So I understand this method gives a format that htmlFileDiff can handle, but I'd prefer we didn't handle it that way. This method's purpose is to give a line-by-line diff of a file, something which doesn't really make sense for an image file. Instead of handling image files in here we should do it at a higher level where we construct the diff view model; if it's a file we want line by line diffs we use a FileDiffViewModel which uses /api/diff, if it's an image file we use ImageDiffViewModel that uses other endpoints to get the HEAD content of the file and the working directory content of the file