Disabled Mock Triggers NPE when Checking isMock #3469
Description
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There is the ability to trigger a NullPointerException by calling isMock on a disabled mock. This behavior should probably be changed to either return true, because a DisabledMock is still a mock or isMock should throw a DisabledMockException because you are interacting with a disabledMock.
Problematic Code is: DisabledMockHandler#getMockSettings returning null here breaks the logic for determining if an object a mock.
@Override
public MockCreationSettings getMockSettings() {
return null;
}
NPE Source is in the following loop of MockUtil#getMockHandlerOrNull.
for (MockMaker mockMaker : mockMakers.values()) {
MockHandler<?> handler = mockMaker.getHandler(mock);
if (handler != null) {
assert getMockMaker(handler.getMockSettings().getMockMaker()) == mockMaker;
return handler;
}
}
Stack Trace Snippet:
java.lang.NullPointerException: Cannot invoke "org.mockito.mock.MockCreationSettings.getMockMaker()" because the return value of "org.mockito.invocation.MockHandler.getMockSettings()" is null
at org.mockito.internal.util.MockUtil.getMockHandlerOrNull(MockUtil.java:160)
at org.mockito.internal.util.MockUtil.isMock(MockUtil.java:147)
at org.mockito.internal.util.DefaultMockingDetails.isMock(DefaultMockingDetails.java:32)
at org.mockito.internal.framework.DefaultMockitoFrameworkTest.behavior_after_clear_inline_mocks_is_mock(DefaultMockitoFrameworkTest.java:226)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:569)
The following unit test reproduces the issue. This unit test can be added to DefaultMockitoFrameworkTest and will fail for an NPE. This test should probably be modeled to either trigger a DisabledMockException or return true because a DisabledMock is still a mock.
@Test
public void behavior_after_clear_inline_mocks_is_mock() {
// clearing mocks only works with inline mocking
assumeTrue(Plugins.getMockMaker() instanceof InlineMockMaker);
PersonWithName obj = mock(PersonWithName.class);
when(obj.getMyName()).thenReturn("Bob");
assertEquals("Bob", obj.getMyName());
assertTrue(mockingDetails(obj).isMock());
framework.clearInlineMocks();
try {
mockingDetails(obj).isMock();
} catch (DisabledMockException e) {
return;
}
Assert.fail("Should have thrown DisabledMockException");
}