Replace phpunit ResultPrinter with self describing Exception (#396)

phpunit.xml.dist

@@ -1,4 +1,4 @@
-<phpunit bootstrap="vendor/autoload.php" printerClass="Atk4\Core\Phpunit\ResultPrinter" colors="true">
+<phpunit bootstrap="vendor/autoload.php" colors="true">
     <testsuites>
         <testsuite name="tests">
             <directory>tests</directory>

src/Exception.php

@@ -4,12 +4,14 @@
 
 namespace Atk4\Core;
 
+use Atk4\Core\ExceptionRenderer\RendererAbstract;
 use Atk4\Core\Translator\ITranslatorAdapter;
+use PHPUnit\Framework\SelfDescribing;
 
 /**
  * Base exception of all Agile Toolkit exceptions.
  */
-class Exception extends \Exception
+class Exception extends \Exception implements SelfDescribing
 {
     use WarnDynamicPropertyTrait;
 
@@ -55,6 +57,17 @@ public function setMessage(string $message): self
         return $this;
     }
 
+    public function toString(): string
+    {
+        $res = static::class . ': ' . $this->getMessage() . "\n";
+        foreach ($this->getParams() as $param => $value) {
+            $valueStr = RendererAbstract::toSafeString($value, true);
+            $res .= '  ' . $param . ': ' . str_replace("\n", "\n" . '    ', $valueStr) . "\n";
+        }
+
+        return $res;
+    }
+
     /**
      * Return exception message using color sequences.
      *

tests/ExceptionTest.php

@@ -123,6 +123,28 @@ public function testSolution2(): void
         self::assertMatchesRegularExpression('~2nd Solution~', $ret);
     }
 
+    public function testPhpunitSelfDescribing(): void
+    {
+        $m = (new Exception('My exception', 0))
+            ->addMoreInfo('x', 'foo')
+            ->addMoreInfo('y', ['bar' => 2.4, [], [[1]]]);
+
+        self::assertSame(
+            <<<'EOF'
+                Atk4\Core\Exception: My exception
+                  x: 'foo'
+                  y: [
+                      'bar': 2.4,
+                      0: [],
+                      1: [
+                          ...
+                        ]
+                    ]
+                EOF . "\n", // NL in the string is not parsed by Netbeans, see https://github.com/apache/netbeans/issues/4345
+            $m->toString()
+        );
+    }
+
     public function testExceptionFallback(): void
     {
         $m = new ExceptionTestThrowError('test', 2);