test(cli): https rpc support

makes sure we dont have regression where HTTPS endpoint
starts getting cleartext requests

test/cli/cli_https_test.go

@@ -0,0 +1,46 @@
+package cli
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/ipfs/kubo/test/cli/harness"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCLIWithRemoteHTTPS(t *testing.T) {
+	tests := []struct{ addrSuffix string }{{"https"}, {"tls/http"}}
+	for _, tt := range tests {
+		t.Run("with "+tt.addrSuffix+" multiaddr", func(t *testing.T) {
+
+			// Create HTTPS test server
+			server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				if r.TLS == nil {
+					t.Error("Mocked Kubo RPC received plain HTTP request instead of HTTPS TLS Handshake")
+				}
+				w.Write([]byte("OK"))
+			}))
+			defer server.Close()
+
+			serverURL, _ := url.Parse(server.URL)
+			_, port, _ := net.SplitHostPort(serverURL.Host)
+
+			// Create Kubo repo
+			node := harness.NewT(t).NewNode().Init()
+
+			// Attempt to talk to remote Kubo RPC endpoint over HTTPS
+			resp := node.RunIPFS("id", "--api", fmt.Sprintf("/ip4/127.0.0.1/tcp/%s/%s", port, tt.addrSuffix))
+
+			// Expect HTTPS error (confirming TLS and https:// were used, and not Cleartext HTTP)
+			require.Error(t, resp.Err)
+			require.Contains(t, resp.Stderr.String(), "Error: tls: failed to verify certificate: x509: certificate signed by unknown authority")
+
+			node.StopDaemon()
+
+		})
+	}
+}