test: warning not to test cli [ci skip]

cli/internal/errors_test.go

@@ -0,0 +1,38 @@
+package internal
+
+import (
+	"github.com/urfave/cli/v2"
+)
+
+// Testing functions that call os.Exit
+// https://stackoverflow.com/questions/26225513/how-to-test-os-exit-scenarios-in-go
+// https://talks.golang.org/2014/testing.slide#23
+
+var testapp = &cli.App{
+	Name:  "abra",
+	Usage: `The Co-op Cloud command-line utility belt 🎩🐇`,
+}
+
+// not testing output as that changes. just if it exits with code 1
+// does not work because of some weird errors on cli's part. Its a hard lib to test effectively.
+// func TestShowSubcommandHelpAndError(t *testing.T) {
+// 	if os.Getenv("HelpAndError") == "1" {
+// 		ShowSubcommandHelpAndError(cli.NewContext(testapp, nil, nil), errors.New("Test error"))
+// 		return
+// 	}
+// 	cmd := exec.Command(os.Args[0], "-test.run=TestShowSubcommandHelpAndError")
+// 	cmd.Env = append(os.Environ(), "HelpAndError=1")
+// 	var out bytes.Buffer
+// 	cmd.Stderr = &out
+// 	err := cmd.Run()
+// 	println(out.String())
+// 	if !strings.Contains(out.String(), "Test error") {
+
+// 		t.Fatalf("expected command to show the error causing the exit, did not get correct stdout output")
+// 	}
+
+// 	if e, ok := err.(*exec.ExitError); ok && !e.Success() {
+// 		return
+// 	}
+// 	t.Fatalf("process ran with err %v, want exit status 1", err)
+// }