当用于使用静态方法调用测试 Java 类时，GroovyMock 不起作用

Question

当静态类在其他 Java 类中使用时，Groovy 测试不会为静态类创建模拟。下面是证明这一点的代码sn-p

被测Java类：

public class JavaClass {
    public void method() { 
      ClassWithStaticMethod.doSomething();
    }
}

带有静态方法的Java类：

public class ClassWithStaticMethod { 
    public static void doSomething() {
        System.out.println("Static method called");
    } 
}

Groovy 测试失败：

class JavaClassTest extends Specification {
  def 'test'() {
    given:
    GroovyMock(ClassWithStaticMethod, global: true)
    JavaClass javaClass = new JavaClass()

    when:
    javaClass.method()

    then:
    1 * ClassWithStaticMethod.doSomething() // <--- FAILS
  }
}

这会失败并显示消息：

Static method called <--- original method is called, it's not mocked

Too few invocations for:

1 * ClassWithStaticMethod.doSomething()   (0 invocations)

Unmatched invocations (ordered by similarity):

None

因此，不会模拟静态方法，而是始终调用实际的实现。谁能解释这种行为？知道如何绕过这个吗？

Java 版本：1.7.0_79，Groovy 版本：2.4.7，Spock 版本：1.0-groovy-2.4，cgclib：3.1

Answer 1

如果java代码是用groovyc编译的

    def "foo"() {
      setup:
        // GroovyMock(ClassWithStaticMethod, global: true)
        GroovySpy(ClassWithStaticMethod, global: true)
        JavaClass javaClass = new JavaClass()

      when:
        javaClass.method()

      then:
        // 1 * ClassWithStaticMethod.doSomething()
        1 * ClassWithStaticMethod.doSomething() >> null
    }

如果java代码是用javac编译的

1.准备测试代码（这个示例是MySpock.groovy）

// This Grabs are used for compile.
// These libraries must specifiy on class path when the file executs.
@Grapes([
  @Grab(group='org.jmockit', module='jmockit', version='1.8'),
  @Grab(group='org.spockframework', module='spock-core', version='1.0-groovy-2.4')
])

import spock.lang.*
import mockit.*

class MySpock extends Specification {

  def "hoge"() {
    setup:

    // Overwrite ClassWithStaticMethod#doSomething(static method) with JMockit/MockUp
    new MockUp<ClassWithStaticMethod>() {
      @Mock
      public static void doSomething() {
        Logger.append("abc")
      }

    }

    // Target object for this test
    JavaClass javaClass = new JavaClass()

    when: "Execute target method"
    javaClass.method()

    then: "ClassWithStaticMethod#doSomething was mocked and write the value in a file"
    Logger.count() == 1

    cleanup: "Delete log file for this test"
    Logger.delete()
  }
}

// Logging Utility for only this test.
class Logger {
  static logFile = new File("/tmp/MySpock.groovy.log")
  static append = {String msg -> logFile.append("${msg}${System.getProperty("line.separator")}")}
  static count = {logFile.readLines()?.size()?:0}
  static delete = { logFile.delete() }
}

2.编译代码

javac ClassWithStaticMethod.java&&javac JavaClass.java&&groovyc MySpock.groovy

3.执行测试

groovy -cp .:$HOME/.groovy/grapes/org.jmockit/jmockit/jars/jmockit-1.8.jar:$HOME/.groovy/grapes/org.spockframework/spock-core/jars/spock-core-1.0-groovy-2.4.jar MySpock

我第一次使用 JMockit。
所以，我不知道这种用法是否正确。
我不知道在 Spock 和 Mock(JMockit) 之间访问和添加静态字段的方法。
因此我创建了日志文件来检查是否从“JavaClass#method”调用了“ClassWithStaticMethod#doSomething”。