chore: import upstream snapshot with attribution

internal/cmdutil/completion_test.go

@@ -0,0 +1,79 @@
+// Copyright (c) 2026 Lark Technologies Pte. Ltd.
+// SPDX-License-Identifier: MIT
+
+package cmdutil
+
+import (
+	"runtime"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/spf13/cobra"
+)
+
+func TestSetFlagCompletionsEnabled_RoundTrip(t *testing.T) {
+	t.Cleanup(func() { SetFlagCompletionsEnabled(false) })
+
+	if FlagCompletionsEnabled() {
+		t.Fatal("expected default false (completions disabled by default)")
+	}
+	SetFlagCompletionsEnabled(true)
+	if !FlagCompletionsEnabled() {
+		t.Fatal("expected true after Set(true)")
+	}
+	SetFlagCompletionsEnabled(false)
+	if FlagCompletionsEnabled() {
+		t.Fatal("expected false after Set(false)")
+	}
+}
+
+// When disabled, a *cobra.Command must be collectable after the caller drops
+// its reference — i.e. the wrapper did not touch cobra's global map.
+func TestRegisterFlagCompletion_Disabled_DoesNotRetainCommand(t *testing.T) {
+	SetFlagCompletionsEnabled(false)
+	t.Cleanup(func() { SetFlagCompletionsEnabled(false) })
+
+	const N = 5
+	var collected atomic.Int32
+	func() {
+		for range N {
+			cmd := &cobra.Command{Use: "x"}
+			cmd.Flags().String("foo", "", "")
+			RegisterFlagCompletion(cmd, "foo", func(_ *cobra.Command, _ []string, _ string) ([]cobra.Completion, cobra.ShellCompDirective) {
+				return nil, cobra.ShellCompDirectiveNoFileComp
+			})
+			runtime.SetFinalizer(cmd, func(_ *cobra.Command) { collected.Add(1) })
+		}
+	}()
+	// Finalizers run on a dedicated goroutine after GC; loop to give it time.
+	for range 30 {
+		runtime.GC()
+		time.Sleep(20 * time.Millisecond)
+	}
+	if got := collected.Load(); int(got) != N {
+		t.Fatalf("expected %d *cobra.Command finalizers to fire when completions disabled, got %d", N, got)
+	}
+}
+
+// When enabled, the registered completion must be reachable via cobra.
+func TestRegisterFlagCompletion_Enabled_DoesRegister(t *testing.T) {
+	SetFlagCompletionsEnabled(true)
+	t.Cleanup(func() { SetFlagCompletionsEnabled(false) })
+
+	cmd := &cobra.Command{Use: "x"}
+	cmd.Flags().String("foo", "", "")
+	want := []cobra.Completion{"a", "b"}
+	RegisterFlagCompletion(cmd, "foo", func(_ *cobra.Command, _ []string, _ string) ([]cobra.Completion, cobra.ShellCompDirective) {
+		return want, cobra.ShellCompDirectiveNoFileComp
+	})
+
+	fn, ok := cmd.GetFlagCompletionFunc("foo")
+	if !ok {
+		t.Fatal("expected completion func to be registered")
+	}
+	got, _ := fn(cmd, nil, "")
+	if len(got) != 2 || got[0] != "a" || got[1] != "b" {
+		t.Fatalf("unexpected completion result: %v", got)
+	}
+}