Refactor parsing to not require --remote to be first

Use cobra.Command.FParseErrWhitelist to no longer require --remote to be
the first argument in flags when using CLI

Signed-off-by: Jhon Honce <jhonce@redhat.com>

cmd/podman/registry/remote.go

@@ -5,22 +5,24 @@ import (
 	"sync"
 
 	"github.com/containers/podman/v2/pkg/domain/entities"
-	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
 )
 
-var (
-	// Was --remote given on command line
-	remoteOverride bool
-	remoteSync     sync.Once
-)
+// Value for --remote given on command line
+var remoteFromCLI = struct {
+	Value bool
+	sync  sync.Once
+}{}
 
-// IsRemote returns true if podman was built to run remote
+// IsRemote returns true if podman was built to run remote or --remote flag given on CLI
 // Use in init() functions as a initialization check
 func IsRemote() bool {
-	remoteSync.Do(func() {
-		remote := &cobra.Command{}
-		remote.Flags().BoolVarP(&remoteOverride, "remote", "r", false, "")
-		_ = remote.ParseFlags(os.Args)
+	remoteFromCLI.sync.Do(func() {
+		fs := pflag.NewFlagSet("remote", pflag.ContinueOnError)
+		fs.BoolVarP(&remoteFromCLI.Value, "remote", "r", false, "")
+		fs.ParseErrorsWhitelist.UnknownFlags = true
+		fs.SetInterspersed(false)
+		_ = fs.Parse(os.Args[1:])
 	})
-	return podmanOptions.EngineMode == entities.TunnelMode || remoteOverride
+	return podmanOptions.EngineMode == entities.TunnelMode || remoteFromCLI.Value
 }

test/utils/utils.go

@@ -207,6 +207,10 @@ func WaitContainerReady(p PodmanTestCommon, id string, expStr string, timeout in
 
 // OutputToString formats session output to string
 func (s *PodmanSession) OutputToString() string {
+	if s == nil || s.Out == nil || s.Out.Contents() == nil {
+		return ""
+	}
+
 	fields := strings.Fields(string(s.Out.Contents()))
 	return strings.Join(fields, " ")
 }