Implement isemail v4

.babelrc

@@ -0,0 +1,9 @@
+{
+  "presets": [
+    "@babel/flow"
+  ],
+  "plugins": [
+    "@babel/plugin-transform-flow-strip-types",
+    "@babel/plugin-transform-modules-commonjs"
+  ]
+}

.eslintignore

@@ -0,0 +1 @@
+/dist

.eslintrc.json

@@ -0,0 +1,3 @@
+{
+    "extends": "hapi"
+}

.flowconfig

@@ -0,0 +1,11 @@
+[ignore]
+
+[include]
+
+[libs]
+
+[lints]
+
+[options]
+
+[strict]

.gitignore

@@ -1,3 +1,4 @@
 /coverage.html
 /coverage.lcov
+/dist
 /node_modules

.lab.transform.js

@@ -0,0 +1,29 @@
+'use strict';
+
+const Babel = require('@babel/core');
+
+const internals = {
+    GEN_COV_HTML: !!process.env.GEN_COV_HTML
+};
+
+// Adapted from https://github.com/hapijs/lab/issues/338 and
+// https://github.com/nlf/lab-babel (which doesn't yet support Babel v7).
+module.exports = [{
+    ext: '.js',
+    transform(content, filename) {
+
+        if (filename.startsWith('node_modules')) {
+            return content;
+        }
+
+        return Babel.transformSync(content, {
+            auxiliaryCommentBefore: '$lab:coverage:off$',
+            auxiliaryCommentAfter: '$lab:coverage:on$',
+            filename,
+            retainLines: !internals.GEN_COV_HTML,
+            sourceFileName: filename,
+            sourceMap: internals.GEN_COV_HTML ? 'inline' : false,
+            sourceType: 'module'
+        }).code;
+    }
+}];

flow-typed/.eslintrc.json

@@ -0,0 +1,3 @@
+{
+    "extends": "../lib/.eslintrc.json"
+}

flow-typed/npm/punycode_v2.x.x.js

@@ -0,0 +1,84 @@
+// flow-typed signature: ff1199d785cbf7a22553277f393e5fb0
+// flow-typed version: <<STUB>>/punycode_v2.1.1/flow_v0.92.1
+
+// From
+// https://github.com/flow-typed/flow-typed/blob/9d7a8571fde3e7573486d8262a1b29dfe9ab2df8/definitions/npm/punycode_v2.1.x/flow_v0.30.x-/punycode_v2.1.x.js
+// because flow-typed wasn't cooperating.
+declare module 'punycode' {
+  /**
+   * Creates an array containing the numeric code points of each Unicode
+   * character in the string. While JavaScript uses UCS-2 internally,
+   * this function will convert a pair of surrogate halves (each of which
+   * UCS-2 exposes as separate characters) into a single code point,
+   * matching UTF-16.
+   * @param {String} string The Unicode input string (UCS-2).
+   * @return {Array} The new array of code points.
+   */
+  declare function ucs2decode(string: string): Array<number>;
+
+  /**
+   * Creates a string based on an array of numeric code points.
+   * @param {Array} codePoints The array of numeric code points.
+   * @return {String} The new Unicode string (UCS-2).
+   */
+  declare function ucs2encode(codePoints: Array<number>): string;
+
+  /**
+   * Converts a Punycode string of ASCII-only symbols to a string of Unicode
+   * symbols.
+   * @param {String} input The Punycode string of ASCII-only symbols.
+   * @return {String} The resulting string of Unicode symbols.
+   */
+  declare function decode(input: string): string;
+
+  /**
+   * Converts a string of Unicode symbols (e.g. a domain name label) to a
+   * Punycode string of ASCII-only symbols.
+   * @param {String} input The string of Unicode symbols.
+   * @return {String} The resulting Punycode string of ASCII-only symbols.
+   */
+  declare function encode(input: string): string;
+
+  /**
+   * Converts a Punycode string representing a domain name or an email address
+   * to Unicode. Only the Punycoded parts of the input will be converted, i.e.
+   * it doesn't matter if you call it on a string that has already been
+   * converted to Unicode.
+   * @param {String} input The Punycoded domain name or email address to
+   * convert to Unicode.
+   * @return {String} The Unicode representation of the given Punycode
+   * string.
+   */
+  declare function toUnicode(input: string): string;
+
+  /**
+   * Converts a Unicode string representing a domain name or an email address to
+   * Punycode. Only the non-ASCII parts of the domain name will be converted,
+   * i.e. it doesn't matter if you call it with a domain that's already in
+   * ASCII.
+   * @param {String} input The domain name or email address to convert, as a
+   * Unicode string.
+   * @return {String} The Punycode representation of the given domain name or
+   * email address.
+   */
+  declare function toASCII(input: string): string;
+
+  declare module.exports: {
+    /**
+     * A string representing the current Punycode.js version number.
+     */
+    version: string,
+    /**
+     * An object of methods to convert from JavaScript's internal character
+     * representation (UCS-2) to Unicode code points, and back.
+     */
+    ucs2: {
+      decode: typeof ucs2decode,
+      encode: typeof ucs2encode,
+    },
+    decode: typeof decode,
+    encode: typeof encode,
+    toASCII: typeof toASCII,
+    toUnicode: typeof toUnicode,
+  };
+}

lib/.eslintrc.json

@@ -0,0 +1,15 @@
+{
+    "extends": "../.eslintrc.json",
+    "globals": {
+        "$Keys": true,
+        "Iterable": true,
+        "IteratorResult": true
+    },
+    "parser": "babel-eslint",
+    "parserOptions": {
+        "sourceType": "module"
+    },
+    "plugins": [
+        "flowtype"
+    ]
+}

lib/constants.js

@@ -1,6 +1,6 @@
-'use strict';
+// @flow strict
 
-exports.categories = {
+export const categories = {
     valid: 1,
     dnsWarn: 7,
     rfc5321: 15,
@@ -10,7 +10,9 @@ exports.categories = {
     error: 255
 };
 
-exports.diagnoses = {
+export type CategoryName = $Keys<typeof categories>;
+
+export const diagnoses = {
 
     // Address is valid
 
@@ -89,3 +91,5 @@ exports.diagnoses = {
     errDotAfterDomainLiteral: 162,
     errMalformedUnicode: 163
 };
+
+export type DiagnosisName = $Keys<typeof diagnoses>;

lib/diagnoses.js

@@ -1,18 +1,21 @@
-'use strict';
+// @flow strict
 
 // Load modules
 
-const Constants = require('./constants');
+import * as Constants from './constants';
 
 /**
  * Diagnosis stores a diagnosis-index pair.
  */
 class Diagnosis {
+    type: number;
+    index: number | null;
+
     /**
-     * @param {number} type The diagnostic code.
-     * @param {number} index The index of the diagnosis.
+     * @param type The diagnostic code.
+     * @param index The index of the diagnosis.
      */
-    constructor(type, index) {
+    constructor(type: number, index: number | null) {
 
         this.type = type;
         this.index = index;
@@ -24,7 +27,10 @@ class Diagnosis {
  * Diagnoses tracks a set of diagnostic codes for a string, along with their
  * positions in the string.
  */
-class Diagnoses {
+export default class Diagnoses {
+    _diagnoses: Diagnosis[];
+    _worstDiagnosis: Diagnosis | null;
+
     constructor() {
 
         this._diagnoses = [];
@@ -34,10 +40,11 @@ class Diagnoses {
     /**
      * Report the given diagnosis at the given index.
      *
-     * @param {number} type The diagnosis to report.
-     * @param {number} index The
+     * @param type The diagnosis to report.
+     * @param index The string offset in the input where the diagnosis occurs,
+     *   if applicable.
      */
-    diagnose(type, index) {
+    diagnose(type: number, index: number | null = null) {
 
         const diagnosis = new Diagnosis(type, index);
 
@@ -51,22 +58,21 @@ class Diagnoses {
     /**
      * Check whether the given diagnosis has been reported.
      *
-     * @param {number} queryType The diagnosis to query.
-     * @return {boolean} Whether the diagnosis has been reported.
+     * @param queryType The diagnosis to query.
+     * @return Whether the diagnosis has been reported.
      */
-    hasDiagnosis(queryType) {
+    hasDiagnosis(queryType: number): boolean {
 
         return this._diagnoses.some(({ type }) => type === queryType);
     }
 
     /**
      * Get the worst diagnosis encountered.
      *
-     * @param {Set<number>=} exclusions The set of diagnoses to exclude per the
-     *   configuration.
-     * @return {?Diagnosis} The worst diagnosis.
+     * @param exclusions The set of diagnoses to exclude per the configuration.
+     * @return The worst diagnosis.
      */
-    getWorstDiagnosis(exclusions = new Set()) {
+    getWorstDiagnosis(exclusions: Set<number> = new Set()): Diagnosis | null {
 
         // Use the precomputed worst diagnosis if it's not excluded.
         if (!this._worstDiagnosis || !exclusions.has(this._worstDiagnosis.type)) {
@@ -88,11 +94,10 @@ class Diagnoses {
      * For compatibility with existing versions of isemail, this function gets
      * the first fatal diagnosis, or the worst non-fatal diagnosis.
      *
-     * @param {Set<number>} exclusions The set of diagnoses to exclude per the
-     *   configuration.
-     * @return {?Diagnosis} The backwards-compatible diagnosis.
+     * @param exclusions The set of diagnoses to exclude per the configuration.
+     * @return The backwards-compatible diagnosis.
      */
-    getLegacyDiagnosis(exclusions) {
+    getLegacyDiagnosis(exclusions: Set<number>): Diagnosis | null {
 
         const firstFatalDiagnosis = this._diagnoses.find(({ type }) => type >= Constants.categories.rfc5322 && !exclusions.has(type));
 
@@ -103,6 +108,3 @@ class Diagnoses {
         return this.getWorstDiagnosis(exclusions);
     }
 }
-
-
-module.exports = Diagnoses;