Is the stat(...) call really necessary?

[JensRantil]

From what I understand, stat(...) is only used to check that a file exist. But really,

yamldiff/main.go

Lines 45 to 52 in 3a067f1

	yaml1, err := unmarshal(opts.File1)
	if err != nil {
	failOnErr(formatter, err)
	}
	yaml2, err := unmarshal(opts.File2)
	if err != nil {
	failOnErr(formatter, err)
	}

will fail if any of the files don't exist. Additionally, https://github.com/sahilm/yamldiff/blob/master/main.go#L80 will fail in other ways, such as read permissions being incorrect.

[sahilm]

I want to fail with a good error message.