Add easterEggUtil with generateHappy() function (fix color CSS bug)

package.json

@@ -79,6 +79,11 @@
       "types": "./dist/types/deviceUtil/index.d.ts",
       "require": "./dist/types/deviceUtil/index.js",
       "import": "./dist/types/deviceUtil/index.js"
+    },
+    "./easterEggUtil": {
+      "types": "./dist/types/easterEggUtil/index.d.ts",
+      "require": "./dist/types/easterEggUtil/index.js",
+      "import": "./dist/types/easterEggUtil/index.js"
     }
   },
   "scripts": {

package/easterEggUtil/generateHappy/index.test.ts

@@ -0,0 +1,79 @@
+import { describe, test, expect, vi, beforeEach, afterEach } from "vitest";
+import generateHappy from ".";
+
+describe("generateHappy", () => {
+  let consoleLogSpy: ReturnType<typeof vi.spyOn>;
+
+  beforeEach(() => {
+    // console.log를 spy로 대체하여 호출 여부를 추적합니다.
+    consoleLogSpy = vi.spyOn(console, "log").mockImplementation(() => {});
+  });
+
+  afterEach(() => {
+    // 각 테스트 후 spy를 복원합니다.
+    consoleLogSpy.mockRestore();
+  });
+
+  test("사용자 정의 메시지가 없을 때 기본 메시지 중 하나를 반환해야 한다", () => {
+    const result = generateHappy();
+
+    const defaultMessages = [
+      "Keep going — you're doing great! 💪",
+      "Small steps lead to big changes. 🌱",
+      "Today is a good day to smile. 😊",
+      "You're closer than you think. 🌈",
+      "Stay curious, stay kind. ✨",
+      "Progress, not perfection. 🚀",
+      "You make the code better. 💻❤️",
+      "Breathe. You're doing your best. 🌤️",
+      "Trust the process, enjoy the journey. 🛤️",
+      "Every bug fixed is a victory. 🐞🏆",
+    ];
+
+    expect(defaultMessages).toContain(result);
+  });
+
+  test("사용자 정의 메시지를 전달하면 해당 메시지를 반환해야 한다", () => {
+    const customMessage = "Custom happy message!";
+    const result = generateHappy(customMessage);
+
+    expect(result).toBe(customMessage);
+  });
+
+  test("console.log가 호출되어야 한다", () => {
+    generateHappy("Test message");
+
+    expect(consoleLogSpy).toHaveBeenCalledTimes(1);
+  });
+
+  test("console.log에 타임스탬프와 메시지가 포함되어야 한다", () => {
+    const testMessage = "Test message";
+    generateHappy(testMessage);
+
+    expect(consoleLogSpy).toHaveBeenCalled();
+    const [firstArg] = consoleLogSpy.mock.calls[0];
+
+    // 첫 번째 인자에 타임스탬프와 메시지가 포함되어 있는지 확인
+    expect(firstArg).toContain(testMessage);
+    expect(firstArg).toMatch(/\[\d{1,2}:\d{2}:\d{2}.*\]/); // 타임스탬프 형식 확인
+  });
+
+  test("console.log에 올바른 스타일이 적용되어야 한다", () => {
+    generateHappy("Test message");
+
+    expect(consoleLogSpy).toHaveBeenCalled();
+    const args = consoleLogSpy.mock.calls[0];
+
+    // 스타일 인자들이 올바르게 전달되었는지 확인
+    expect(args[1]).toBe('color: #ff69b4; font-weight: bold;');
+    expect(args[2]).toBe('color: #333; font-size: 14px;');
+  });
+
+  test("여러 번 호출해도 정상적으로 동작해야 한다", () => {
+    generateHappy("Message 1");
+    generateHappy("Message 2");
+    generateHappy();
+
+    expect(consoleLogSpy).toHaveBeenCalledTimes(3);
+  });
+});

package/easterEggUtil/generateHappy/index.ts

@@ -0,0 +1,32 @@
+/**
+ * 개발자에게 격려 메시지를 콘솔에 출력하는 함수입니다.
+ * @param message 출력할 사용자 정의 메시지 (선택 사항)
+ * @returns {string} 출력된 메시지 텍스트
+ */
+export default function generateHappy(message?: string) {
+  const defaultMessages = [
+    "Keep going — you're doing great! 💪",
+    "Small steps lead to big changes. 🌱",
+    "Today is a good day to smile. 😊",
+    "You're closer than you think. 🌈",
+    "Stay curious, stay kind. ✨",
+    "Progress, not perfection. 🚀",
+    "You make the code better. 💻❤️",
+    "Breathe. You're doing your best. 🌤️",
+    "Trust the process, enjoy the journey. 🛤️",
+    "Every bug fixed is a victory. 🐞🏆",
+  ];
+
+  const text =
+    message ??
+    defaultMessages[Math.floor(Math.random() * defaultMessages.length)];
+  const timestamp = new Date().toLocaleTimeString();
+
+  console.log(
+    `%c[${timestamp}] %c${text}`,
+    'color: #ff69b4; font-weight: bold;',
+    'color: #333; font-size: 14px;'
+  );
+
+  return text;
+}

package/easterEggUtil/index.ts

@@ -0,0 +1 @@
+export { default as generateHappy } from "./generateHappy";

package/index.ts

@@ -9,6 +9,7 @@ export * as searchQueryUtil from "./searchQueryUtil";
 export * as typeUtil from "./typeUtil";
 export * as formatUtil from "./formatUtil";
 export * as deviceUtil from "./deviceUtil";
+export * as easterEggUtil from "./easterEggUtil";
 
 // 개별 함수에 대한 익스포트 진행
 export * from "./stringUtil";
@@ -21,3 +22,4 @@ export * from "./searchQueryUtil";
 export * from "./typeUtil";
 export * from "./formatUtil";
 export * from "./deviceUtil";
+export * from "./easterEggUtil";