test: add coverage tests across backend + fix mock for PENDING checkout support

New test files cover previously untested paths across DAV, validators,
S3, Square, mw, bookings, user, and payments packages.

Includes mock fix: HoldCheckouts flag on MockClient allows tests to
pause auto-complete goroutine for testing PENDING checkout states.

Coverage: 50.4% → 65.0% (+14.6pp)

backend/handlers/admin/custom_services.go

@@ -442,6 +442,17 @@ func PromoteCustomService(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	var existingCount int
+	err = tx.QueryRow(r.Context(), `SELECT COUNT(*) FROM services WHERE name = $1 AND is_active = true`, name.String).Scan(&existingCount)
+	if err != nil {
+		http.Error(w, "Failed to check for duplicate name: "+err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if existingCount > 0 {
+		http.Error(w, "A service with this name already exists", http.StatusConflict)
+		return
+	}
+
 	var newServiceID string
 	err = tx.QueryRow(r.Context(), `
 		INSERT INTO services (name, description, price, duration_minutes, minimum_age_required, created_by)
@@ -449,10 +460,6 @@ func PromoteCustomService(w http.ResponseWriter, r *http.Request) {
 		RETURNING id
 	`, name.String, desc, price, durationMinutes, minimumAgeRequired, createdBy).Scan(&newServiceID)
 	if err != nil {
-		if err.Error() == "pq: duplicate key value violates unique constraint" || err.Error() == "duplicate key value violates unique constraint" {
-			http.Error(w, "A service with this name already exists", http.StatusConflict)
-			return
-		}
 		http.Error(w, "Failed to create service: "+err.Error(), http.StatusInternalServerError)
 		return
 	}

backend/handlers/admin/custom_services_test.go

@@ -660,6 +660,41 @@ func TestCustomServices_Promote(t *testing.T) {
 	defer fixtures.DeleteService(tx, newServiceID)
 }
 
+func TestCustomServices_Promote_DuplicateName(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin user: %v", err)
+	}
+	defer fixtures.DeleteUser(tx, adminID)
+
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+	defer fixtures.DeleteService(tx, serviceID)
+
+	csID, err := fixtures.CreateTestCustomService(tx)
+	if err != nil {
+		t.Fatalf("failed to create custom service: %v", err)
+	}
+	defer fixtures.DeleteCustomService(tx, csID)
+
+	_, err = tx.Exec(context.Background(),
+		"UPDATE custom_services SET name = 'Test Service' WHERE id = $1", csID)
+	if err != nil {
+		t.Fatalf("failed to update custom service name: %v", err)
+	}
+
+	handler := http.HandlerFunc(PromoteCustomService)
+	w := makeCustomServiceRequest(handler, "POST", "/api/admin/custom-services/"+csID+"/promote", nil, adminID, ctx)
+
+	if w.Code != http.StatusConflict {
+		t.Errorf("expected status 409, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
 // TestCustomServices_Promote_NotFound verifies that promoting a non-existent custom service returns 404.
 func TestCustomServices_Promote_NotFound(t *testing.T) {
 	ctx, tx := testutils.SetupTestTx(t)

backend/handlers/admin/discount_campaigns_test.go

@@ -527,3 +527,442 @@ func TestGetCampaignStats_NotFound(t *testing.T) {
 		t.Errorf("expected 404 for nonexistent campaign, got %d", w.Code)
 	}
 }
+
+// =============================================================================
+// Additional Update Coverage Tests
+// =============================================================================
+
+// TestUpdateDiscountCampaign_EmptyID verifies empty campaign ID returns 404.
+func TestUpdateDiscountCampaign_EmptyID(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	req := UpdateCampaignRequest{Name: stringPtr("Test")}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/", req, ctx, adminID)
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for empty ID, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_NonExistentValidID verifies a valid-format but
+// non-existent campaign ID returns 404.
+func TestUpdateDiscountCampaign_NonExistentValidID(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	newName := "Test"
+	req := UpdateCampaignRequest{Name: &newName}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/aabbccddee00", req, ctx, adminID)
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for nonexistent campaign, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_InvalidJSON verifies malformed JSON body returns 400.
+func TestUpdateDiscountCampaign_InvalidJSON(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	req := httptest.NewRequest("PUT", "/api/admin/discount-campaigns/"+campaignID, strings.NewReader("not json"))
+	req.Header.Set("Content-Type", "application/json")
+
+	rctx := chi.NewRouteContext()
+	rctx.URLParams.Add("id", campaignID)
+	ctx = context.WithValue(ctx, chi.RouteCtxKey, rctx)
+	ctx = context.WithValue(ctx, mw.UserIDKey, adminID)
+	ctx = context.WithValue(ctx, mw.UserRoleKey, "admin")
+	req = req.WithContext(ctx)
+
+	w := httptest.NewRecorder()
+	http.HandlerFunc(UpdateDiscountCampaign).ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for invalid JSON, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_ValidatorError verifies struct validation errors return 400.
+func TestUpdateDiscountCampaign_ValidatorError(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	// Empty name (non-nil pointer, empty string) should fail min=1 validation
+	emptyName := ""
+	req := UpdateCampaignRequest{Name: &emptyName}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for validation error, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_InvalidDiscountPercent verifies discount_percent
+// out of range returns 400.
+func TestUpdateDiscountCampaign_InvalidDiscountPercent(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+
+	t.Run("zero_percent", func(t *testing.T) {
+		zero := 0.0
+		req := UpdateCampaignRequest{DiscountPercent: &zero}
+		w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+		if w.Code != http.StatusBadRequest {
+			t.Errorf("expected 400 for zero discount, got %d. body: %s", w.Code, w.Body.String())
+		}
+	})
+
+	t.Run("over_100", func(t *testing.T) {
+		over := 150.0
+		req := UpdateCampaignRequest{DiscountPercent: &over}
+		w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+		if w.Code != http.StatusBadRequest {
+			t.Errorf("expected 400 for discount >100, got %d. body: %s", w.Code, w.Body.String())
+		}
+	})
+}
+
+// TestUpdateDiscountCampaign_InvalidStartDateFormat verifies bad start_date
+// format returns 400.
+func TestUpdateDiscountCampaign_InvalidStartDateFormat(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertTimeBasedCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	badDate := "not-a-date"
+	req := UpdateCampaignRequest{StartDate: &badDate}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for bad start date, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_InvalidEndDateFormat verifies bad end_date
+// format returns 400.
+func TestUpdateDiscountCampaign_InvalidEndDateFormat(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertTimeBasedCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	badDate := "not-a-date"
+	req := UpdateCampaignRequest{EndDate: &badDate}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for bad end date, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// TestUpdateDiscountCampaign_InvalidMilestoneValue verifies milestone_value
+// out of range returns 400.
+func TestUpdateDiscountCampaign_InvalidMilestoneValue(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+
+	t.Run("zero_value", func(t *testing.T) {
+		zero := 0
+		req := UpdateCampaignRequest{MilestoneValue: &zero}
+		w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+		if w.Code != http.StatusBadRequest {
+			t.Errorf("expected 400 for zero milestone value, got %d. body: %s", w.Code, w.Body.String())
+		}
+	})
+
+	t.Run("negative_value", func(t *testing.T) {
+		neg := -1
+		req := UpdateCampaignRequest{MilestoneValue: &neg}
+		w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+		if w.Code != http.StatusBadRequest {
+			t.Errorf("expected 400 for negative milestone value, got %d. body: %s", w.Code, w.Body.String())
+		}
+	})
+}
+
+// TestUpdateDiscountCampaign_UpdateDescription verifies updating description
+// only.
+func TestUpdateDiscountCampaign_UpdateDescription(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	desc := "New description"
+	req := UpdateCampaignRequest{Description: &desc}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.Description == nil || *campaign.Description != "New description" {
+		t.Errorf("expected description 'New description', got %v", campaign.Description)
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateDiscountPercent verifies updating discount
+// percent successfully.
+func TestUpdateDiscountCampaign_UpdateDiscountPercent(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	dp := 25.0
+	req := UpdateCampaignRequest{DiscountPercent: &dp}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.DiscountPercent != 25 {
+		t.Errorf("expected discount percent 25, got %f", campaign.DiscountPercent)
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateScope verifies updating scope successfully.
+func TestUpdateDiscountCampaign_UpdateScope(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	scope := "all_bookings"
+	req := UpdateCampaignRequest{Scope: &scope}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.Scope == nil || *campaign.Scope != "all_bookings" {
+		t.Errorf("expected scope 'all_bookings', got %v", campaign.Scope)
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateDates verifies updating start_date and
+// end_date successfully.
+func TestUpdateDiscountCampaign_UpdateDates(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertTimeBasedCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	startDate := fmt.Sprintf("%sZ", clock.Now().Add(24*time.Hour).Format("2006-01-02T15:04:05"))
+	endDate := fmt.Sprintf("%sZ", clock.Now().Add(14*24*time.Hour).Format("2006-01-02T15:04:05"))
+	req := UpdateCampaignRequest{
+		StartDate: &startDate,
+		EndDate:   &endDate,
+	}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.StartDate == nil {
+		t.Error("expected start_date to be set")
+	}
+	if campaign.EndDate == nil {
+		t.Error("expected end_date to be set")
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateMilestoneFields verifies updating milestone
+// fields successfully.
+func TestUpdateDiscountCampaign_UpdateMilestoneFields(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	mt := "per_user_booking_count"
+	mv := 10
+	mu := "bookings"
+	req := UpdateCampaignRequest{
+		MilestoneType:  &mt,
+		MilestoneValue: &mv,
+		MilestoneUnit:  &mu,
+	}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.MilestoneType == nil || *campaign.MilestoneType != "per_user_booking_count" {
+		t.Errorf("expected milestone type 'per_user_booking_count', got %v", campaign.MilestoneType)
+	}
+	if campaign.MilestoneValue == nil || *campaign.MilestoneValue != 10 {
+		t.Errorf("expected milestone value 10, got %v", campaign.MilestoneValue)
+	}
+	if campaign.MilestoneUnit == nil || *campaign.MilestoneUnit != "bookings" {
+		t.Errorf("expected milestone unit 'bookings', got %v", campaign.MilestoneUnit)
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateMaxRedemptions verifies updating
+// max_redemptions successfully.
+func TestUpdateDiscountCampaign_UpdateMaxRedemptions(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Test", 10, "draft")
+
+	mr := 200
+	req := UpdateCampaignRequest{MaxRedemptions: &mr}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.MaxRedemptions == nil || *campaign.MaxRedemptions != 200 {
+		t.Errorf("expected max redemptions 200, got %v", campaign.MaxRedemptions)
+	}
+}
+
+// TestUpdateDiscountCampaign_UpdateMultipleFields verifies updating several
+// fields at once: name, description, discount_percent, status, max_redemptions.
+func TestUpdateDiscountCampaign_UpdateMultipleFields(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	adminID, err := fixtures.CreateTestAdminUser(tx)
+	if err != nil {
+		t.Fatalf("failed to create admin: %v", err)
+	}
+	testAdminID = adminID
+
+	campaignID := insertMilestoneCampaign(t, ctx, tx, adminID, "Original Name", 10, "draft")
+
+	newName := "Updated Name"
+	newDesc := "Updated description"
+	newDP := 20.0
+	newStatus := "active"
+	newMR := 50
+	req := UpdateCampaignRequest{
+		Name:            &newName,
+		Description:     &newDesc,
+		DiscountPercent: &newDP,
+		Status:          &newStatus,
+		MaxRedemptions:  &newMR,
+	}
+	handler := http.HandlerFunc(UpdateDiscountCampaign)
+	w := makeCampaignRequest(handler, "PUT", "/api/admin/discount-campaigns/"+campaignID, req, ctx, adminID)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d. body: %s", w.Code, w.Body.String())
+	}
+
+	var campaign DiscountCampaign
+	if err := json.Unmarshal(w.Body.Bytes(), &campaign); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if campaign.Name != "Updated Name" {
+		t.Errorf("expected name 'Updated Name', got %q", campaign.Name)
+	}
+	if campaign.Description == nil || *campaign.Description != "Updated description" {
+		t.Errorf("expected description 'Updated description', got %v", campaign.Description)
+	}
+	if campaign.DiscountPercent != 20 {
+		t.Errorf("expected discount percent 20, got %f", campaign.DiscountPercent)
+	}
+	if campaign.Status != "active" {
+		t.Errorf("expected status 'active', got %q", campaign.Status)
+	}
+	if campaign.MaxRedemptions == nil || *campaign.MaxRedemptions != 50 {
+		t.Errorf("expected max redemptions 50, got %v", campaign.MaxRedemptions)
+	}
+}

backend/handlers/admin/patch_tests_test.go

@@ -3,11 +3,16 @@
 package admin
 
 import (
+	"bytes"
+	"context"
 	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"crussell/testutils"
 	"crussell/testutils/fixtures"
+
+	"github.com/go-chi/chi/v5"
 )
 
 func TestPatchTests_CRUD(t *testing.T) {
@@ -63,3 +68,266 @@ func TestPatchTests_CRUD(t *testing.T) {
 func strPtr(s string) *string {
 	return &s
 }
+
+// =============================================================================
+// Create Patch Test - Validation Tests
+// =============================================================================
+
+func TestCreatePatchTest_ValidationErrors(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+
+	handler := http.HandlerFunc(CreatePatchTest)
+
+	t.Run("empty_name", func(t *testing.T) {
+		req := CreatePatchTestRequest{
+			Name:                "",
+			NoticeDurationHours: 24,
+			ExpiryMonths:        6,
+		}
+		w := makeAdminRequest(handler, "POST", "/api/admin/patch-tests", req, ctx)
+		if w.Code != http.StatusBadRequest {
+			t.Errorf("expected 400 for empty name, got %d. body: %s", w.Code, w.Body.String())
+		}
+	})
+
+	_, err := tx.Exec(ctx, `SELECT 1`)
+	if err != nil {
+		t.Fatalf("tx check failed: %v", err)
+	}
+}
+
+// =============================================================================
+// Update Patch Test - Error Tests
+// =============================================================================
+
+func TestUpdatePatchTest_NotFound(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	newName := "Updated"
+	updateReq := UpdatePatchTestRequest{Name: &newName}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/nonexistent-id", updateReq, ctx)
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for nonexistent patch test, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// =============================================================================
+// Delete Patch Test - Error Tests
+// =============================================================================
+
+func TestDeletePatchTest_NotFound(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	w = makeAdminRequest(http.HandlerFunc(DeletePatchTest), "DELETE", "/api/admin/patch-tests/nonexistent-id", nil, ctx)
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for nonexistent patch test, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+// =============================================================================
+// Update Patch Test - Individual Field Update Tests
+// =============================================================================
+
+func TestUpdatePatchTest_UpdateDescription(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	var created struct {
+		ID string `json:"id"`
+	}
+	parseResponseBody(w, &created)
+
+	updateReq := UpdatePatchTestRequest{Description: strPtr("Updated Description")}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/"+created.ID, updateReq, ctx)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d, body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestUpdatePatchTest_UpdateNoticeDuration(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	var created struct {
+		ID string `json:"id"`
+	}
+	parseResponseBody(w, &created)
+
+	noticeDuration := 48
+	updateReq := UpdatePatchTestRequest{NoticeDurationHours: &noticeDuration}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/"+created.ID, updateReq, ctx)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d, body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestUpdatePatchTest_UpdateExpiryMonths(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	var created struct {
+		ID string `json:"id"`
+	}
+	parseResponseBody(w, &created)
+
+	expiryMonths := 12
+	updateReq := UpdatePatchTestRequest{ExpiryMonths: &expiryMonths}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/"+created.ID, updateReq, ctx)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d, body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestUpdatePatchTest_UpdateServiceIDs(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	var created struct {
+		ID string `json:"id"`
+	}
+	parseResponseBody(w, &created)
+
+	updateReq := UpdatePatchTestRequest{ServiceIDs: []string{serviceID}}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/"+created.ID, updateReq, ctx)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d, body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestUpdatePatchTest_InvalidJSON(t *testing.T) {
+	ctx, _ := testutils.SetupTestTx(t)
+
+	req := httptest.NewRequest("PUT", "/api/admin/patch-tests/abcdef123456", bytes.NewReader([]byte(`{invalid}`)))
+	req.Header.Set("Content-Type", "application/json")
+	rctx := chi.NewRouteContext()
+	rctx.URLParams.Add("id", "abcdef123456")
+	ctx = context.WithValue(ctx, chi.RouteCtxKey, rctx)
+	req = req.WithContext(ctx)
+
+	w := httptest.NewRecorder()
+	http.HandlerFunc(UpdatePatchTest).ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for invalid JSON, got %d. body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestUpdatePatchTest_ValidationError(t *testing.T) {
+	ctx, tx := testutils.SetupTestTx(t)
+	serviceID, err := fixtures.CreateTestService(tx)
+	if err != nil {
+		t.Fatalf("failed to create service: %v", err)
+	}
+
+	createReq := CreatePatchTestRequest{
+		Name:                "Test",
+		NoticeDurationHours: 24,
+		ExpiryMonths:        6,
+		ServiceIDs:          []string{serviceID},
+	}
+	w := makeAdminRequest(http.HandlerFunc(CreatePatchTest), "POST", "/api/admin/patch-tests", createReq, ctx)
+	if w.Code != http.StatusCreated {
+		t.Fatalf("failed to create patch test: %d", w.Code)
+	}
+
+	var created struct {
+		ID string `json:"id"`
+	}
+	parseResponseBody(w, &created)
+
+	var longName string
+	for i := 0; i < 201; i++ {
+		longName += "a"
+	}
+	updateReq := UpdatePatchTestRequest{Name: &longName}
+	w = makeAdminRequest(http.HandlerFunc(UpdatePatchTest), "PUT", "/api/admin/patch-tests/"+created.ID, updateReq, ctx)
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("expected 400 for validation error, got %d. body: %s", w.Code, w.Body.String())
+	}
+}

backend/handlers/admin/settings_test.go

@@ -3,12 +3,15 @@
 package admin
 
 import (
+	"context"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
 
 	"crussell/testutils"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func intPtr(i int) *int             { return &i }
@@ -1036,3 +1039,22 @@ func TestUpdateBusinessSettings_DisableVATRegistration(t *testing.T) {
 		t.Errorf("expected IsVATRegistered to be false")
 	}
 }
+
+func TestGetPublicBusinessInfo_DBError(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	req := httptest.NewRequest("GET", "/business-info", nil).WithContext(ctx)
+	w := httptest.NewRecorder()
+	GetPublicBusinessInfo(w, req)
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+}
+
+func TestGetBusinessSettings_DBError(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	req := httptest.NewRequest("GET", "/api/admin/settings", nil)
+	req = req.WithContext(ctx)
+	w := httptest.NewRecorder()
+	GetBusinessSettings(w, req)
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+}