3 files changed, 54 insertions, 10 deletions

diff --git a/src/data/things/language.js b/src/data/things/language.js
index 646eb6d1..70481299 100644
--- a/src/data/things/language.js
+++ b/src/data/things/language.js
@@ -1,5 +1,13 @@
-import {Tag} from '#html';
 import {isLanguageCode} from '#validators';
+import {Tag} from '#html';
+
+import {
+  getExternalLinkStringOfStyleFromDescriptors,
+  getExternalLinkStringsFromDescriptors,
+  isExternalLinkContext,
+  isExternalLinkSpec,
+  isExternalLinkStyle,
+} from '#external-links';
 
 import {
   externalFunction,
@@ -72,6 +80,13 @@ export class Language extends Thing {
       update: {validate: (t) => typeof t === 'object'},
     },
 
+    // List of descriptors for providing to external link utilities when using
+    // language.formatExternalLink - refer to util/external-links.js for info.
+    externalLinkSpec: {
+      flags: {update: true, expose: true},
+      update: {validate: isExternalLinkSpec},
+    },
+
     // Update only
 
     escapeHTML: externalFunction(),
@@ -299,6 +314,29 @@ export class Language extends Thing {
       : duration;
   }
 
+  formatExternalLink(url, {
+    style = 'normal',
+    context = 'generic',
+  } = {}) {
+    if (!this.externalLinkSpec) {
+      throw new TypeError(`externalLinkSpec unavailable`);
+    }
+
+    isExternalLinkContext(context);
+
+    if (style === 'all') {
+      return getExternalLinkStringsFromDescriptors(url, this.externalLinkSpec, {
+        language: this,
+        context,
+      });
+    }
+
+    return getExternalLinkStringOfStyleFromDescriptors(url, style, this.externalLinkSpec, {
+      language: this,
+      context,
+    });
+  }
+
   formatIndex(value) {
     this.assertIntlAvailable('intl_pluralOrdinal');
     return this.formatString('count.index.' + this.intl_pluralOrdinal.select(value), {index: value});
diff --git a/src/data/things/track.js b/src/data/things/track.js
index 8d310611..f6320677 100644
--- a/src/data/things/track.js
+++ b/src/data/things/track.js
@@ -24,6 +24,7 @@ import {
 
 import {
   additionalFiles,
+  additionalNameList,
   commentary,
   commentatorArtists,
   contributionList,
@@ -63,6 +64,7 @@ export class Track extends Thing {
 
     name: name('Unnamed Track'),
     directory: directory(),
+    additionalNames: additionalNameList(),
 
     duration: duration(),
     urls: urls(),
diff --git a/src/data/things/validators.js b/src/data/things/validators.js
index 569a7b34..55eedbcf 100644
--- a/src/data/things/validators.js
+++ b/src/data/things/validators.js
@@ -101,7 +101,10 @@ export function isStringNonEmpty(value) {
 }
 
 export function optional(validator) {
-  return value => value === null || value === undefined || validator(value);
+  return value =>
+    value === null ||
+    value === undefined ||
+    validator(value);
 }
 
 // Complex types (non-primitives)
@@ -341,20 +344,14 @@ export function validateProperties(spec) {
 
 export const isContribution = validateProperties({
   who: isArtistRef,
-  what: (value) =>
-    value === undefined ||
-    value === null ||
-    isStringNonEmpty(value),
+  what: optional(isStringNonEmpty),
 });
 
 export const isContributionList = validateArrayItems(isContribution);
 
 export const isAdditionalFile = validateProperties({
   title: isString,
-  description: (value) =>
-    value === undefined ||
-    value === null ||
-    isString(value),
+  description: optional(isStringNonEmpty),
   files: validateArrayItems(isString),
 });
 
@@ -432,6 +429,13 @@ export function isURL(string) {
   return true;
 }
 
+export const isAdditionalName = validateProperties({
+  name: isName,
+  annotation: optional(isStringNonEmpty),
+});
+
+export const isAdditionalNameList = validateArrayItems(isAdditionalName);
+
 export function validateReference(type = 'track') {
   return (ref) => {
     isStringNonEmpty(ref);