cli: Shows message for no meshes (#4738)

Shows message if no mesh exits in the cluster.
Fixes #4697

Signed-off-by: mudit singh <[email protected]>

Author: mudit-01

cmd/cli/version.go

@@ -170,6 +170,9 @@ func (r *remoteVersion) proxyGetMeshVersion(pod string, namespace string, client
 }
 
 func (v *versionCmd) outputPrettyVersionInfo(remoteVerList []*remoteVersionInfo) string {
+	if len(remoteVerList) == 0 {
+		return "Unable to find OSM control plane in the cluster\n"
+	}
 	table := "\nMESH NAME\tMESH NAMESPACE\tVERSION\tGIT COMMIT\tBUILD DATE\n"
 	for _, remoteVersionInfo := range remoteVerList {
 		if remoteVersionInfo != nil && remoteVersionInfo.meshName != "" {

cmd/cli/version_test.go

@@ -216,8 +216,8 @@ func TestOutputPrettyVersionInfo(t *testing.T) {
 		},
 		{
 			name:                  "mesh versions with no remote version info",
-			remoteVersionInfoList: nil,
-			expected:              "\nMESH NAME\tMESH NAMESPACE\tVERSION\tGIT COMMIT\tBUILD DATE\n",
+			remoteVersionInfoList: []*remoteVersionInfo{},
+			expected:              "Unable to find OSM control plane in the cluster\n",
 		},
 	}