In these tests, if I understand correctly, we don't test well the existence of components:
tests/jest/views/function/FunctionDefinition.test.js 50: expect( wrapper.findComponent( FunctionDefinitionName ) ).toBeTruthy(); 51: expect( wrapper.findComponent( FunctionDefinitionAliases ) ).toBeTruthy(); 52: expect( wrapper.findComponent( FunctionDefinitionInputs ) ).toBeTruthy(); 53: expect( wrapper.findComponent( FunctionDefinitionOutput ) ).toBeTruthy(); 54: expect( wrapper.findComponent( FunctionDefinitionFooter ) ).toBeTruthy(); tests/jest/views/function/viewer/FunctionViewerAboutNames.test.js 40: expect( wrapper.findComponent( FunctionViewerSidebar ) ).toBeTruthy(); tests/jest/views/function/definition/FunctionDefinitionFooter.test.js 56: expect( wrapper.findComponent( DialogContainer ) ).toBeTruthy(); tests/jest/views/function/viewer/FunctionViewerAboutExamples.test.js 52: expect( wrapper.findComponent( TableComponent ) ).toBeTruthy(); tests/jest/views/function/viewer/FunctionViewerAboutAliases.test.js 40: expect( wrapper.findComponent( FunctionViewerSidebar ) ).toBeTruthy();
findComponent just returns a new wrapper, which may not hold anything. When we remove the corresponding component from the tested modules, the tests continue to pass (I checked that with FunctionDefinition.test.js).
If we want to check the existence of components, we also rather call .exists(). An example of a well written test (I checked that it gives a true positive and fails when we remove the component): https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/WikiLambda/+/9cc8307777d1cf85783d0ff09d916146bac1e191/tests/jest/views/function/FunctionDetails.test.js#103
However, when I attempt to add a .exists() to the false positive tests, the test fails.