feat: Support ES5 environments

.browserslistrc

@@ -0,0 +1,6 @@
+ie 11
+edge >= 14
+firefox >= 52
+chrome >= 49
+safari >= 10
+node 10.0

.changeset/tasty-shrimps-juggle.md

@@ -0,0 +1,5 @@
+---
+"dom-accessibility-api": minor
+---
+
+Support ES5 environments

.gitignore

@@ -5,3 +5,4 @@ tests/cypress/videos
 # jest results
 /junit.xml
 /coverage
+/yarn-error.log

README.md

@@ -18,6 +18,19 @@ import { computeAccessibleName } from "dom-accessibility-api";
 I'm not an editor of any of the referenced specs (nor very experience with using them) so if you got any insights, something catches
 your eye please open an issue.
 
+## Supported environments
+
+```bash
+ie 11
+edge >= 14
+firefox >= 52
+chrome >= 49
+safari >= 10
+node 10.0
+```
+
+or check the published `.browserslistrc`
+
 ## progress
 
 Using https://github.com/web-platform-tests/wpt. Be sure to init submodules when

azure-pipelines.yml

@@ -22,6 +22,9 @@ steps:
   - script: yarn lint
     displayName: "Lint code"
 
+  - script: yarn test:types
+    displayName: "Test types"
+
   - script: |
       yarn build
     displayName: "Build"

package.json

@@ -8,17 +8,25 @@
 		"type": "git",
 		"url": "https://github.com/eps1lon/dom-accessibility-api.git"
 	},
+	"dependencies": {
+		"core-js-pure": "^3.6.4"
+	},
 	"files": [
+		".browserslistrc",
 		"dist/"
 	],
 	"scripts": {
-		"build": "tsc -p tsconfig.json",
+		"build": "yarn build:clean && yarn build:source && yarn build:types",
+		"build:clean": "rimraf dist",
+		"build:source": "babel sources --extensions \".ts\" --ignore \"**/__tests__/**/*\" --out-dir dist/ --source-maps",
+		"build:types": "tsc -p tsconfig.json --emitDeclarationOnly",
 		"format": "prettier \"**/*.{json,js,md,ts,yml}\" --write --ignore-path .prettierignore",
 		"lint": "eslint --report-unused-disable-directives \"sources/**/*.ts\"",
 		"release:prepare": "yarn changeset version",
 		"release": "yarn changeset publish",
 		"test": "jest",
 		"test:ci": "jest --ci --config jest.ci.config.js --runInBand",
+		"test:types": "tsc -p tsconfig.json --noEmit",
 		"test:wpt:jsdom": "mocha tests/wpt-jsdom/run-wpts.js",
 		"test:wpt:browser": "concurrently --success first --kill-others \"yarn test:wpt:browser:run\" \"yarn test:wpt:browser:server\"",
 		"test:wpt:browser:run": "cypress run --project tests",
@@ -29,14 +37,15 @@
 		"wpt:update": "git submodule update --recursive --remote && cd tests/wpt && python wpt.py manifest --path ../wpt-jsdom/wpt-manifest.json"
 	},
 	"devDependencies": {
+		"@babel/cli": "^7.8.4",
 		"@babel/core": "^7.8.4",
 		"@babel/preset-env": "^7.8.4",
 		"@babel/preset-typescript": "^7.8.3",
 		"@changesets/cli": "^2.5.2",
 		"@testing-library/dom": "^6.15.0",
 		"@types/jest": "^25.1.4",
-		"@typescript-eslint/parser": "^2.22.0",
 		"@typescript-eslint/eslint-plugin": "^2.22.0",
+		"@typescript-eslint/parser": "^2.22.0",
 		"concurrently": "^5.1.0",
 		"cypress": "^4.1.0",
 		"eslint": "^6.8.0",
@@ -53,6 +62,7 @@
 		"q": "^1.5.1",
 		"request": "^2.88",
 		"request-promise-native": "^1.0.8",
+		"rimraf": "^3.0.2",
 		"serve": "^11.3.0",
 		"typescript": "^3.8.3"
 	},

sources/accessible-name.ts

@@ -1,7 +1,8 @@
 /**
  * implements https://w3c.github.io/accname/
  */
-
+import ArrayFrom from "core-js-pure/features/array/from";
+import Set from "core-js-pure/stable/set";
 import getRole from "./getRole";
 import {
 	isElement,
@@ -135,7 +136,7 @@ function idRefs(node: Node, attributeName: string): Element[] {
  * @param node
  */
 function queryChildNodes(node: Node): Node[] {
-	return Array.from(node.childNodes).concat(idRefs(node, "aria-owns"));
+	return ArrayFrom(node.childNodes).concat(idRefs(node, "aria-owns"));
 }
 
 /**
@@ -192,7 +193,7 @@ function querySelectorAllSubtree(
 	const elements = [];
 
 	for (const root of [element, ...idRefs(element, "aria-owns")]) {
-		elements.push(...Array.from(root.querySelectorAll(selectors)));
+		elements.push(...ArrayFrom(root.querySelectorAll(selectors)));
 	}
 
 	return elements;
@@ -381,7 +382,7 @@ export function computeAccessibleName(
 		}
 
 		consultedNodes.add(input);
-		return Array.from(labels)
+		return ArrayFrom(labels)
 			.map(element => {
 				return computeTextAlternative(element, {
 					isEmbeddedInLabel: true,
@@ -477,7 +478,7 @@ export function computeAccessibleName(
 					// defined per test `name_heading_combobox`
 					return isHTMLInputElement(current) ? current.value : "";
 				}
-				return Array.from(selectedOptions)
+				return ArrayFrom(selectedOptions)
 					.map(selectedOption => {
 						return computeTextAlternative(selectedOption, {
 							isEmbeddedInLabel: context.isEmbeddedInLabel,

sources/core-js-pure.d.ts

@@ -0,0 +1,99 @@
+// copied from https://github.com/microsoft/TypeScript/blob/eaeee9cc31bdc3a16f982a2e7b784573c977fdfa/lib/
+// but with `unknown` instead of `any`
+interface IteratorYieldResult<TYield> {
+	done?: false;
+	value: TYield;
+}
+
+interface IteratorReturnResult<TReturn> {
+	done: true;
+	value: TReturn;
+}
+
+type IteratorResult<T, TReturn = unknown> =
+	| IteratorYieldResult<T>
+	| IteratorReturnResult<TReturn>;
+
+interface Iterator<T, TReturn = unknown, TNext = undefined> {
+	// NOTE: 'next' is defined using a tuple to ensure we report the correct assignability errors in all places.
+	next(...args: [] | [TNext]): IteratorResult<T, TReturn>;
+	return?(value?: TReturn): IteratorResult<T, TReturn>;
+	throw?(e?: unknown): IteratorResult<T, TReturn>;
+}
+
+interface Iterable<T> {
+	[Symbol.iterator](): Iterator<T>;
+}
+
+interface IterableIterator<T> extends Iterator<T> {
+	[Symbol.iterator](): IterableIterator<T>;
+}
+interface SymbolConstructor {
+	/**
+	 * A method that returns the default iterator for an object. Called by the semantics of the
+	 * for-of statement.
+	 */
+	readonly iterator: symbol;
+}
+
+declare const Symbol: SymbolConstructor;
+
+declare module "core-js-pure/stable/set" {
+	interface Set<T> {
+		add(value: T): this;
+		clear(): void;
+		delete(value: T): boolean;
+		forEach(
+			callbackfn: (value: T, value2: T, set: Set<T>) => void,
+			thisArg?: unknown
+		): void;
+		has(value: T): boolean;
+		readonly size: number;
+	}
+
+	interface Set<T> {
+		/** Iterates over values in the set. */
+		[Symbol.iterator](): IterableIterator<T>;
+		/**
+		 * Returns an iterable of [v,v] pairs for every value `v` in the set.
+		 */
+		entries(): IterableIterator<[T, T]>;
+		/**
+		 * Despite its name, returns an iterable of the values in the set,
+		 */
+		keys(): IterableIterator<T>;
+
+		/**
+		 * Returns an iterable of values in the set.
+		 */
+		values(): IterableIterator<T>;
+	}
+
+	interface SetConstructor {
+		new <T = unknown>(values?: readonly T[] | null): Set<T>;
+		readonly prototype: Set<unknown>;
+	}
+
+	const Set: SetConstructor;
+	export default Set;
+}
+
+declare module "core-js-pure/features/array/from" {
+	/**
+	 * Creates an array from an iterable object.
+	 * @param iterable An iterable object to convert to an array.
+	 */
+	export default function from<T>(iterable: Iterable<T> | ArrayLike<T>): T[];
+
+	/**
+	 * Creates an array from an iterable object.
+	 * @param iterable An iterable object to convert to an array.
+	 * @param mapfn A mapping function to call on every element of the array.
+	 * @param thisArg Value of 'this' used to invoke the mapfn.
+	 */
+	export default function from<T, U>(
+		iterable: Iterable<T> | ArrayLike<T>,
+		mapfn: (v: T, k: number) => U,
+		thisArg?: unknown
+	): U[];
+}

tsconfig.json

@@ -2,11 +2,11 @@
 	"compilerOptions": {
 		/* Basic Options */
 		// "incremental": true,                   /* Enable incremental compilation */
-		"target": "es6" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */,
+		"target": "es5" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */,
 		"module": "commonjs" /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */,
 		"lib": [
-			"dom",
-			"es6"
+			"ES5",
+			"DOM"
 		] /* Specify library files to be included in the compilation. */,
 		// "allowJs": true,                       /* Allow javascript files to be compiled. */
 		// "checkJs": true,                       /* Report errors in .js files. */
@@ -23,7 +23,8 @@
 		// "noEmit": true,                        /* Do not emit outputs. */
 		// "importHelpers": true,                 /* Import emit helpers from 'tslib'. */
 		// "downlevelIteration": true,            /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
-		// "isolatedModules": true,               /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
+		/* since we transpile with babel */
+		"isolatedModules": true /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */,
 
 		/* Strict Type-Checking Options */
 		"strict": true /* Enable all strict type-checking options. */,
@@ -47,7 +48,8 @@
 		// "paths": {},                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
 		// "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
 		// "typeRoots": [],                       /* List of folders to include type definitions from. */
-		// "types": [],                           /* Type declaration files to be included in compilation. */
+		/* make sure `@types/node` is ignored */
+		"types": [] /* Type declaration files to be included in compilation. */,
 		// "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
 		"esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
 		// "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
@@ -62,6 +64,6 @@
 		/* Experimental Options */
 		// "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
 		// "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */
-		"skipLibCheck": true
+		"skipLibCheck": false
 	}
 }