Implement the es-shim-api interface

Author: nicolo-ribaudo

.editorconfig

@@ -0,0 +1,6 @@
+root = true
+
+[*]
+indent_style = tab
+end_of_line = lf
+insert_final_newline = true

.gitignore

@@ -3,6 +3,7 @@ coverage
 
 # Installed npm modules
 node_modules
+package-lock.json
 
 # Folder view configuration files
 .DS_Store

.npmrc

@@ -0,0 +1 @@
+package-lock=false

auto.js

@@ -0,0 +1,3 @@
+/*! https://mths.be/codepointat v1.0.0 by @mathias */
+
+require('./shim')();

codepointat.js

@@ -0,0 +1,34 @@
+/*! https://mths.be/codepointat v1.0.0 by @mathias */
+
+'use strict';
+
+var callBound = require('es-abstract/helpers/callBound');
+var RequireObjectCoercible = require('es-abstract/2019/RequireObjectCoercible');
+var ToString = require('es-abstract/2019/ToString');
+var ToInteger = require('es-abstract/2019/ToInteger');
+var StringCharCodeAt = callBound('String.prototype.charCodeAt');
+
+module.exports = function codePointAt(position) {
+	var O = RequireObjectCoercible(this);
+	var string = ToString(O);
+	var size = string.length;
+	var index = ToInteger(position);
+	// Account for out-of-bounds indices:
+	if (index < 0 || index >= size) {
+		return undefined;
+	}
+	// Get the first code unit
+	var first = StringCharCodeAt(string, index);
+	var second;
+	if ( // check if it’s the start of a surrogate pair
+		first >= 0xD800 && first <= 0xDBFF && // high surrogate
+		size > index + 1 // there is a next code unit
+	) {
+		second = StringCharCodeAt(string, index + 1);
+		if (second >= 0xDC00 && second <= 0xDFFF) { // low surrogate
+			// https://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
+			return (first - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
+		}
+	}
+	return first;
+};

implementation.js

@@ -0,0 +1,20 @@
+/*! https://mths.be/codepointat v1.0.0 by @mathias */
+
+'use strict';
+
+var callBind = require('es-abstract/helpers/callBind');
+var define = require('define-properties');
+
+var implementation = require('./implementation');
+var getPolyfill = require('./polyfill');
+var shim = require('./shim');
+
+var boundCodePointAt = callBind(implementation);
+
+define(boundCodePointAt, {
+	getPolyfill: getPolyfill,
+	implementation: implementation,
+	shim: shim
+});
+
+module.exports = boundCodePointAt;

index.js

@@ -3,7 +3,15 @@
 	"version": "0.2.1",
 	"description": "A robust & optimized `String.prototype.codePointAt` polyfill, based on the ECMAScript 6 specification.",
 	"homepage": "https://mths.be/codepointat",
-	"main": "codepointat.js",
+	"main": "index.js",
+    "exports": {
+		".": "./index.js",
+		"./auto": "./auto.js",
+		"./shim": "./shim.js",
+		"./getPolyfill": "./getPolyfill.js",
+		"./implementation": "./implementation.js",
+		"./package.json": "./package.json"
+	},
 	"keywords": [
 		"string",
 		"unicode",
@@ -28,5 +36,12 @@
 	"scripts": {
 		"test": "node tests/tests.js",
 		"cover": "istanbul cover --report html --verbose --dir coverage tests/tests.js"
+	},
+    "dependencies": {
+		"define-properties": "^1.1.3",
+		"es-abstract": "^1.17.5"
+    },
+	"devDependencies": {
+		"istanbul": "^0.4.5"
 	}
 }

package.json

@@ -0,0 +1,9 @@
+/*! https://mths.be/codepointat v1.0.0 by @mathias */
+
+'use strict';
+
+var implementation = require('./implementation');
+
+module.exports = function getPolyfill() {
+	return String.prototype.codePointAt || implementation;
+};

polyfill.js

@@ -0,0 +1,17 @@
+/*! https://mths.be/codepointat v1.0.0 by @mathias */
+
+'use strict';
+
+var define = require('define-properties');
+
+var getPolyfill = require('./polyfill');
+
+module.exports = function shimCodePointAt() {
+	var polyfill = getPolyfill();
+
+	if (String.prototype.codePointAt !== polyfill) {
+		define(String.prototype, { codePointAt: polyfill });
+	}
+
+	return polyfill;
+}