LibUnicode: Do not generate data for "generic" calendars

This is not a calendar supported by ECMA-402, so let's not waste space
with its data.

Further, don't generate "gregorian" as a valid Unicode locale extension
keyword. It's an invalid type identifier, thus cannot be used in locales
such as "en-u-ca-gregorian".

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeDateTimeFormat.cpp

@@ -151,6 +151,11 @@ static ErrorOr<void> parse_calendars(String locale_calendars_path, UnicodeLocale
     };
 
     calendars_object.as_object().for_each_member([&](auto const& calendar_name, JsonValue const& value) {
+        // The generic calendar is not a supported Unicode calendar key, so skip it:
+        // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale/calendar#unicode_calendar_keys
+        if (calendar_name == "generic"sv)
+            return;
+
         auto& calendar = ensure_calendar(calendar_name);
 
         if (!locale_data.calendars.contains_slow(calendar_name))

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeLocale.cpp

@@ -407,12 +407,17 @@ static ErrorOr<void> parse_calendar_keywords(String locale_dates_path, UnicodeLo
         auto const& calendars_object = dates_object.as_object().get("calendars"sv);
 
         calendars_object.as_object().for_each_member([&](auto const& calendar_name, JsonValue const&) {
-            keyword_values.append(calendar_name);
+            // The generic calendar is not a supported Unicode calendar key, so skip it:
+            // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale/calendar#unicode_calendar_keys
+            if (calendar_name == "generic"sv)
+                return;
 
             // FIXME: Similar to the calendar aliases defined in GenerateUnicodeDateTimeFormat, this
             //        should be parsed from BCP47. https://unicode-org.atlassian.net/browse/CLDR-15158
             if (calendar_name == "gregorian"sv)
                 keyword_values.append("gregory"sv);
+            else
+                keyword_values.append(calendar_name);
         });
     }
 

Userland/Libraries/LibJS/Tests/builtins/Intl/DateTimeFormat/DateTimeFormat.prototype.resolvedOptions.js

@@ -21,32 +21,27 @@ describe("correct behavior", () => {
         const en = Intl.DateTimeFormat("en", { calendar: "gregory" });
         expect(en.resolvedOptions().calendar).toBe("gregory");
 
-        const el = Intl.DateTimeFormat("el", { calendar: "generic" });
-        expect(el.resolvedOptions().calendar).toBe("generic");
+        const el = Intl.DateTimeFormat("el", { calendar: "gregory" });
+        expect(el.resolvedOptions().calendar).toBe("gregory");
     });
 
     test("calendar may be set by locale extension", () => {
         const en = Intl.DateTimeFormat("en-u-ca-gregory");
         expect(en.resolvedOptions().calendar).toBe("gregory");
 
-        const el = Intl.DateTimeFormat("el-u-ca-generic");
-        expect(el.resolvedOptions().calendar).toBe("generic");
+        const el = Intl.DateTimeFormat("el-u-ca-gregory");
+        expect(el.resolvedOptions().calendar).toBe("gregory");
     });
 
     test("calendar option overrides locale extension", () => {
-        const el = Intl.DateTimeFormat("el-u-ca-generic", { calendar: "gregory" });
+        const el = Intl.DateTimeFormat("el-u-ca-gregory", { calendar: "gregory" });
         expect(el.resolvedOptions().calendar).toBe("gregory");
     });
 
     test("calendar option limited to known 'ca' values", () => {
-        ["generic", "hello"].forEach(calendar => {
+        ["gregory", "hello"].forEach(calendar => {
             const en = Intl.DateTimeFormat("en", { calendar: calendar });
-            expect(en.resolvedOptions().calendar).toBe("generic");
-        });
-
-        ["generic", "hello"].forEach(calendar => {
-            const en = Intl.DateTimeFormat(`en-u-ca-${calendar}`);
-            expect(en.resolvedOptions().calendar).toBe("generic");
+            expect(en.resolvedOptions().calendar).toBe("gregory");
         });
     });