Maven——文件编译成功，但测试失败是什么原因？

这是测试用例的内容
import org.junit.Test;
import org.junit.Assert;

public class DemoTest{
    @Test
    public void testSay(){
        Demo d = new Demo();
        String ret = d.say("maven");
        Assert.assertEquals("hello maven",ret);
    }    
}

报错提示
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile (default-testCompile) on project project-java: Compilation failure: Compilation failure:
[ERROR] /E:/project/project-java/src/test/java/com/111/DemoTest.java:[9,17] 找不到符号
[ERROR] 符号: 类 Demo
[ERROR] 位置: 类 come.111.DemoTest
[ERROR] /E:/project/project-java/src/test/java/com/111/DemoTest.java:[9,30] 找不到符号
[ERROR] 符号: 类 Demo
[ERROR] 位置: 类 come.111.DemoTest
[ERROR] -> [Help 1]

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project 
   xmlns="http://maven.apache.org/POM/4.0.0" 
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
   
   <modelVersion>4.0.0</modelVersion>

   <groupId>com.111</groupId>
   <artifactId>project-java</artifactId>
   <version>1.0</version>
   <packaging>jar</packaging>

   <dependencies>
      <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>4.12</version>
      </dependency>
   </dependencies>
</project>

版本
Apache Maven 3.6.3 (cecedd343002696d0abb50b32b541b8a6ba2883f)
Maven home: D:\Maven\apache-maven-3.6.3\bin..
Java version: 1.8.0_172, vendor: Oracle Corporation, runtime: C:\Program Files\Java\jdk1.8.0_172\jre
Default locale: zh_CN, platform encoding: GBK
OS name: "windows 10", version: "10.0", arch: "amd64", family: "windows"

破案了。。。结果是包名多写了一个字母

文件中没有添加Demo类的依赖，导致编译失败，测试失败。