Better exception messages for Tree issues.

Author: dereuromark

src/View/Helper/TreeHelper.php

@@ -12,7 +12,7 @@
 
 use Cake\Core\Configure;
 use Cake\View\Helper;
-use Exception;
+use RuntimeException;
 
 /**
  * Helper to generate tree representations of MPTT or recursively nested data.
@@ -230,7 +230,7 @@ protected function _generate($data, array $config, $parent = null) {
 					$lastChild = true;
 				}
 			} else {
-				throw new Exception('Invalid Tree Structure');
+				throw new RuntimeException('Invalid Tree Structure: ' . print_r($result, true));
 			}
 
 			$activePathElement = null;
@@ -309,7 +309,6 @@ protected function _generate($data, array $config, $parent = null) {
 				if ($numberOfDirectChildren) {
 					$config['depth'] = $depth + 1;
 					$children = $result['children'];
-					//unset($result['children']);
 
 					$return .= $this->_suffix();
 					$return .= $this->_generate($children, $config, $result);
@@ -534,15 +533,15 @@ protected function _attributes($rType, array $elementData = [], $clear = true, b
 	 * @throws \Exception
 	 * @return void
 	 */
-	protected function _markUnrelatedAsHidden(&$tree, array $path, $level = 0) {
+	protected function _markUnrelatedAsHidden(&$tree, array $path, int $level = 0) {
 		extract($this->_config);
 		$siblingIsActive = false;
 		foreach ($tree as $key => &$subTree) {
 			if (is_object($subTree) && method_exists($subTree, 'toArray')) {
 				$subTree = $subTree->toArray();
 			}
 			if (!isset($subTree['children'])) {
-				throw new Exception('Only works with threaded (nested children) results');
+				throw new RuntimeException('Only works with threaded (nested children) results: ' . print_r($subTree, true));
 			}
 
 			if (!empty($path[$level]) && $subTree['id'] == $path[$level]) {

tests/TestCase/View/Helper/TreeHelperTest.php

@@ -6,6 +6,7 @@
 use Cake\ORM\Entity;
 use Cake\Utility\Hash;
 use Cake\View\View;
+use RuntimeException;
 use Shim\TestSuite\TestCase;
 use Tools\View\Helper\TreeHelper;
 
@@ -664,6 +665,86 @@ public function testGenerateWithEntityUsage() {
 		$this->assertTextEquals($expected, $output);
 	}
 
+	/**
+	 * @return void
+	 */
+	public function testGenerateFromArrayWithChildren(): void {
+		$treeData = [
+			[
+				'name' => 'Foo',
+				'children' => [
+					[
+						'name' => 'Bar',
+						'children' => [
+						],
+					],
+					[
+						'name' => 'Baz',
+						'children' => [
+							[
+								'name' => 'Baz Child',
+								'children' => [],
+							],
+						],
+					],
+				],
+			],
+		];
+
+		$output = $this->Tree->generate($treeData);
+		$expected = <<<TEXT
+
+<ul>
+	<li>Foo
+	<ul>
+		<li>Bar</li>
+		<li>Baz
+		<ul>
+			<li>Baz Child</li>
+		</ul>
+		</li>
+	</ul>
+	</li>
+</ul>
+
+TEXT;
+		$output = str_replace(["\t", "\r", "\n"], '', $output);
+		$expected = str_replace(["\t", "\r", "\n"], '', $expected);
+		$this->assertTextEquals($expected, $output);
+	}
+
+	/**
+	 * @return void
+	 */
+	public function testGenerateFromArrayWithChildrenInvalid(): void {
+		$treeData = [
+			[
+				'name' => 'Foo',
+				'children' => [
+					[
+						'name' => 'Bar',
+						'children' => [
+						],
+					],
+					[
+						'name' => 'Baz',
+						'children' => [
+							[
+								'name' => 'Baz Child',
+								//'children' => [] // Missing element
+							],
+						],
+					],
+				],
+			],
+		];
+
+		$this->expectException(RuntimeException::class);
+		$this->expectExceptionMessage('Invalid Tree Structure: Array');
+
+		$this->Tree->generate($treeData);
+	}
+
 	/**
 	 * @param array $data
 	 * @return string|null