Set $minimumCollectionItems to 0 for GeometryCollection and MultiPolygon. Adjusted child classes. Added/update tests.

(cherry picked from commit 534dddc)

Author: grimzy

src/Types/GeometryCollection.php

@@ -19,7 +19,7 @@ class GeometryCollection extends Geometry implements IteratorAggregate, ArrayAcc
      *
      * @var int
      */
-    protected $minimumCollectionItems = 1;
+    protected $minimumCollectionItems = 0;
 
     /**
      * The class of the items in the collection.
@@ -66,6 +66,10 @@ public function __toString()
 
     public static function fromString($wktArgument)
     {
+        if (empty($wktArgument)) {
+            return new static([]);
+        }
+
         $geometry_strings = preg_split('/,\s*(?=[A-Za-z])/', $wktArgument);
 
         return new static(array_map(function ($geometry_string) {

src/Types/MultiLineString.php

@@ -8,6 +8,13 @@
 
 class MultiLineString extends GeometryCollection
 {
+    /**
+     * The minimum number of items required to create this collection.
+     *
+     * @var int
+     */
+    protected $minimumCollectionItems = 1;
+
     /**
      * The class of the items in the collection.
      *

src/Types/MultiPoint.php

@@ -8,6 +8,13 @@
 
 class MultiPoint extends PointCollection
 {
+    /**
+     * The minimum number of items required to create this collection.
+     *
+     * @var int
+     */
+    protected $minimumCollectionItems = 1;
+
     public function toWKT()
     {
         return sprintf('MULTIPOINT(%s)', (string) $this);

src/Types/MultiPolygon.php

@@ -8,6 +8,13 @@
 
 class MultiPolygon extends GeometryCollection
 {
+    /**
+     * The minimum number of items required to create this collection.
+     *
+     * @var int
+     */
+    protected $minimumCollectionItems = 1;
+
     /**
      * The class of the items in the collection.
      *

tests/Integration/SpatialTest.php

@@ -175,6 +175,17 @@ public function testInsertGeometryCollection()
         $this->assertDatabaseHas('geometry', ['id' => $geo->id]);
     }
 
+    public function testInsertEmptyGeometryCollection()
+    {
+        $geo = new GeometryModel();
+
+        $geo->location = new Point(1, 2);
+
+        $geo->multi_geometries = new GeometryCollection([]);
+        $geo->save();
+        $this->assertDatabaseHas('geometry', ['id' => $geo->id]);
+    }
+
     public function testUpdate()
     {
         $geo = new GeometryModel();

tests/Unit/Types/GeometryCollectionTest.php

@@ -33,6 +33,28 @@ public function testJsonSerialize()
         $this->assertSame('{"type":"GeometryCollection","geometries":[{"type":"LineString","coordinates":[[0,0],[1,0],[1,1],[0,1],[0,0]]},{"type":"Point","coordinates":[200,100]}]}', json_encode($this->getGeometryCollection()->jsonSerialize()));
     }
 
+    public function testCanCreateEmptyGeometryCollection()
+    {
+        $geometryCollection = new GeometryCollection([]);
+        $this->assertInstanceOf(GeometryCollection::class, $geometryCollection);
+    }
+
+    public function testFromWKTWithEmptyGeometryCollection()
+    {
+        /**
+         * @var GeometryCollection
+         */
+        $geometryCollection = GeometryCollection::fromWKT('GEOMETRYCOLLECTION()');
+        $this->assertInstanceOf(GeometryCollection::class, $geometryCollection);
+
+        $this->assertEquals(0, $geometryCollection->count());
+    }
+
+    public function testToWKTWithEmptyGeometryCollection()
+    {
+        $this->assertEquals('GEOMETRYCOLLECTION()', (new GeometryCollection([]))->toWKT());
+    }
+
     public function testInvalidArgumentExceptionNotArrayGeometries()
     {
         $this->assertException(

tests/Unit/Types/MultiPolygonTest.php

@@ -68,7 +68,16 @@ public function testJsonSerialize()
         $this->assertSame('{"type":"MultiPolygon","coordinates":[[[[0,0],[1,0],[1,1],[0,1],[0,0]],[[10,10],[20,10],[20,20],[10,20],[10,10]]],[[[100,100],[200,100],[200,200],[100,200],[100,100]]]]}', json_encode($this->getMultiPolygon()));
     }
 
-    public function testInvalidArgumentExceptionNotArrayOfLineString()
+    public function testInvalidArgumentExceptionAtLeastOneEntry()
+    {
+        $this->assertException(
+            InvalidArgumentException::class,
+            'Grimzy\LaravelMysqlSpatial\Types\MultiPolygon must contain at least 1 entry'
+        );
+        $multipolygon = new MultiPolygon([]);
+    }
+
+    public function testInvalidArgumentExceptionNotArrayOfPolygon()
     {
         $this->assertException(
             InvalidArgumentException::class,