Check against tag emoji for user input in actuallyNonEmptyStringOrNull

app/utils/zod.test.ts

@@ -1,5 +1,9 @@
 import { describe, expect, it } from "vitest";
-import { hasZalgo, normalizeFriendCode } from "./zod";
+import {
+	actuallyNonEmptyStringOrNull,
+	hasZalgo,
+	normalizeFriendCode,
+} from "./zod";
 
 describe("normalizeFriendCode", () => {
 	it("returns well formatted friend code as is", () => {
@@ -40,3 +44,36 @@ describe("hasZalgo", () => {
 		expect(hasZalgo("こんにちは")).toBe(false);
 	});
 });
+
+describe("actuallyNonEmptyStringOrNull", () => {
+	it("returns null for an empty string", () => {
+		expect(actuallyNonEmptyStringOrNull("")).toBeNull();
+	});
+
+	it("returns null for a string with only spaces", () => {
+		expect(actuallyNonEmptyStringOrNull("    ")).toBeNull();
+	});
+
+	it("returns trimmed string for a string with visible characters and spaces", () => {
+		expect(actuallyNonEmptyStringOrNull("  hello world  ")).toBe("hello world");
+	});
+
+	it("removes invisible characters and trims", () => {
+		expect(actuallyNonEmptyStringOrNull("​​​​test​​​​")).toBe("test");
+	});
+
+	it("returns original value if not a string", () => {
+		expect(actuallyNonEmptyStringOrNull(123)).toBe(123);
+		expect(actuallyNonEmptyStringOrNull(null)).toBe(null);
+		expect(actuallyNonEmptyStringOrNull(undefined)).toBe(undefined);
+		expect(actuallyNonEmptyStringOrNull({})).toEqual({});
+	});
+
+	it("returns null for a string with only zero width spaces", () => {
+		expect(actuallyNonEmptyStringOrNull("​​​​​​​​​​")).toBeNull();
+	});
+
+	it("returns null for a string with only tag space emoji", () => {
+		expect(actuallyNonEmptyStringOrNull("󠀠󠀠󠀠󠀠󠀠")).toBeNull();
+	});
+});

app/utils/zod.ts

@@ -148,7 +148,7 @@ export function safeJSONParse(value: unknown): unknown {
 	}
 }
 
-const EMPTY_CHARACTERS = ["\u200B", "\u200C", "\u200D", "\u200E", "\u200F"];
+const EMPTY_CHARACTERS = ["\u200B", "\u200C", "\u200D", "\u200E", "\u200F", "󠀠"];
 const EMPTY_CHARACTERS_REGEX = new RegExp(EMPTY_CHARACTERS.join("|"), "g");
 
 const zalgoRe = /%CC%/g;
@@ -197,7 +197,7 @@ export const safeNullableStringSchema = ({
 /**
  * Processes the input value and returns a non-empty string with invisible characters cleaned out or null.
  */
-function actuallyNonEmptyStringOrNull(value: unknown) {
+export function actuallyNonEmptyStringOrNull(value: unknown) {
 	if (typeof value !== "string") return value;
 
 	const trimmed = value.replace(EMPTY_CHARACTERS_REGEX, "").trim();