testing: fmt.Print missing a trailing newline interferes with test output formatting #35845
Description
What version of Go are you using (go version)?
$ go version go version go1.13 darwin/amd64
Does this issue reproduce with the latest release?
Yes
What operating system and processor architecture are you using (go env)?
go env Output
$ go env GO111MODULE="on" GOARCH="amd64" GOBIN="" GOCACHE="/Users/marcus.low/Library/Caches/go-build" GOENV="/Users/marcus.low/Library/Application Support/go/env" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="darwin" GONOPROXY="" GONOSUMDB="" GOOS="darwin" GOPATH="/Users/marcus.low/gopath" GOPRIVATE="" GOPROXY="direct" GOROOT="/usr/local/Cellar/go/1.13/libexec" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/local/Cellar/go/1.13/libexec/pkg/tool/darwin_amd64" GCCGO="gccgo" AR="ar" CC="clang" CXX="clang++" CGO_ENABLED="1" GOMOD="/Users/marcus.low/repositories/sandbox/go.mod" CGO_CFLAGS="-g -O2" CGO_CPPFLAGS="" CGO_CXXFLAGS="-g -O2" CGO_FFLAGS="-g -O2" CGO_LDFLAGS="-g -O2" PKG_CONFIG="pkg-config" GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/6y/t2pc26794j30sdnn4fx1lkzc0000gq/T/go-build987539708=/tmp/go-build -gno-record-gcc-switches -fno-common"
What did you do?
- Create a test file:
some_test.go
package somepkg
import (
"fmt"
"testing"
)
func TestBad(t *testing.T) {
fmt.Print("this is bad")
}
func TestOK(t *testing.T) {
fmt.Println("this is ok")
}
- Run the tests:
go test -json -v . | grep '"Action":"pass"'What did you expect to see?
3 lines of passes:
- pass event for
TestBad - pass event for
TestOK - pass event for the whole
somepkgpackage
What did you see instead?
pass event for TestBad is not emitted.
{"Time":"2019-11-26T17:17:07.640309+08:00","Action":"pass","Package":"sandbox/somepkg","Test":"TestOK","Elapsed":0}
{"Time":"2019-11-26T17:17:07.640327+08:00","Action":"pass","Package":"sandbox/somepkg","Elapsed":0}
However, the passing output line is included together with the fmt.Print output:
{"Time":"2019-11-26T17:19:24.851022+08:00","Action":"output","Package":"sandbox/somepkg","Test":"TestBad","Output":"this is bad--- PASS: TestBad (0.00s)\n"}