Default to hiding flags that start with hyphen unless last arg has a hyphen

command.go

@@ -1,10 +1,6 @@
 package complete
 
-import (
+import "github.com/posener/complete/match"
-	"strings"
-
-	"github.com/posener/complete/match"
-)
 
 // Command represents a command line
 // It holds the data that enables auto completion of command line
@@ -23,11 +19,6 @@ type Command struct {
 	// Global flags that can appear also after a sub command.
 	GlobalFlags Flags
 
-	// FlagsRequirePrefix requires that the prefix is provided before flags are
-	// autocompleted. This allows completion to only display completions for
-	// arguments if for example no hypen is provided.
-	FlagsRequirePrefix string
-
 	// Args are extra arguments that the command accepts, those who are
 	// given without any flag before.
 	Args Predictor
@@ -58,6 +49,14 @@ type Flags map[string]Predictor
 // Predict completion of flags names according to command line arguments
 func (f Flags) Predict(a Args) (prediction []string) {
 	for flag := range f {
+		// If the flag starts with a hyphen, we avoid emiting the prediction
+		// unless the last typed arg contains a hyphen as well.
+		flagHyphenStart := len(flag) != 0 && flag[0] == '-'
+		lastHyphenStart := len(a.Last) != 0 && a.Last[0] == '-'
+		if flagHyphenStart && !lastHyphenStart {
+			continue
+		}
+
 		if match.Prefix(flag, a.Last) {
 			prediction = append(prediction, flag)
 		}
@@ -95,9 +94,7 @@ func (c *Command) predict(a Args) (options []string, only bool) {
 		return predictor.Predict(a), true
 	}
 
-	if c.FlagsRequirePrefix == "" || strings.HasPrefix(a.Last, c.FlagsRequirePrefix) {
+	options = append(options, c.GlobalFlags.Predict(a)...)
-		options = append(options, c.GlobalFlags.Predict(a)...)
-	}
 
 	// if a sub command was entered, we won't add the parent command
 	// completions and we return here.
@@ -112,9 +109,7 @@ func (c *Command) predict(a Args) (options []string, only bool) {
 	}
 
 	options = append(options, c.Sub.Predict(a)...)
-	if c.FlagsRequirePrefix == "" || strings.HasPrefix(a.Last, c.FlagsRequirePrefix) {
+	options = append(options, c.Flags.Predict(a)...)
-		options = append(options, c.Flags.Predict(a)...)
-	}
 	if c.Args != nil {
 		options = append(options, c.Args.Predict(a)...)
 	}

complete_test.go

@@ -25,13 +25,6 @@ func TestCompleter_Complete(t *testing.T) {
 				},
 				Args: PredictFiles("*.md"),
 			},
-			"sub3": {
-				Flags: Flags{
-					"-flag4": PredictAnything,
-					"-flag5": PredictNothing,
-				},
-				FlagsRequirePrefix: "-",
-			},
 		},
 		Flags: Flags{
 			"-o": PredictFiles("*.txt"),
@@ -48,7 +41,7 @@ func TestCompleter_Complete(t *testing.T) {
 	}{
 		{
 			args: "",
-			want: []string{"sub1", "sub2", "sub3", "-h", "-global1", "-o"},
+			want: []string{"sub1", "sub2"},
 		},
 		{
 			args: "-",
@@ -56,7 +49,7 @@ func TestCompleter_Complete(t *testing.T) {
 		},
 		{
 			args: "-h ",
-			want: []string{"sub1", "sub2", "sub3", "-h", "-global1", "-o"},
+			want: []string{"sub1", "sub2"},
 		},
 		{
 			args: "-global1 ", // global1 is known follow flag
@@ -64,7 +57,7 @@ func TestCompleter_Complete(t *testing.T) {
 		},
 		{
 			args: "sub",
-			want: []string{"sub1", "sub2", "sub3"},
+			want: []string{"sub1", "sub2"},
 		},
 		{
 			args: "sub1",
@@ -75,16 +68,16 @@ func TestCompleter_Complete(t *testing.T) {
 			want: []string{"sub2"},
 		},
 		{
-			args: "sub3",
+			args: "sub1 ",
-			want: []string{"sub3"},
+			want: []string{},
 		},
 		{
-			args: "sub1 ",
+			args: "sub1 -",
 			want: []string{"-flag1", "-flag2", "-h", "-global1"},
 		},
 		{
 			args: "sub2 ",
-			want: []string{"./", "dir/", "outer/", "readme.md", "-flag2", "-flag3", "-h", "-global1"},
+			want: []string{"./", "dir/", "outer/", "readme.md"},
 		},
 		{
 			args: "sub2 ./",
@@ -100,7 +93,7 @@ func TestCompleter_Complete(t *testing.T) {
 		},
 		{
 			args: "sub2 -flag2 ",
-			want: []string{"./", "dir/", "outer/", "readme.md", "-flag2", "-flag3", "-h", "-global1"},
+			want: []string{"./", "dir/", "outer/", "readme.md"},
 		},
 		{
 			args: "sub1 -fl",
@@ -115,24 +108,20 @@ func TestCompleter_Complete(t *testing.T) {
 			want: []string{}, // flag1 is unknown follow flag
 		},
 		{
-			args: "sub1 -flag2 ",
+			args: "sub1 -flag2 -",
 			want: []string{"-flag1", "-flag2", "-h", "-global1"},
 		},
-		{
-			args: "sub3 ",
-			want: []string{"-h", "-global1"},
-		},
-		{
-			args: "sub3 -",
-			want: []string{"-flag4", "-flag5", "-h", "-global1"},
-		},
 		{
 			args: "-no-such-flag",
 			want: []string{},
 		},
 		{
 			args: "-no-such-flag ",
-			want: []string{"sub1", "sub2", "sub3", "-h", "-global1", "-o"},
+			want: []string{"sub1", "sub2"},
+		},
+		{
+			args: "-no-such-flag -",
+			want: []string{"-h", "-global1", "-o"},
 		},
 		{
 			args: "no-such-command",
@@ -140,7 +129,7 @@ func TestCompleter_Complete(t *testing.T) {
 		},
 		{
 			args: "no-such-command ",
-			want: []string{"sub1", "sub2", "sub3", "-h", "-global1", "-o"},
+			want: []string{"sub1", "sub2"},
 		},
 		{
 			args: "-o ",
@@ -168,7 +157,7 @@ func TestCompleter_Complete(t *testing.T) {
 		},
 		{
 			args: "-o ./readme.md ",
-			want: []string{"sub1", "sub2", "sub3", "-h", "-global1", "-o"},
+			want: []string{"sub1", "sub2"},
 		},
 		{
 			args: "-o sub2 -flag3 ",