diff --git a/tests/Config/ConfigurationTest.php b/tests/Config/ConfigurationTest.php
index ae83dda..a979f9c 100644
--- a/tests/Config/ConfigurationTest.php
+++ b/tests/Config/ConfigurationTest.php
@@ -36,6 +36,15 @@ class ConfigurationTest extends TestCase
         $this->validateConfig($config);
     }
 
+    public function testThrowsIfMultipleDirectoriesPassedAndOneNotFound(): void
+    {
+        $config = $this->getValidConfig();
+        $fakeDir = "abc/def/ghi";
+        $config['directories'] = ['./', $fakeDir];
+        $this->expectExceptionMessage("\"abc\/def\/ghi\" is not a directory!");
+        $this->validateConfig($config);
+    }
+
     public function testThrowsIfNoColoursExist(): void
     {
         $config = $this->getValidConfig();
@@ -60,14 +69,46 @@ class ConfigurationTest extends TestCase
         $this->validateConfig($config);
     }
 
-    private function validateConfig(array $config): void
+    public function testDefaultSizeIs32Pixels(): void
     {
-        $this->processor->processConfiguration($this->configuration, [$config]);
+        $config = $this->getValidConfig();
+        unset($config['default']['size']);
+        $validatedConfig = $this->validateConfig($config);
+
+        $this->assertSame(32, $validatedConfig['default']['size']);
+    }
+
+    public function testSizeIsSetToProvidedValue(): void
+    {
+        $config = $this->getValidConfig();
+        $config['default']['size'] = 99;
+        $validatedConfig = $this->validateConfig($config);
+
+        $this->assertSame(99, $validatedConfig['default']['size']);
+    }
+
+    public function testDefaultColourIsPrimary(): void
+    {
+        $config = $this->getValidConfig();
+        unset($config['default']['colour']);
+        $validatedConfig = $this->validateConfig($config);
+
+        $this->assertSame('primary', $validatedConfig['default']['colour']);
+    }
+
+    private function validateConfig(array $config): array
+    {
+        return $this->processor->processConfiguration($this->configuration, [$config]);
     }
 
     private function getValidConfig(): array
     {
         return [
+            'default' => [
+                'colour' => 'primary',
+                'size' => 32
+            ],
+
             'directories' => [
                 './',
             ],
@@ -84,5 +125,4 @@ class ConfigurationTest extends TestCase
             ],
         ];
     }
-
 }