shell completion --format: only show exported fields

go templates only support exported fields, so the completion logic must
filter the private fields out.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

cmd/podman/common/completion.go

@@ -1054,6 +1054,11 @@ func getStructFields(f reflect.Value, prefix string) []string {
 	// loop over all field names
 	for j := 0; j < f.NumField(); j++ {
 		field := f.Type().Field(j)
+		// check if struct field is not exported, templates only use exported fields
+		// PkgPath is always empty for exported fields
+		if field.PkgPath != "" {
+			continue
+		}
 		fname := field.Name
 		suffix := "}}"
 		kind := field.Type.Kind()

cmd/podman/common/completion_test.go

@@ -31,6 +31,12 @@ func (c *Car) Color() string {
 	return ""
 }
 
+// This is for reflect testing required.
+// nolint:unused
+func (c Car) internal() int {
+	return 0
+}
+
 func TestAutocompleteFormat(t *testing.T) {
 	testStruct := struct {
 		Name string
@@ -38,6 +44,7 @@ func TestAutocompleteFormat(t *testing.T) {
 		Car  *Car
 		Car2 *Car
 		*Anonymous
+		private int
 	}{}
 
 	testStruct.Car = &Car{}