Some PHP 7.1 compatible code.

app/Helpers/Attachments/AttachmentHelper.php

@@ -99,7 +99,7 @@ class AttachmentHelper implements AttachmentHelperInterface
      *
      * @return bool
      */
-    public function saveAttachmentsForModel(Model $model, array $files = null): bool
+    public function saveAttachmentsForModel(Model $model, ?array $files): bool
     {
         if (is_array($files)) {
             foreach ($files as $entry) {

app/Helpers/Attachments/AttachmentHelperInterface.php

@@ -55,6 +55,6 @@ interface AttachmentHelperInterface
      *
      * @return bool
      */
-    public function saveAttachmentsForModel(Model $model, array $files = null): bool;
+    public function saveAttachmentsForModel(Model $model, ?array $files): bool;
 
 }

app/Http/Controllers/BudgetController.php

@@ -171,7 +171,7 @@ class BudgetController extends Controller
      *
      * @return View
      */
-    public function index(string $moment = null)
+    public function index(?string $moment)
     {
         $range = Preferences::get('viewRange', '1M')->data;
         $start = session('start', new Carbon);

app/Http/Controllers/Chart/BudgetController.php

@@ -163,7 +163,7 @@ class BudgetController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function expenseAsset(Budget $budget, BudgetLimit $budgetLimit = null)
+    public function expenseAsset(Budget $budget, ?BudgetLimit $budgetLimit)
     {
         $cache = new CacheProperties;
         $cache->addProperty($budget->id);
@@ -208,7 +208,7 @@ class BudgetController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function expenseCategory(Budget $budget, BudgetLimit $budgetLimit = null)
+    public function expenseCategory(Budget $budget, ?BudgetLimit $budgetLimit)
     {
         $cache = new CacheProperties;
         $cache->addProperty($budget->id);
@@ -255,7 +255,7 @@ class BudgetController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function expenseExpense(Budget $budget, BudgetLimit $budgetLimit = null)
+    public function expenseExpense(Budget $budget, ?BudgetLimit $budgetLimit)
     {
         $cache = new CacheProperties;
         $cache->addProperty($budget->id);

app/Http/breadcrumbs.php

@@ -805,7 +805,7 @@ Breadcrumbs::register(
  * MASS TRANSACTION EDIT / DELETE
  */
 Breadcrumbs::register(
-    'transactions.mass.edit', function (BreadCrumbGenerator $breadcrumbs, Collection $journals) {
+    'transactions.mass.edit', function (BreadCrumbGenerator $breadcrumbs, Collection $journals): void {
 
     if ($journals->count() > 0) {
         $journalIds = $journals->pluck('id')->toArray();
@@ -817,6 +817,7 @@ Breadcrumbs::register(
     }
 
     $breadcrumbs->parent('index');
+    return;
 }
 );
 

app/Repositories/Account/AccountRepository.php

@@ -500,7 +500,7 @@ class AccountRepository implements AccountRepositoryInterface
      *
      * @return null|string
      */
-    private function filterIban(string $iban = null)
+    private function filterIban(?string $iban)
     {
         if (is_null($iban)) {
             return null;

app/Repositories/RuleGroup/RuleGroupRepository.php

@@ -44,7 +44,7 @@ class RuleGroupRepository implements RuleGroupRepositoryInterface
      *
      * @return bool
      */
-    public function destroy(RuleGroup $ruleGroup, RuleGroup $moveTo = null): bool
+    public function destroy(RuleGroup $ruleGroup, ?RuleGroup $moveTo): bool
     {
         /** @var Rule $rule */
         foreach ($ruleGroup->rules as $rule) {

app/Repositories/RuleGroup/RuleGroupRepositoryInterface.php

@@ -39,7 +39,7 @@ interface RuleGroupRepositoryInterface
      *
      * @return bool
      */
-    public function destroy(RuleGroup $ruleGroup, RuleGroup $moveTo = null): bool;
+    public function destroy(RuleGroup $ruleGroup, ?RuleGroup $moveTo): bool;
 
     /**
      * @param int $ruleGroupId

app/Repositories/Tag/TagRepository.php

@@ -253,7 +253,7 @@ class TagRepository implements TagRepositoryInterface
      *
      * @return string
      */
-    public function sumOfTag(Tag $tag, Carbon $start = null, Carbon $end = null): string
+    public function sumOfTag(Tag $tag, ?Carbon $start, ?Carbon $end): string
     {
         /** @var JournalCollectorInterface $collector */
         $collector = app(JournalCollectorInterface::class);

app/Repositories/Tag/TagRepositoryInterface.php

@@ -133,7 +133,7 @@ interface TagRepositoryInterface
      *
      * @return string
      */
-    public function sumOfTag(Tag $tag, Carbon $start = null, Carbon $end = null): string;
+    public function sumOfTag(Tag $tag, ?Carbon $start, ?Carbon $end): string;
 
     /**
      * @param Tag $tag

app/Support/Navigation.php

@@ -135,7 +135,7 @@ class Navigation
      *
      * @return Carbon
      */
-    public function endOfX(Carbon $theCurrentEnd, string $repeatFreq, Carbon $maxDate = null): Carbon
+    public function endOfX(Carbon $theCurrentEnd, string $repeatFreq, ?Carbon $maxDate): Carbon
     {
         $functionMap = [
             '1D'        => 'endOfDay',

app/Support/Twig/General.php

@@ -147,7 +147,7 @@ class General extends Twig_Extension
     protected function balance(): Twig_SimpleFilter
     {
         return new Twig_SimpleFilter(
-            'balance', function (Account $account = null): string {
+            'balance', function (?Account $account): string {
             if (is_null($account)) {
                 return 'NULL';
             }