1 files changed, 54 insertions, 11 deletions

diff --git a/src/data/things/language.js b/src/data/things/language.js
index a3f861bd..d9151551 100644
--- a/src/data/things/language.js
+++ b/src/data/things/language.js
@@ -1,8 +1,9 @@
-import { Temporal, toTemporalInstant } from '@js-temporal/polyfill';
+import {Temporal, toTemporalInstant} from '@js-temporal/polyfill';
 
 import {withAggregate} from '#aggregate';
 import CacheableObject from '#cacheable-object';
 import {logWarn} from '#cli';
+import {input} from '#composite';
 import * as html from '#html';
 import {empty} from '#sugar';
 import {isLanguageCode} from '#validators';
@@ -16,6 +17,7 @@ import {
   isExternalLinkStyle,
 } from '#external-links';
 
+import {exposeConstant} from '#composite/control-flow';
 import {externalFunction, flag, name} from '#composite/wiki-properties';
 
 export const languageOptionRegex = /{(?<name>[A-Z0-9_]+)}/g;
@@ -127,6 +129,12 @@ export class Language extends Thing {
 
     // Expose only
 
+    isLanguage: [
+      exposeConstant({
+        value: input.value(true),
+      }),
+    ],
+
     onlyIfOptions: {
       flags: {expose: true},
       expose: {
@@ -135,6 +143,7 @@ export class Language extends Thing {
     },
 
     intl_date: this.#intlHelper(Intl.DateTimeFormat, {full: true}),
+    intl_dateYear: this.#intlHelper(Intl.DateTimeFormat, {year: 'numeric'}),
     intl_number: this.#intlHelper(Intl.NumberFormat),
     intl_listConjunction: this.#intlHelper(Intl.ListFormat, {type: 'conjunction'}),
     intl_listDisjunction: this.#intlHelper(Intl.ListFormat, {type: 'disjunction'}),
@@ -488,22 +497,44 @@ export class Language extends Thing {
     // or both are undefined, that's just blank content.
     const hasStart = startDate !== null && startDate !== undefined;
     const hasEnd = endDate !== null && endDate !== undefined;
-    if (!hasStart || !hasEnd) {
-      if (startDate === endDate) {
-        return html.blank();
-      } else if (hasStart) {
-        throw new Error(`Expected both start and end of date range, got only start`);
-      } else if (hasEnd) {
-        throw new Error(`Expected both start and end of date range, got only end`);
-      } else {
-        throw new Error(`Got mismatched ${startDate}/${endDate} for start and end`);
-      }
+    if (!hasStart && !hasEnd) {
+      return html.blank();
+    } else if (hasStart && !hasEnd) {
+      throw new Error(`Expected both start and end of date range, got only start`);
+    } else if (!hasStart && hasEnd) {
+      throw new Error(`Expected both start and end of date range, got only end`);
     }
 
     this.assertIntlAvailable('intl_date');
     return this.intl_date.formatRange(startDate, endDate);
   }
 
+  formatYear(date) {
+    if (date === null || date === undefined) {
+      return html.blank();
+    }
+
+    this.assertIntlAvailable('intl_dateYear');
+    return this.intl_dateYear.format(date);
+  }
+
+  formatYearRange(startDate, endDate) {
+    // formatYearRange expects both values to be present, but if both are null
+    // or both are undefined, that's just blank content.
+    const hasStart = startDate !== null && startDate !== undefined;
+    const hasEnd = endDate !== null && endDate !== undefined;
+    if (!hasStart && !hasEnd) {
+      return html.blank();
+    } else if (hasStart && !hasEnd) {
+      throw new Error(`Expected both start and end of date range, got only start`);
+    } else if (!hasStart && hasEnd) {
+      throw new Error(`Expected both start and end of date range, got only end`);
+    }
+
+    this.assertIntlAvailable('intl_dateYear');
+    return this.intl_dateYear.formatRange(startDate, endDate);
+  }
+
   formatDateDuration({
     years: numYears = 0,
     months: numMonths = 0,
@@ -842,6 +873,18 @@ export class Language extends Thing {
     }
   }
 
+  typicallyLowerCase(string) {
+    // Utter nonsense implementation, so this only works on strings,
+    // not actual HTML content, and may rudely disrespect *intentful*
+    // capitalization of whatever goes into it.
+
+    if (typeof string !== 'string') return string;
+    if (string.length <= 1) return string;
+    if (/^\S+?[A-Z]/.test(string)) return string;
+
+    return string[0].toLowerCase() + string.slice(1);
+  }
+
   // Utility function to quickly provide a useful string key
   // (generally a prefix) to stuff nested beneath it.
   encapsulate(...args) {