public void FileBuilderShouldBuildFileObjectWithExpectedProperties() { var ioMock = new Mock <IDiskIOWrapper>(); ioMock.Setup(mock => mock.ReadAllLinesFromFile(FilePath)) .Returns(FileContent); var result = FileBuilder.BuildFileFromPath(FilePath, ioMock.Object); result.Extension.Should() .Be(".ext"); result.Filename.Should() .Be("somefile.ext"); result.Path.Should() .Be(Path.Join("C:", "somedir", "somesubdir")); result.Content[0] .Text.Should() .Be("first line"); result.Content[1] .Text.Should() .Be("second line"); }