[@wordpress/i18n] add new definitions (#35908)

* [@wordpress/i18n] add new definitions

* fix lint warnings

types/wordpress__i18n/index.d.ts

@@ -0,0 +1,87 @@
+// Type definitions for @wordpress/i18n 3.4
+// Project: https://github.com/WordPress/gutenberg/tree/master/packages/i18n/README.md
+// Definitions by: Derek Sifford <https://github.com/dsifford>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+/**
+ * Merges locale data into the Tannin instance by domain. Accepts data in a
+ * Jed-formatted JSON object shape.
+ *
+ * @see http://messageformat.github.io/Jed/
+ *
+ * @param data   Locale data configuration.
+ * @param domain Domain for which configuration applies.
+ */
+export function setLocaleData(data: any, domain?: string): void;
+
+/**
+ * Retrieve the translation of text.
+ *
+ * @see https://developer.wordpress.org/reference/functions/__/
+ *
+ * @param  text   Text to translate.
+ * @param  domain Domain to retrieve the translated text.
+ */
+export function __(text: string, domain?: string): string;
+
+/**
+ * Retrieve translated string with gettext context.
+ *
+ * @see https://developer.wordpress.org/reference/functions/_x/
+ *
+ * @param  text    Text to translate.
+ * @param  context Context information for the translators.
+ * @param  domain  Domain to retrieve the translated text.
+ */
+export function _x(text: string, context: string, domain?: string): string;
+
+/**
+ * Translates and retrieves the singular or plural form based on the supplied
+ * number.
+ *
+ * @see https://developer.wordpress.org/reference/functions/_n/
+ *
+ * @param  single The text to be used if the number is singular.
+ * @param  plural The text to be used if the number is plural.
+ * @param  number The number to compare against to use either the
+ *                         singular or plural form.
+ * @param  domain Domain to retrieve the translated text.
+ */
+export function _n(
+    single: string,
+    plural: string,
+    n: number,
+    domain?: string
+): string;
+
+/**
+ * Translates and retrieves the singular or plural form based on the supplied
+ * number, with gettext context.
+ *
+ * @see https://developer.wordpress.org/reference/functions/_nx/
+ *
+ * @param  single  The text to be used if the number is singular.
+ * @param  plural  The text to be used if the number is plural.
+ * @param  number  The number to compare against to use either the
+ *                          singular or plural form.
+ * @param  context Context information for the translators.
+ * @param  domain  Domain to retrieve the translated text.
+ */
+export function _nx(
+    single: string,
+    plural: string,
+    n: number,
+    context: string,
+    domain?: string
+): string;
+
+/**
+ * Returns a formatted string. If an error occurs in applying the format, the
+ * original format string is returned.
+ *
+ * @param  format  The format of the string to generate.
+ * @param  args Arguments to apply to the format.
+ *
+ * @see http://www.diveintojavascript.com/projects/javascript-sprintf
+ */
+export function sprintf(format: string, ...args: any[]): string;

types/wordpress__i18n/tsconfig.json

@@ -0,0 +1,19 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": ["es6"],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": ["../"],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true,
+        "paths": {
+            "@wordpress/i18n": ["wordpress__i18n"]
+        }
+    },
+    "files": ["index.d.ts", "wordpress__i18n-tests.ts"]
+}

types/wordpress__i18n/tslint.json

@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }

types/wordpress__i18n/wordpress__i18n-tests.ts

@@ -0,0 +1,4 @@
+import * as i18n from "@wordpress/i18n";
+
+i18n.sprintf(i18n._n("%d hat", "%d hats", 4, "text-domain"), 4); // 4 hats
+i18n.__("foobar", "foo-bar");