Function TestEmptyPositionalArgsAfterFlag

command_test.go:6149–6192

Regression for #2234: an empty positional arg following a flag used to be dropped along with every arg after it.

(t *testing.T)

// Regression for #2234: an empty positional arg following a flag used to be
// dropped along with every arg after it.
func TestEmptyPositionalArgsAfterFlag(t *testing.T) {
	testCases := []struct {
		Name         string
		Args         []string
		ExpectedArgs []string
		ExpectedFlag string
	}{
		{
			Name:         "empty arg after equals-form flag",
			Args:         []string{"app", "-f=something", "", "arg2", "arg3"},
			ExpectedArgs: []string{"", "arg2", "arg3"},
			ExpectedFlag: "something",
		},
		{
			Name:         "empty arg after space-form flag",
			Args:         []string{"app", "-f", "something", "", "arg2"},
			ExpectedArgs: []string{"", "arg2"},
			ExpectedFlag: "something",
		},
	}

	for _, tc := range testCases {
		t.Run(tc.Name, func(t *testing.T) {
			var args []string
			var flagVal string

			cmd := &Command{
				Flags: []Flag{
					&StringFlag{Name: "f"},
				},
				Action: func(_ context.Context, cmd *Command) error {
					args = cmd.Args().Slice()
					flagVal = cmd.String("f")
					return nil
				},
			}

			err := cmd.Run(buildTestContext(t), tc.Args)
			assert.NoError(t, err)
			assert.Equal(t, tc.ExpectedArgs, args)
			assert.Equal(t, tc.ExpectedFlag, flagVal)
		})
	}
}

func TestFlagEqualsEmptyValue(t *testing.T) {
	t.Run("--flag= sets empty string", func(t *testing.T) {