refactor: refacotr preference

packages/@vben-core/shared/toolkit/src/index.ts

@@ -3,6 +3,7 @@ export * from './date';
 export * from './diff';
 export * from './hash';
 export * from './inference';
+export * from './letter';
 export * from './merge';
 export * from './namespace';
 export * from './nprogress';

packages/@vben-core/shared/toolkit/src/letter.test.ts

@@ -0,0 +1,55 @@
+import { describe, expect, it } from 'vitest';
+
+import { capitalizeFirstLetter, toLowerCaseFirstLetter } from './letter';
+
+// 编写测试用例
+describe('capitalizeFirstLetter', () => {
+  it('should capitalize the first letter of a string', () => {
+    expect(capitalizeFirstLetter('hello')).toBe('Hello');
+    expect(capitalizeFirstLetter('world')).toBe('World');
+  });
+
+  it('should handle empty strings', () => {
+    expect(capitalizeFirstLetter('')).toBe('');
+  });
+
+  it('should handle single character strings', () => {
+    expect(capitalizeFirstLetter('a')).toBe('A');
+    expect(capitalizeFirstLetter('b')).toBe('B');
+  });
+
+  it('should not change the case of other characters', () => {
+    expect(capitalizeFirstLetter('hElLo')).toBe('HElLo');
+  });
+});
+
+describe('toLowerCaseFirstLetter', () => {
+  it('should convert the first letter to lowercase', () => {
+    expect(toLowerCaseFirstLetter('CommonAppName')).toBe('commonAppName');
+    expect(toLowerCaseFirstLetter('AnotherKeyExample')).toBe(
+      'anotherKeyExample',
+    );
+  });
+
+  it('should return the same string if the first letter is already lowercase', () => {
+    expect(toLowerCaseFirstLetter('alreadyLowerCase')).toBe('alreadyLowerCase');
+  });
+
+  it('should handle empty strings', () => {
+    expect(toLowerCaseFirstLetter('')).toBe('');
+  });
+
+  it('should handle single character strings', () => {
+    expect(toLowerCaseFirstLetter('A')).toBe('a');
+    expect(toLowerCaseFirstLetter('a')).toBe('a');
+  });
+
+  it('should handle strings with only one uppercase letter', () => {
+    expect(toLowerCaseFirstLetter('A')).toBe('a');
+  });
+
+  it('should handle strings with special characters', () => {
+    expect(toLowerCaseFirstLetter('!Special')).toBe('!Special');
+    expect(toLowerCaseFirstLetter('123Number')).toBe('123Number');
+  });
+});

packages/@vben-core/shared/toolkit/src/letter.ts

@@ -0,0 +1,20 @@
+/**
+ * 将字符串的首字母大写
+ * @param string
+ */
+function capitalizeFirstLetter(string: string): string {
+  return string.charAt(0).toUpperCase() + string.slice(1);
+}
+
+/**
+ * 将字符串的首字母转换为小写。
+ *
+ * @param str 要转换的字符串
+ * @returns 首字母小写的字符串
+ */
+function toLowerCaseFirstLetter(str: string): string {
+  if (!str) return str; // 如果字符串为空，直接返回
+  return str.charAt(0).toLowerCase() + str.slice(1);
+}
+
+export { capitalizeFirstLetter, toLowerCaseFirstLetter };