added tty flag

shared/build/build.go

@@ -322,6 +322,7 @@ func (b *Builder) run() error {
 		AttachStdin:  false,
 		AttachStdout: true,
 		AttachStderr: true,
+		Tty:          script.DockerTty(b.Build.Docker),
 	}
 
 	// configure if Docker should run in privileged mode

shared/build/script/docker.go

@@ -43,7 +43,7 @@ func DockerHostname(d *Docker) string {
 
 // DockerTty returns true if the build
 // should allocate a pseudo tty
-func DockerTty(d *Docker) string {
+func DockerTty(d *Docker) bool {
 	if d == nil {
 		return false
 	}