Fix test coverage.

Author: drupol

spec/drupol/phptree/Exporter/AsciiSpec.php

@@ -5,6 +5,7 @@
 namespace spec\drupol\phptree\Exporter;
 
 use drupol\phptree\Exporter\Ascii;
+use drupol\phptree\Node\Node;
 use drupol\phptree\Node\ValueNode;
 use PhpSpec\ObjectBehavior;
 
@@ -99,4 +100,19 @@ public function it_can_export_to_ascii()
             ->export($tree)
             ->shouldReturn($expected);
     }
+
+    public function it_can_throw_an_error_when_tree_is_not_a_valuenode()
+    {
+        $tree = new Node();
+
+        foreach (\range('A', 'Z') as $key => $value) {
+            $nodes[$value] = new Node();
+        }
+
+        $tree->add(...\array_values($nodes));
+
+        $this
+            ->shouldThrow(\InvalidArgumentException::class)
+            ->during('export', [$tree]);
+    }
 }

spec/drupol/phptree/Exporter/SimpleArraySpec.php

@@ -5,6 +5,7 @@
 namespace spec\drupol\phptree\Exporter;
 
 use drupol\phptree\Exporter\SimpleArray;
+use drupol\phptree\Node\Node;
 use drupol\phptree\Node\ValueNode;
 use PhpSpec\ObjectBehavior;
 
@@ -78,4 +79,19 @@ public function it_can_export_to_an_array()
             ->export($tree)
             ->shouldReturn($return);
     }
+
+    public function it_can_throw_an_error_when_tree_is_not_a_valuenode()
+    {
+        $tree = new Node();
+
+        foreach (\range('A', 'Z') as $key => $value) {
+            $nodes[$value] = new Node();
+        }
+
+        $tree->add(...\array_values($nodes));
+
+        $this
+            ->shouldThrow(\InvalidArgumentException::class)
+            ->during('export', [$tree]);
+    }
 }

spec/drupol/phptree/Exporter/TextSpec.php

@@ -5,6 +5,7 @@
 namespace spec\drupol\phptree\Exporter;
 
 use drupol\phptree\Exporter\Text;
+use drupol\phptree\Node\Node;
 use drupol\phptree\Node\ValueNode;
 use PhpSpec\ObjectBehavior;
 
@@ -34,4 +35,19 @@ public function it_can_export_to_text()
             ->export($tree)
             ->shouldReturn('[root [A [C [G] [H]] [D [I] [J]]] [B [E] [F]]]');
     }
+
+    public function it_can_throw_an_error_when_tree_is_not_a_valuenode()
+    {
+        $tree = new Node();
+
+        foreach (\range('A', 'Z') as $key => $value) {
+            $nodes[$value] = new Node();
+        }
+
+        $tree->add(...\array_values($nodes));
+
+        $this
+            ->shouldThrow(\InvalidArgumentException::class)
+            ->during('export', [$tree]);
+    }
 }