feat: support for custom and slot elements (#2581)

src/dom/node-parser.ts

@@ -20,6 +20,9 @@ const parseNodeTree = (node: Node, parent: ElementContainer, root: ElementContai
         if (isTextNode(childNode) && childNode.data.trim().length > 0) {
             parent.textNodes.push(new TextContainer(childNode, parent.styles));
         } else if (isElementNode(childNode)) {
+            if (isSlotElement(childNode) && childNode.assignedNodes) {
+                childNode.assignedNodes().forEach((childNode) => parseNodeTree(childNode, parent, root));
+            } else {
                 const container = createContainer(childNode);
                 if (container.styles.isVisible()) {
                     if (createsRealStackingContext(childNode, container, root)) {
@@ -33,12 +36,20 @@ const parseNodeTree = (node: Node, parent: ElementContainer, root: ElementContai
                     }
 
                     parent.elements.push(container);
-                if (!isTextareaElement(childNode) && !isSVGElement(childNode) && !isSelectElement(childNode)) {
+                    childNode.slot;
+                    if (childNode.shadowRoot) {
+                        parseNodeTree(childNode.shadowRoot, container, root);
+                    } else if (
+                        !isTextareaElement(childNode) &&
+                        !isSVGElement(childNode) &&
+                        !isSelectElement(childNode)
+                    ) {
                         parseNodeTree(childNode, container, root);
                     }
                 }
             }
         }
+    }
 };
 
 const createContainer = (element: Element): ElementContainer => {
@@ -118,3 +129,4 @@ export const isStyleElement = (node: Element): node is HTMLStyleElement => node.
 export const isScriptElement = (node: Element): node is HTMLScriptElement => node.tagName === 'SCRIPT';
 export const isTextareaElement = (node: Element): node is HTMLTextAreaElement => node.tagName === 'TEXTAREA';
 export const isSelectElement = (node: Element): node is HTMLSelectElement => node.tagName === 'SELECT';
+export const isSlotElement = (node: Element): node is HTMLSlotElement => node.tagName === 'SLOT';

tests/reftests/webcomponents/autonomous-custom-element.js

@@ -0,0 +1,45 @@
+class AutonomousCustomElement extends HTMLElement {
+    constructor() {
+        super();
+
+        const shadow = this.attachShadow({mode: 'open'});
+        const wrapper = document.createElement('span');
+        wrapper.setAttribute('class', 'wrapper');
+
+        const info = document.createElement('span');
+        info.setAttribute('class', 'info');
+
+        info.textContent = this.getAttribute('text');
+
+        const img = document.createElement('img');
+        img.src = this.getAttribute('img');
+
+        // Create some CSS to apply to the shadow dom
+        const style = document.createElement('style');
+
+        style.textContent = `
+      .wrapper {
+        position: relative;
+      }
+      .info {
+        font-size: 0.8rem;
+        width: 200px;
+        display: inline-block;
+        border: 1px solid black;
+        padding: 10px;
+        background: white;
+        border-radius: 10px;
+      }
+      img {
+        width: 100px;
+      }
+    `;
+
+        shadow.appendChild(style);
+        shadow.appendChild(wrapper);
+        wrapper.appendChild(img);
+        wrapper.appendChild(info);
+    }
+}
+
+customElements.define('autonomous-custom-element', AutonomousCustomElement);

tests/reftests/webcomponents/slot-element.js

@@ -0,0 +1,51 @@
+customElements.define('summary-display',
+    class extends HTMLElement {
+        constructor() {
+            super();
+
+            const template = document.getElementById('summary-display-template');
+            const templateContent = template.content;
+
+            const shadowRoot = this.attachShadow({mode: 'open'});
+            shadowRoot.appendChild(templateContent.cloneNode(true));
+
+            const items = Array.from(this.querySelectorAll('li'));
+            const descriptions = Array.from(this.querySelectorAll('p'));
+
+            items.forEach(item => {
+                handleClick(item);
+            });
+
+            descriptions.forEach(description => {
+                updateDisplay(description, items[1]);
+            });
+
+            function handleClick(item) {
+                item.addEventListener('click', function() {
+                    items.forEach(item => {
+                        item.style.backgroundColor = 'white';
+                    });
+
+                    descriptions.forEach(description => {
+                        updateDisplay(description, item);
+                    });
+                });
+            }
+
+            function updateDisplay(description, item) {
+                description.removeAttribute('slot');
+
+                if(description.getAttribute('data-name') === item.textContent) {
+                    description.setAttribute('slot', 'choice');
+                    item.style.backgroundColor = '#bad0e4';
+                }
+            }
+
+            const slots = this.shadowRoot.querySelectorAll('slot');
+            slots[1].addEventListener('slotchange', function(e) {
+                const nodes = slots[1].assignedNodes();
+                console.log(`Element in Slot "${slots[1].name}" changed to "${nodes[0].outerHTML}".`);
+            });
+        }
+    }
+);

tests/reftests/webcomponents/webcomponents.html

@@ -0,0 +1,53 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Web components tests</title>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
+    <script type="text/javascript" src="../../test.js"></script>
+    <style>
+
+    </style>
+</head>
+<body>
+<div>
+    <h1>Autonomous custom element</h1>
+    <autonomous-custom-element img="../../assets/image.jpg" text="This is text"></autonomous-custom-element>
+    <h1>Slot element</h1>
+    <summary-display>
+        <ul slot="master-list">
+            <li>Apples</li>
+            <li>Pears</li>
+            <li>Bananas</li>
+            <li>Oranges</li>
+            <li>Peaches</li>
+            <li>Strawberries</li>
+            <li>Blueberries</li>
+        </ul>
+
+        <p data-name="Apples">A common, sweet, crunchy fruit, usually green or yellow in color.</p>
+        <p data-name="Pears">A fairly common, sweet, usually green fruit, usually softer than Apples.</p>
+        <p data-name="Bananas">A long, curved, yellow fruit, with a fairly gentle flavor.</p>
+        <p data-name="Oranges">Orange in color, usually sweet but can be sharp, often contains pips.</p>
+        <p data-name="Peaches">An orange fruit with big stone in the middle, and sweet, juicy flesh.</p>
+        <p data-name="Strawberries">A red fruit with yellow seeds on the outside; has a sweet flavor and a pretty shape.</p>
+        <p data-name="Blueberries">They are berries and they are blue; sweet in flavor, small in size, round.</p>
+    </summary-display>
+
+    <template id="summary-display-template">
+        <article>
+            <div>
+                <slot name="master-list"></slot>
+            </div>
+            <div>
+                <slot name="choice"></slot>
+            </div>
+        </article>
+    </template>
+
+    <script src="autonomous-custom-element.js"></script>
+    <script src="slot-element.js"></script>
+</div>
+
+
+</body>
+</html>