PowerMockito的模拟文件

Question

我有以下测试代码：

@RunWith(PowerMockRunner.class)
@PrepareForTest({Logger.class, Files.class})
public class TestClass {
  private static final List<String> LIST = new ArrayList<String>() {{
    add("some entry");
  }};
  private static final Path PATH = Paths.get("/tmp/foo");
  @Before
  public void setup() {
    PowerMockito.spy(Files.class);
    PowerMockito.doReturn(LIST).when(Files.class, "readAllLines", PATH, Charset.defaultCharset());
  }
  @Test
  public void test() {}
}

上面的代码在最后一行抛出一个"NoSuchFileException"。这是堆叠竞赛：

java.nio.file.NoSuchFileException：/tmp/foosun.nio.fs.UnixException.translateToIOException（UnixExcession.java:86）在sun.nio.fs.UnixException.rethrowAsIOException（UnixException.java：102）在sun.nio.fs.UnixException.rethrowAsIOException（UnixException.java：107）在sun.nio.fs.UnixFileSystemProvider.newByteChannel（UnixFileSystem Provider.java:214）位于java.nio.file.Files.newByteChannel（Files.java:317）java.nio.file.Files.newByteChannel（Files.java:363）位于java.nio.file.spi.FileSystemProvider.newInputStream（FileSystemProvider.java:380）位于java.nio.file.Files.newInputStream（Files.java:108）java.nio.file.Files.newBufferedReader（Files.java:2677）位于java.nio.file.Files.readAllLines（Files.java:3033）位于位于的sun.reflect.NativeMethodAccessorImpl.invoke0（本机方法）sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:57）在sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）在java.lang.reflect.Method.ioke（Method.java:606）org.powermock.reflect.internal.WhiteboxImpl.performMethodInvocation（WhiteboxImpl.java:2014）在org.powermock.reflect.internal.WhiteboxImpl.doInvokeMethod（WhiteboxImpl.java:885）在org.powermock.reflect.internal.WhiteboxImpl.invokeMethod（WhiteboxImpl.java:859）网址：org.powermock.reflect.Whitebox.invokeMethod（Whitebox.java:466）org.powermock.api.mokito.internal.expection.PowerMockitoStubberImpl.when（PowerMockitoStubberImpl.java:106）在TestClass.setup（TestClass.java:29）位于的sun.reflect.NativeMethodAccessorImpl.invoke0（本机方法）sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:57）在sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）在java.lang.reflect.Method.ioke（Method.java:606）org.junit.internal.runners.MethodRoadie.runBefores（MethodRoadie.java:129）在org.junit.internal.runners.MethodRoadie.runBeforestThenAfters（MethodRoadie.java:93）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest在org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper（PowerMockjunit47Runner Delegateimpl.java:127）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest（PowerMockJunit47Runner Delegateimpl.java:82）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters（PowerMockjunit44Runner Delegateimpl.java:282）在org.junit.internal.runners.MethodRoadie.runTest（MethodRoadie.java:84）网址：org.junit.internal.runners.MethodRoadie.run（MethodRoadie.java:49）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods（PowerMockjunit44Runner Delegateimpl.java:146）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run（PowerMockjunit44Runner Delegateimpl.java:120）在org.junit.internal.runners.ClassRoadie.runUnprotected（ClassRoadie.java:34）在org.junit.internal.runners.ClassRoadie.runProtected（ClassRoadie.java:44）在org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run（PowerMockjunit44Runner Delegateimpl.java:118）在org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run（JUnit4Test SuiteChuckerImpl.java:101）在org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run（AbstractCommonPower-MockRunner.java:53）在org.powermock.modules.junit4.PowerMockRunner.run（PowerMockRuner.java:53）在org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run（JUnit4TtestReference.java:50）在org.eclipse.jdt.internal.junit.runner.TestExecution.run（TestExecution.java:38）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:467）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:683）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run（RemoteTestRunner.java:390）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main（RemoteTestRunner.java:197）

我不太明白我在这里做错了什么。

Answer 1

我发现了问题：问题是Files是System类。

https://github.com/powermock/powermock/wiki/mocksystem