Add a11y-accessible-emoji

package.json

@@ -73,6 +73,7 @@
     "code-red": "0.1.1",
     "codecov": "^3.5.0",
     "css-tree": "1.0.0-alpha22",
+    "emoji-regex": "^8.0.0",
     "eslint": "^6.3.0",
     "eslint-plugin-import": "^2.18.2",
     "eslint-plugin-svelte3": "^2.7.3",

src/compiler/compile/nodes/Element.ts

@@ -1,3 +1,4 @@
+import emojiRegex from 'emoji-regex';
 import { is_void } from '../../utils/names';
 import Node from './shared/Node';
 import Attribute from './Attribute';
@@ -274,6 +275,7 @@ export default class Element extends Node {
 		this.validate_attributes();
 		this.validate_bindings();
 		this.validate_content();
+		this.validate_emoji();
 		this.validate_event_handlers();
 	}
 
@@ -671,6 +673,36 @@ export default class Element extends Node {
 		}
 	}
 
+	validate_emoji() {
+		if (this.children.length === 1) {
+			const child = this.children[0];
+			if (child.type === 'Text' && emojiRegex().test(child.data)) {
+
+				const isHidden = this.attributes.find(
+					(attribute: Attribute) => attribute.name === 'aria-hidden'
+				);
+				if (isHidden && (isHidden.is_true || isHidden.get_static_value() === "true")) {
+					return; // emoji is decorative
+				}
+
+				const hasLabel = this.attributes.find(
+					(attribute: Attribute) => attribute.name === 'aria-label' || attribute.name === 'aria-labelledby'
+				);
+				const role = this.attributes.find(
+					(attribute: Attribute) => attribute.name === 'role'
+				);
+				const isSpan = this.name === 'span';
+
+				if (!hasLabel || role.get_static_value() !== 'img' || isSpan === false) {
+					this.component.warn(this, {
+						code: `a11y-accessible-emoji`,
+						message: `A11y: Emojis should be wrapped in <span>, have role="img", and have an accessible description with aria-label or aria-labelledby. `
+					});
+				}
+			}
+		}
+	}
+
 	validate_event_handlers() {
 		const { component } = this;
 

test/validator/samples/a11y-accessible-emoji/input.svelte

@@ -0,0 +1,18 @@
+<div />
+<span />
+<span>No emoji here!</span>
+<span role="img" aria-label="Panda face">🐼</span>
+<span role="img" aria-label="Snowman">&#9731;</span>
+<span role="img" aria-labelledby="id1">🐼</span>
+<span role="img" aria-labelledby="id1">&#9731;</span>
+<span role="img" aria-labelledby="id1" aria-label="Snowman">&#9731;</span>
+<span aria-hidden="true">🐼</span>
+<span aria-hidden>🐼</span>
+<div aria-hidden="true">🐼</div>
+
+<span>🐼</span>
+<span>foo🐼bar</span>
+<span>foo 🐼 bar</span>
+<i role="img" aria-label="Panda face">🐼</i>
+<i role="img" aria-labelledby="id1">🐼</i>
+<span aria-hidden="false">🐼</span>

test/validator/samples/a11y-accessible-emoji/warnings.json

@@ -0,0 +1,92 @@
+[
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 13,
+			"column": 0,
+			"character": 424
+		},
+		"end": {
+			"line": 13,
+			"column": 15,
+			"character": 439
+		},
+		"pos": 424
+	},
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 14,
+			"column": 0,
+			"character": 440
+		},
+		"end": {
+			"line": 14,
+			"column": 21,
+			"character": 461
+		},
+		"pos": 440
+	},
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 15,
+			"column": 0,
+			"character": 462
+		},
+		"end": {
+			"line": 15,
+			"column": 23,
+			"character": 485
+		},
+		"pos": 462
+	},
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 16,
+			"column": 0,
+			"character": 486
+		},
+		"end": {
+			"line": 16,
+			"column": 44,
+			"character": 530
+		},
+		"pos": 486
+	},
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 17,
+			"column": 0,
+			"character": 531
+		},
+		"end": {
+			"line": 17,
+			"column": 42,
+			"character": 573
+		},
+		"pos": 531
+	},
+	{
+		"code": "a11y-accessible-emoji",
+		"message": "A11y: Emojis should be wrapped in <span>, have role=\"img\", and have an accessible description with aria-label or aria-labelledby. ",
+		"start": {
+			"line": 18,
+			"column": 0,
+			"character": 574
+		},
+		"end": {
+			"line": 18,
+			"column": 35,
+			"character": 609
+		},
+		"pos": 574
+	}
+]