render the component
  * @param {object} context The new context
@@ -60,7 +66,7 @@ export function setComponentProps(component, props, renderMode, context, mountAl
 /**
  * Render a Component, triggering necessary lifecycle events and taking
  * High-Order Components into account.
- * @param {import('../component').Component} component The component to render
+ * @param {Component} component The component to render
  * @param {number} [renderMode] render mode, see constants.js for available options.
  * @param {boolean} [mountAll] Whether or not to immediately mount all components
  * @param {boolean} [isChild] ?
@@ -212,11 +218,11 @@ export function renderComponent(component, renderMode, mountAll, isChild) {
 
 /**
  * Apply the Component referenced by a VNode to the DOM.
- * @param {import('../dom').PreactElement} dom The DOM node to mutate
- * @param {import('../vnode').VNode} vnode A Component-referencing VNode
+ * @param {PreactElement} dom The DOM node to mutate
+ * @param {VNode} vnode A Component-referencing VNode
  * @param {object} context The current context
  * @param {boolean} mountAll Whether or not to immediately mount all components
- * @returns {import('../dom').PreactElement} The created/mutated element
+ * @returns {PreactElement} The created/mutated element
  * @private
  */
 export function buildComponentFromVNode(dom, vnode, context, mountAll) {
@@ -240,7 +246,10 @@ export function buildComponentFromVNode(dom, vnode, context, mountAll) {
 			dom = oldDom = null;
 		}
 
-		c = createComponent(vnode.nodeName, props, context);
+		c = createComponent(
+			/** @type {(props, context) => void} */(vnode.nodeName),
+			props, context);
+
 		if (dom && !c.nextBase) {
 			c.nextBase = dom;
 			// passing dom/oldDom as nextBase will recycle it if unused, so bypass recycling on L229:
@@ -262,7 +271,7 @@ export function buildComponentFromVNode(dom, vnode, context, mountAll) {
 
 /**
  * Remove a component from the DOM and recycle it.
- * @param {import('../component').Component} component The Component instance to unmount
+ * @param {Component} component The Component instance to unmount
  * @private
  */
 export function unmountComponent(component) {