修复那些不是很驼但又想驼的命名.

https://gitee.com/baomidou/mybatis-plus/issues/I1VZUR

mybatis-plus-generator/src/main/java/com/baomidou/mybatisplus/generator/config/rules/NamingStrategy.java

@@ -58,7 +58,7 @@ public enum NamingStrategy {
         Arrays.stream(camels).filter(camel -> !StringUtils.isBlank(camel)).forEach(camel -> {
             if (result.length() == 0) {
                 // 第一个驼峰片段，全部字母都小写
-                result.append(camel);
+                result.append(camel.toLowerCase());
             } else {
                 // 其他的驼峰片段，首字母大写
                 result.append(capitalFirst(camel));

mybatis-plus-generator/src/test/java/com/baomidou/mybatisplus/generator/config/rules/NamingStrategyTest.java

@@ -14,5 +14,14 @@ public class NamingStrategyTest {
         Assertions.assertEquals(NamingStrategy.removePrefix("test_ab", new HashSet<>(Arrays.asList("t_", "test"))), "_ab");
     }
 
+    @Test
+    void underlineToCamelTest(){
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("Aid"), "aid");
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("test_id"), "testId");
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("TEST_ID"), "testId");
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("Test_id"), "testId");
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("Test_ID"), "testId");
+        Assertions.assertEquals(NamingStrategy.underlineToCamel("TeSt_id"), "testId");
+    }
 
 }