"gofmt -d" should have non-zero exit if there is a diff

[belm0]

What version of Go are you using (go version)?

$ go version
go version go1.13.4 darwin/amd64

What did you do?

$ gofmt -d .
(... diff ...)
$ echo $?
0

What did you expect to see?

Exit value of 1, since there is a diff.

Presence of a diff is the error case, meaning that the code requires formatting. Then for example, makefile targets to check formatting can simply be "gofmt -d ." and do the right thing.

What did you see instead?

exit value of 0

[ALTree]

Hi,

this was requested in #24230 and #24427, and rejected. As noted in #24230, you can already check if gofmt -l is empty. Closing here as a dup of #24230.