diff --git a/pkg/command/arguments_test.go b/pkg/command/arguments_test.go
index bf40585..d443982 100644
--- a/pkg/command/arguments_test.go
+++ b/pkg/command/arguments_test.go
@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	. "git.rob.mx/nidito/chinampa/pkg/command"
+	"github.com/spf13/cobra"
 )
 
 func testCommand() *Command {
@@ -413,3 +414,127 @@ func TestArgumentToDesc(t *testing.T) {
 		})
 	}
 }
+
+func TestArgumentCompletion(t *testing.T) {
+	t.Parallel()
+
+	testcmd := func() (*Command, *cobra.Command) {
+		cc := &cobra.Command{
+			Use:   "test-command",
+			Short: "test",
+		}
+
+		cmd := testCommand()
+		cmd.SetCobra(cc)
+		cmd.SetBindings()
+		return cmd, cc
+	}
+
+	t.Run("empty-args", func(t *testing.T) {
+		t.Parallel()
+		args := &Arguments{}
+
+		cc := &cobra.Command{}
+		values, directive := args.CompletionFunction(cc, []string{}, "")
+
+		if len(values) != 0 {
+			t.Fatal("Values offered for empty argument spec")
+		}
+
+		if directive != cobra.ShellCompDirectiveError {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+
+	t.Run("empty arg spec", func(t *testing.T) {
+		t.Parallel()
+		cmd, cc := testcmd()
+		values, directive := cmd.Arguments.CompletionFunction(cc, []string{}, "")
+
+		if len(values) != 1 || values[0] != "_activeHelp_ " {
+			t.Fatalf("Values offered for empty argument spec: (%d) %v", len(values), values)
+		}
+
+		if directive != cobra.ShellCompDirectiveError {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+
+	t.Run("first-arg", func(t *testing.T) {
+		t.Parallel()
+		cmd, cc := testcmd()
+		choices := []string{"au", "to", "com", "plete"}
+		cmd.Arguments[0].Values = &ValueSource{
+			Static: &choices,
+		}
+
+		values, directive := cmd.Arguments.CompletionFunction(cc, []string{}, "")
+
+		expected := append(choices, "_activeHelp_") // nolint: gocritic
+		if reflect.DeepEqual(expected, values) {
+			t.Fatalf("Unexpected values offered: %v", values)
+		}
+
+		if directive != cobra.ShellCompDirectiveDefault {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+
+	t.Run("first-arg-prefix", func(t *testing.T) {
+		t.Parallel()
+		choices := []string{"au", "to", "com", "plete"}
+		cmd, cc := testcmd()
+		cmd.Arguments[0].Values = &ValueSource{
+			Static: &choices,
+		}
+		values, directive := cmd.Arguments.CompletionFunction(cc, []string{}, "a")
+
+		expected := []string{"au", "_activeHelp_"}
+		if reflect.DeepEqual(expected, values) {
+			t.Fatalf("Unexpected values offered: %v", values)
+		}
+
+		if directive != cobra.ShellCompDirectiveDefault {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+
+	t.Run("variadic-arg", func(t *testing.T) {
+		choices := []string{"au", "to", "com", "plete"}
+		cmd, cc := testcmd()
+		cmd.Arguments[1].Values = &ValueSource{
+			Static: &choices,
+		}
+
+		values, directive := cmd.Arguments.CompletionFunction(cc, []string{"au", ""}, "")
+
+		expected := append(choices, "_activeHelp_") // nolint: gocritic
+		if reflect.DeepEqual(expected, values) {
+			t.Fatalf("Unexpected values offered: %v", values)
+		}
+
+		if directive != cobra.ShellCompDirectiveDefault {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+
+	t.Run("variadic-arg-repeated", func(t *testing.T) {
+		t.Parallel()
+		cmd, cc := testcmd()
+		choices := []string{"au", "to", "com", "plete"}
+		cmd.Arguments[1].Values = &ValueSource{
+			Static: &choices,
+		}
+
+		values, directive := cmd.Arguments.CompletionFunction(cc, []string{"au", "au", ""}, "t")
+
+		expected := []string{"to", "_activeHelp_"}
+		if reflect.DeepEqual(expected, values) {
+			t.Fatalf("Unexpected values offered: %v", values)
+		}
+
+		if directive != cobra.ShellCompDirectiveDefault {
+			t.Fatalf("Unexpected directive: %d", directive)
+		}
+	})
+}