Complete runtime API implementation

test/login/he.ts

@@ -0,0 +1,7 @@
+import type { MessageKey_defaultSet } from "keycloakify/login/i18n";
+
+/* spell-checker: disable */
+const messages: Record<MessageKey_defaultSet, string> = null as any;
+/* spell-checker: enable */
+
+export default messages;

test/login/i18n.typelevel-spec.ts

@@ -0,0 +1,54 @@
+import { i18nInitializer } from "keycloakify/login/i18n";
+import { assert, type Equals } from "tsafe/assert";
+import { Reflect } from "tsafe/Reflect";
+
+const { useI18n, ofTypeI18n } = i18nInitializer
+    .withThemeName<"my-theme-1" | "my-theme-2">()
+    .withExtraLanguages({
+        he: () => import("./he")
+    })
+    .withCustomTranslations({
+        en: {
+            myCustomKey1: "my-custom-key-1-en",
+            myCustomKey2: {
+                "my-theme-1": "my-theme-1-en",
+                "my-theme-2": "my-theme-2-en"
+            }
+        },
+        he: {
+            myCustomKey1: "my-custom-key-1-he",
+            myCustomKey2: {
+                "my-theme-1": "my-theme-1-xx",
+                "my-theme-2": "my-theme-2-xx"
+            }
+        }
+    })
+    .create();
+
+type I18n = typeof ofTypeI18n;
+
+{
+    const { i18n } = useI18n({ kcContext: Reflect<any>() });
+
+    assert<Equals<typeof i18n, I18n>>;
+}
+
+{
+    const i18n = Reflect<I18n>();
+
+    const got = i18n.currentLanguageTag;
+
+    type Expected =
+        | import("keycloakify/login/i18n/messages_defaultSet/types").LanguageTag
+        | "he";
+
+    assert<Equals<typeof got, Expected>>;
+}
+
+{
+    const i18n = Reflect<I18n>();
+
+    const node = i18n.msg("myCustomKey2");
+
+    assert<Equals<typeof node, JSX.Element>>;
+}