AssertContents asserts the contents of a file.

AssertExists asserts if a path exists.

AssertNotExists asserts a path does exist.

AssertOutput asserts the output matches the actual contents.

ReadTestData reads a file from `testdata` and returns it as a string.

StageDir stages a directory on the provided filesystem from testdata.

StageFile stages a file on on the provided filesystem from testdata.

WithApp runs an enclosure with a mocked app and fs.

WithAppFs runs an enclosure with a mocked app and fs.