add more tests

parse.go

@@ -333,10 +333,10 @@ func setSlice(dest reflect.Value, values []string) error {
 		if err := setScalar(v.Elem(), s); err != nil {
 			return err
 		}
-		if ptr {
-			v = v.Addr()
+		if !ptr {
+			v = v.Elem()
 		}
-		dest.Set(reflect.Append(dest, v.Elem()))
+		dest.Set(reflect.Append(dest, v))
 	}
 	return nil
 }

parse_test.go

@@ -1,6 +1,7 @@
 package arg
 
 import (
+	"os"
 	"strings"
 	"testing"
 
@@ -69,6 +70,28 @@ func TestShortFlag(t *testing.T) {
 	assert.Equal(t, "xyz", args.Foo)
 }
 
+func TestInvalidShortFlag(t *testing.T) {
+	var args struct {
+		Foo string `arg:"-foo"`
+	}
+	err := parse("", &args)
+	assert.Error(t, err)
+}
+
+func TestLongFlag(t *testing.T) {
+	var args struct {
+		Foo string `arg:"--abc"`
+	}
+
+	err := parse("-abc xyz", &args)
+	require.NoError(t, err)
+	assert.Equal(t, "xyz", args.Foo)
+
+	err = parse("--abc xyz", &args)
+	require.NoError(t, err)
+	assert.Equal(t, "xyz", args.Foo)
+}
+
 func TestCaseSensitive(t *testing.T) {
 	var args struct {
 		Lower bool `arg:"-v"`
@@ -104,6 +127,19 @@ func TestPositional(t *testing.T) {
 	assert.Equal(t, "", args.Output)
 }
 
+func TestPositionalPointer(t *testing.T) {
+	var args struct {
+		Input  string    `arg:"positional"`
+		Output []*string `arg:"positional"`
+	}
+	err := parse("foo bar baz", &args)
+	require.NoError(t, err)
+	assert.Equal(t, "foo", args.Input)
+	bar := "bar"
+	baz := "baz"
+	assert.Equal(t, []*string{&bar, &baz}, args.Output)
+}
+
 func TestRequiredPositional(t *testing.T) {
 	var args struct {
 		Input  string `arg:"positional"`
@@ -132,3 +168,191 @@ func TestMultiple(t *testing.T) {
 	assert.Equal(t, []int{1, 2, 3}, args.Foo)
 	assert.Equal(t, []string{"x", "y", "z"}, args.Bar)
 }
+
+func TestMultipleWithEq(t *testing.T) {
+	var args struct {
+		Foo []int
+		Bar []string
+	}
+	err := parse("--foo 1 2 3 --bar=x", &args)
+	require.NoError(t, err)
+	assert.Equal(t, []int{1, 2, 3}, args.Foo)
+	assert.Equal(t, []string{"x"}, args.Bar)
+}
+
+func TestExemptField(t *testing.T) {
+	var args struct {
+		Foo string
+		Bar interface{} `arg:"-"`
+	}
+	err := parse("--foo xyz", &args)
+	require.NoError(t, err)
+	assert.Equal(t, "xyz", args.Foo)
+}
+
+func TestUnknownField(t *testing.T) {
+	var args struct {
+		Foo string
+	}
+	err := parse("--bar xyz", &args)
+	assert.Error(t, err)
+}
+
+func TestMissingRequired(t *testing.T) {
+	var args struct {
+		Foo string   `arg:"required"`
+		X   []string `arg:"positional"`
+	}
+	err := parse("x", &args)
+	assert.Error(t, err)
+}
+
+func TestMissingValue(t *testing.T) {
+	var args struct {
+		Foo string
+	}
+	err := parse("--foo", &args)
+	assert.Error(t, err)
+}
+
+func TestInvalidInt(t *testing.T) {
+	var args struct {
+		Foo int
+	}
+	err := parse("--foo=xyz", &args)
+	assert.Error(t, err)
+}
+
+func TestInvalidUint(t *testing.T) {
+	var args struct {
+		Foo uint
+	}
+	err := parse("--foo=xyz", &args)
+	assert.Error(t, err)
+}
+
+func TestInvalidFloat(t *testing.T) {
+	var args struct {
+		Foo float64
+	}
+	err := parse("--foo xyz", &args)
+	require.Error(t, err)
+}
+
+func TestInvalidBool(t *testing.T) {
+	var args struct {
+		Foo bool
+	}
+	err := parse("--foo=xyz", &args)
+	require.Error(t, err)
+}
+
+func TestInvalidIntSlice(t *testing.T) {
+	var args struct {
+		Foo []int
+	}
+	err := parse("--foo 1 2 xyz", &args)
+	require.Error(t, err)
+}
+
+func TestInvalidPositional(t *testing.T) {
+	var args struct {
+		Foo int `arg:"positional"`
+	}
+	err := parse("xyz", &args)
+	require.Error(t, err)
+}
+
+func TestInvalidPositionalSlice(t *testing.T) {
+	var args struct {
+		Foo []int `arg:"positional"`
+	}
+	err := parse("1 2 xyz", &args)
+	require.Error(t, err)
+}
+
+func TestNoMoreOptions(t *testing.T) {
+	var args struct {
+		Foo string
+		Bar []string `arg:"positional"`
+	}
+	err := parse("abc -- --foo xyz", &args)
+	require.NoError(t, err)
+	assert.Equal(t, "", args.Foo)
+	assert.Equal(t, []string{"abc", "--foo", "xyz"}, args.Bar)
+}
+
+func TestHelpFlag(t *testing.T) {
+	var args struct {
+		Foo string
+		Bar interface{} `arg:"-"`
+	}
+	err := parse("--help", &args)
+	assert.Equal(t, ErrHelp, err)
+}
+
+func TestPanicOnNonPointer(t *testing.T) {
+	var args struct{}
+	assert.Panics(t, func() {
+		parse("", args)
+	})
+}
+
+func TestPanicOnNonStruct(t *testing.T) {
+	var args string
+	assert.Panics(t, func() {
+		parse("", &args)
+	})
+}
+
+func TestUnsupportedType(t *testing.T) {
+	var args struct {
+		Foo interface{}
+	}
+	err := parse("--foo", &args)
+	assert.Error(t, err)
+}
+
+func TestUnsupportedSliceElement(t *testing.T) {
+	var args struct {
+		Foo []interface{}
+	}
+	err := parse("--foo", &args)
+	assert.Error(t, err)
+}
+
+func TestUnknownTag(t *testing.T) {
+	var args struct {
+		Foo string `arg:"this_is_not_valid"`
+	}
+	err := parse("--foo xyz", &args)
+	assert.Error(t, err)
+}
+
+func TestParse(t *testing.T) {
+	var args struct {
+		Foo string
+	}
+	os.Args = []string{"example", "--foo", "bar"}
+	err := Parse(&args)
+	require.NoError(t, err)
+	assert.Equal(t, "bar", args.Foo)
+}
+
+func TestParseError(t *testing.T) {
+	var args struct {
+		Foo string `arg:"this_is_not_valid"`
+	}
+	os.Args = []string{"example", "--bar"}
+	err := Parse(&args)
+	assert.Error(t, err)
+}
+
+func TestMustParse(t *testing.T) {
+	var args struct {
+		Foo string
+	}
+	os.Args = []string{"example", "--foo", "bar"}
+	MustParse(&args)
+	assert.Equal(t, "bar", args.Foo)
+}