Swift单元测试，如果方法可以处理可选设置为nil

Question

This applies to a project with both ObjC and Swift, where the code I relate to is written and tested in Swift.

I have a communicator class which receives a document object and from that object should retrieve a documentId. My communicator has a serverPathForDocument: method, which uses this documentId to build a remote path to fetch relevant data.

Writing unit tests for the communicator I realised I wanted to know if my serverPathForDocument: method can handle a non-initiated (nil) value on the documentId. If written in Obj-C my test would look something like:

- (void)testThatRemotePathForDocumentCanHandleNilDocumentId {
   testDocument.documentId = nil
   XCTAssertNoThrow([sut serverPathForDocument: testDocument], "Method should handle nil argument");
}

Swift doesn't have exception, or so I've read, so how would I write a proper unit test that checks if a method can handle an optional set to nil?

Answer 1

I would probably want the serverPathForDocument method to return an optional path object (whatever it means for you). It would then be the responsibility of the caller to make sure the optional isn't nil and really represents a path.