Skip dummy parts and parameters

src/classes/Configuration.php

@@ -147,6 +147,11 @@ public function parts(): Collection
 				throw new InvalidArgumentException('Invalid part ' . $num);
 			}
 
+			// skip dummy parts
+			if (is_string($part['articleNr'] ?? null) !== true) {
+				continue;
+			}
+
 			$parts[] = new Part($part);
 		}
 

src/classes/Part.php

@@ -94,6 +94,11 @@ public function parameters(): Parameters
 				throw new InvalidArgumentException('Invalid parameter ' . $num);
 			}
 
+			// skip dummy parameters
+			if (is_string($parameter['value'] ?? null) !== true) {
+				continue;
+			}
+
 			$parameter = new Parameter($parameter);
 
 			// double-check uninitialized property before access (normally should not happen);

tests/Roomle/ConfigurationTest.php

@@ -111,16 +111,23 @@ public function testParts()
 		$configuration = new Configuration([
 			'parts' => [
 				[
+					'articleNr'   => '12345',
 					'componentId' => 'some:component1',
 					'label'       => 'Some component 1'
 				],
 				[
+					'articleNr'   => '12345',
 					'componentId' => 'some:component1',
 					'label'       => 'Some component 1 with different properties'
 				],
 				[
+					'articleNr'   => '23456',
 					'componentId' => 'some:component2',
 					'label'       => 'Some component 2'
+				],
+				[
+					'componentId' => 'some:component3',
+					'label'       => 'Some component 3 without article number'
 				]
 			]
 		]);

tests/Roomle/PartTest.php

@@ -66,6 +66,10 @@ public function testParameters()
 					'type'     => 'Decimal',
 					'unitType' => 'length',
 					'value'    => '456.0'
+				],
+				[
+					'key'      => 'internal',
+					'label'    => 'Internal parameter without value'
 				]
 			]
 		]);
@@ -106,7 +110,8 @@ public function testParameters_Invalid2()
 		$part = new Part([
 			'parameters' => [
 				[
-					'label' => 'Some parameter without key'
+					'label' => 'Some parameter without key',
+					'value' => '123'
 				]
 			]
 		]);