cmd/go: version command should error when given bad args
For example, 'go version -m' happily gives you Go's own version, even
though the -m flag only makes sense when grabbing the version of a
binary on disk.
Similarly, if any of the directly named files can't be found, the tool
would succeed. That's acceptable if an error is encountered while
walking a large directory, but not when locating a path directly given
by the user.
These added test cases run even in short mode, as 'go build' is not
needed for them.
Change-Id: I7bb40b72853799e31d9f86cc5e999c8d57813eef
Reviewed-on: https://go-review.googlesource.com/c/go/+/221397
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Bryan C. Mills <bcmills@google.com>