Merge pull request urfave#1839 from dearchap/issue_1838

Fix:(issue_1838) Use primary name for required flag error

command.go

@@ -943,10 +943,15 @@ func (cmd *Command) checkRequiredFlag(f Flag) (bool, string) {
 		flagName := ""
 
 		for _, key := range f.Names() {
-			flagName = key
+			// use the first name to return since that is the
+			// primary flag name
+			if flagName == "" {
+				flagName = key
+			}
 
 			if cmd.IsSet(strings.TrimSpace(key)) {
 				flagPresent = true
+				break
 			}
 		}
 

command_test.go

@@ -3835,7 +3835,7 @@ func TestCheckRequiredFlags(t *testing.T) {
 			expectedAnError:       true,
 			expectedErrorContents: []string{"Required flag \"names\" not set"},
 			flags: []Flag{
-				&StringSliceFlag{Name: "names, n", Required: true},
+				&StringSliceFlag{Name: "names", Aliases: []string{"n"}, Required: true},
 			},
 		},
 		{

flag_bool_with_inverse_test.go

@@ -309,7 +309,7 @@ func TestBoolWithInverseRequired(t *testing.T) {
 		{
 			toBeSet: false,
 			value:   false,
-			err:     fmt.Errorf(`Required flag "env" not set`),
+			err:     fmt.Errorf(`Required flag "no-env" not set`),
 		},
 		{
 			args: []string{"--env", "--no-env"},