diff --git a/src/Plugin/Validation/Constraint/GeoConstraintValidator.php b/src/Plugin/Validation/Constraint/GeoConstraintValidator.php
index 2b7cde0..bc94d75 100644
--- a/src/Plugin/Validation/Constraint/GeoConstraintValidator.php
+++ b/src/Plugin/Validation/Constraint/GeoConstraintValidator.php
@@ -27,7 +27,7 @@ public function validate($value, Constraint $constraint) {
       }
 
       if (!$valid_geometry) {
-        $this->context->addViolation($constraint->message, array('@value' => $value));
+        $this->context->addViolation($constraint->message, ['@value' => $value]);
       }
     }
   }
diff --git a/tests/src/Kernel/ConstraintsTest.php b/tests/src/Kernel/ConstraintsTest.php
new file mode 100644
index 0000000..d8ace53
--- /dev/null
+++ b/tests/src/Kernel/ConstraintsTest.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace Drupal\Tests\geofield\Kernel;
+
+use Drupal\geofield\Plugin\Validation\Constraint\GeoConstraint;
+use Drupal\geofield\Plugin\Validation\Constraint\GeoConstraintValidator;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests geofield constraints.
+ *
+ * @group geofield
+ */
+class ConstraintsTest extends KernelTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = ['geofield'];
+
+  /**
+   * Tests GeoType constraint.
+   *
+   * @covers \Drupal\geofield\Plugin\Validation\Constraint\GeoConstraintValidator
+   * @covers \Drupal\geofield\Plugin\Validation\Constraint\GeoConstraint
+   *
+   * @dataProvider geoProvider
+   */
+  public function testGeoConstraint($coordinates, $expected_violation_count) {
+    // Check message in constraint.
+    $constraint = new GeoConstraint();
+    $this->assertEquals('"@value" is not a valid geospatial content.', $constraint->message, 'Correct constraint message found.');
+
+    $execution_context = $this->getMockBuilder('\Drupal\Core\TypedData\Validation\ExecutionContext')
+      ->disableOriginalConstructor()
+      ->getMock();
+
+    if ($expected_violation_count) {
+      $execution_context->expects($this->exactly($expected_violation_count))
+        ->method('addViolation')
+        ->with($constraint->message, ['@value' => $coordinates]);
+    }
+    else {
+      $execution_context->expects($this->exactly($expected_violation_count))
+        ->method('addViolation');
+    }
+
+    $validator = new GeoConstraintValidator();
+    $validator->initialize($execution_context);
+
+    $validator->validate($coordinates, $constraint);
+  }
+
+  /**
+   * Provides test data for testGeoConstraint().
+   */
+  public function geoProvider() {
+    return [
+      'valid POINT' => ['POINT (40 -3)', 0],
+      'invalid POAINT' => ['POAINT (40 -3)', 1],
+      'invalid POINT' => ['POINT (40 -A)', 1],
+    ];
+  }
+
+}