From 4acf378f96adc451115a1aafca83713bd5776f18 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Matou=C5=A1=20Dzivjak?= <matousdzivjak@gmail.com>
Date: Fri, 27 Mar 2026 22:06:35 +0100
Subject: [PATCH] fix(commands): handle nil list responses safely

Add a shared helper for pointer-backed slice responses and use it in the remaining list commands that still dereferenced API results directly.

This keeps empty or partial SDK responses from turning into nil-pointer panics and aligns them with the already-defensive transactions command.
---
 internal/commands/checkouts/checkouts.go |  5 +++--
 internal/commands/customers/customers.go |  5 +++--
 internal/commands/payouts/payouts.go     |  6 ++++--
 internal/commands/util/util.go           |  7 +++++++
 internal/commands/util/util_test.go      | 14 ++++++++++++++
 5 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/internal/commands/checkouts/checkouts.go b/internal/commands/checkouts/checkouts.go
index 8163c5b..bd7a82a 100644
--- a/internal/commands/checkouts/checkouts.go
+++ b/internal/commands/checkouts/checkouts.go
@@ -162,8 +162,9 @@ func listCheckouts(ctx context.Context, cmd *cli.Command) error {
 		return display.PrintJSON(appCtx.Output, checkoutList)
 	}
 
-	rows := make([][]attribute.Value, 0, len(*checkoutList))
-	for _, checkout := range *checkoutList {
+	checkouts := util.SliceOrEmpty(checkoutList)
+	rows := make([][]attribute.Value, 0, len(checkouts))
+	for _, checkout := range checkouts {
 		status := "-"
 		if checkout.Status != nil {
 			status = string(*checkout.Status)
diff --git a/internal/commands/customers/customers.go b/internal/commands/customers/customers.go
index f64d71d..57e9e92 100644
--- a/internal/commands/customers/customers.go
+++ b/internal/commands/customers/customers.go
@@ -222,8 +222,9 @@ func listPaymentInstruments(ctx context.Context, cmd *cli.Command) error {
 		return display.PrintJSON(appCtx.Output, instruments)
 	}
 
-	rows := make([][]attribute.Value, 0, len(*instruments))
-	for _, instrument := range *instruments {
+	paymentInstruments := util.SliceOrEmpty(instruments)
+	rows := make([][]attribute.Value, 0, len(paymentInstruments))
+	for _, instrument := range paymentInstruments {
 		rows = append(rows, []attribute.Value{
 			attribute.OptionalStringValue(instrument.Token),
 			attribute.OptionalValue(instrument.Type),
diff --git a/internal/commands/payouts/payouts.go b/internal/commands/payouts/payouts.go
index 3bc490b..a1be5b9 100644
--- a/internal/commands/payouts/payouts.go
+++ b/internal/commands/payouts/payouts.go
@@ -12,6 +12,7 @@ import (
 	"github.com/sumup/sumup-go/datetime"
 
 	"github.com/sumup/sumup-cli/internal/app"
+	"github.com/sumup/sumup-cli/internal/commands/util"
 	"github.com/sumup/sumup-cli/internal/display"
 	"github.com/sumup/sumup-cli/internal/display/attribute"
 )
@@ -97,8 +98,9 @@ func listPayouts(ctx context.Context, cmd *cli.Command) error {
 		return display.PrintJSON(appCtx.Output, payoutList)
 	}
 
-	rows := make([][]attribute.Value, 0, len(*payoutList))
-	for _, payout := range *payoutList {
+	payouts := util.SliceOrEmpty(payoutList)
+	rows := make([][]attribute.Value, 0, len(payouts))
+	for _, payout := range payouts {
 		fee := attribute.OptionalValue(payout.Fee)
 		if payout.Fee != nil {
 			fee = attribute.ValueOf(fmt.Sprintf("%.2f", *payout.Fee))
diff --git a/internal/commands/util/util.go b/internal/commands/util/util.go
index 60f2cf6..1d58e9d 100644
--- a/internal/commands/util/util.go
+++ b/internal/commands/util/util.go
@@ -58,3 +58,10 @@ func BoolLabel(value *bool) string {
 	}
 	return "No"
 }
+
+func SliceOrEmpty[S ~[]E, E any](value *S) S {
+	if value == nil {
+		return S{}
+	}
+	return *value
+}
diff --git a/internal/commands/util/util_test.go b/internal/commands/util/util_test.go
index 467106d..187cf4d 100644
--- a/internal/commands/util/util_test.go
+++ b/internal/commands/util/util_test.go
@@ -83,6 +83,20 @@ func TestBoolLabel(t *testing.T) {
 	})
 }
 
+func TestSliceOrEmpty(t *testing.T) {
+	t.Parallel()
+
+	t.Run("returns empty slice for nil pointer", func(t *testing.T) {
+		var values *[]string
+		assert.Empty(t, util.SliceOrEmpty(values))
+	})
+
+	t.Run("returns dereferenced slice when present", func(t *testing.T) {
+		values := []string{"a", "b"}
+		assert.Equal(t, values, util.SliceOrEmpty(&values))
+	})
+}
+
 func TestTimeOrDash(t *testing.T) {
 	t.Parallel()