cmd/go: -failfast flag does not apply across packages

[dsnet]

Using go1.12

The documentation for failfast says "Do not start new tests after the first test failure."

When running go test ./... -failfast and one of the packages has a failure, it continues to run the tests for other packages. My interpretation of the documentation above is that go test would stop after any failure, even if in a different package.

[dmitshur]

/cc @jayconrod @bcmills

[zenovich]

For now, this command helps me a lot:

for s in $(go list ./...); do if ! go test -failfast -v -p 1 $s; then break; fi; done

[lookfirst]

Bump?

[docmerlin]

Bump!