fileManager.createFileAtPath fails during unit tests - ios

Question

Currently I'm trying to create files during a unit test to see if I can retrieve the data after its created but the fileManager.createFileAtPath always fails. I looked at this post: fileManager.createFileAtPath always fails I implemented the solutions to that answer but it still fails. This is what the unit test and accompanying function looks like:
internal func getCacheFolderPath() -> String {
var folderPath = ""
guard let path = self.urls(for:.cachesDirectory , in: .userDomainMask).last?.path else {
return folderPath
}
folderPath = path + "/NetworkCache"
if !self.fileExists(atPath: folderPath) {
do {
try self.createDirectory(atPath: folderPath, withIntermediateDirectories: false, attributes: nil)
} catch {
print(error.localizedDescription)
}
}
return folderPath
}
func test_createFile(){
let path = sut?.getCacheFolderPath()
let fileManager = FileManager.default
if !FileManager.default.fileExists(atPath: path!) {
do {
try FileManager.default.createDirectory(atPath: path!, withIntermediateDirectories: true, attributes: nil)
} catch let error as NSError {
print(error.localizedDescription)
}
}
let isFileCreated = fileManager.createFile(atPath: path!, contents: mockData, attributes: nil)
print(isFileCreated)//This always returns false
}

Answer 1

Using the data.write(to:) instead of create file helped determine what the issue was. It looks like I was creating a folder as a file path and trying to save a file to that path. Since it was a file and not a folder it was returning that something already exists there.
Here is what the completed working code looks like:
func saveData(data: Data, forFileName fileName: String, completionHandler: #escaping (URL?)->()) {
let url = URL(fileURLWithPath: self.filePathForFileName(name: fileName))
print("saveData:\(url)")
do {
// [data writeToFile:[self thdncFilePathForFileName:name] atomically:YES];
try data.write(to: url, options: .atomic)
completionHandler(url)
} catch {
print(error.localizedDescription)
completionHandler(nil)
}
}
func test_createFile(){
var isSaved: Bool = false
let path = sut?.getCacheFolderPath()
let promise = expectation(description: "Completion Hander invoked")
if !FileManager.default.fileExists(atPath: path!)
{
do {
try FileManager.default.createDirectory(atPath: path!, withIntermediateDirectories: true, attributes: nil)
} catch let error as NSError {
print(error.localizedDescription)
}
}
sut?.saveData(data: mockData!, forFileName: filePath, completionHandler: { (url) in
let fileManager = MockFileManager.default
if fileManager.fileExists(atPath: self.sut!.filePathForFileName(name: self.filePath)) {
isSaved = true
print("FILE AVAILABLE")
} else {
isSaved = false
print("FILE NOT AVAILABLE")
}
promise.fulfill()
})
wait(for: [promise], timeout: 10, enforceOrder: true)
XCTAssertTrue(isSaved)
}