Add belongs-to-many caching functionality.

src/CacheKey.php

@@ -19,8 +19,8 @@ class CacheKey
 
     public function __construct(
         array $eagerLoad,
-        Model $model,
-        Builder $query
+        $model,
+        $query
     ) {
         $this->eagerLoad = $eagerLoad;
         $this->model = $model;
@@ -54,7 +54,9 @@ protected function getIdColumn(string $idColumn) : string
 
     protected function getLimitClause() : string
     {
-        if (! $this->query->limit) {
+        if (! property_exists($this->query, "limit")
+            || ! $this->query->limit
+        ) {
             return "";
         }
 
@@ -74,7 +76,9 @@ protected function getModelSlug() : string
 
     protected function getOffsetClause() : string
     {
-        if (! $this->query->offset) {
+        if (! property_exists($this->query, "offset")
+            || ! $this->query->offset
+        ) {
             return "";
         }
 
@@ -83,6 +87,12 @@ protected function getOffsetClause() : string
 
     protected function getOrderByClauses() : string
     {
+        if (! property_exists($this->query, "orders")
+            || ! $this->query->orders
+        ) {
+            return "";
+        }
+
         $orders = collect($this->query->orders);
 
         return $orders
@@ -100,12 +110,15 @@ protected function getQueryColumns(array $columns) : string
     {
         if (($columns === ["*"]
                 || $columns === [])
-            && ! $this->query->columns
+            && (! property_exists($this->query, "columns")
+                || ! $this->query->columns)
         ) {
             return "";
         }
 
-        if ($this->query->columns) {
+        if (property_exists($this->query, "columns")
+            && $this->query->columns
+        ) {
             return "_" . implode("_", $this->query->columns);
         }
 
@@ -302,7 +315,9 @@ protected function getWheres(array $wheres) : Collection
     {
         $wheres = collect($wheres);
 
-        if ($wheres->isEmpty()) {
+        if ($wheres->isEmpty()
+            && property_exists($this->query, "wheres")
+        ) {
             $wheres = collect($this->query->wheres);
         }
 

src/CacheTags.php

@@ -16,8 +16,8 @@ class CacheTags
 
     public function __construct(
         array $eagerLoad,
-        Model $model,
-        Builder $query
+        $model,
+        $query
     ) {
         $this->eagerLoad = $eagerLoad;
         $this->model = $model;

src/CachedBelongsToMany.php

@@ -0,0 +1,15 @@
+<?php namespace GeneaLabs\LaravelModelCaching;
+
+use Fico7489\Laravel\Pivot\Traits\FiresPivotEventsTrait;
+use GeneaLabs\LaravelModelCaching\Traits\Buildable;
+use GeneaLabs\LaravelModelCaching\Traits\BuilderCaching;
+use GeneaLabs\LaravelModelCaching\Traits\Caching;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
+
+class CachedBelongsToMany extends BelongsToMany
+{
+    use Buildable;
+    use BuilderCaching;
+    use Caching;
+    use FiresPivotEventsTrait;
+}