Validate generated Clover XML against Clover XSD

Author: sebastianbergmann

tests/tests/Report/CloverTest.php

@@ -9,6 +9,13 @@
  */
 namespace SebastianBergmann\CodeCoverage\Report;
 
+use const PHP_EOL;
+use function libxml_clear_errors;
+use function libxml_get_errors;
+use function libxml_use_internal_errors;
+use function sprintf;
+use function trim;
+use DOMDocument;
 use PHPUnit\Framework\Attributes\CoversClass;
 use SebastianBergmann\CodeCoverage\TestCase;
 
@@ -19,7 +26,7 @@ public function testLineCoverageForBankAccountTest(): void
     {
         $clover = new Clover;
 
-        $this->assertStringMatchesFormatFile(
+        $this->validateAndAssert(
             TEST_FILES_PATH . 'BankAccount-clover-line.xml',
             $clover->process($this->getLineCoverageForBankAccount(), null, 'BankAccount'),
         );
@@ -29,7 +36,7 @@ public function testPathCoverageForBankAccountTest(): void
     {
         $clover = new Clover;
 
-        $this->assertStringMatchesFormatFile(
+        $this->validateAndAssert(
             TEST_FILES_PATH . 'BankAccount-clover-path.xml',
             $clover->process($this->getPathCoverageForBankAccount(), null, 'BankAccount'),
         );
@@ -39,7 +46,7 @@ public function testCloverForFileWithIgnoredLines(): void
     {
         $clover = new Clover;
 
-        $this->assertStringMatchesFormatFile(
+        $this->validateAndAssert(
             TEST_FILES_PATH . 'ignored-lines-clover.xml',
             $clover->process($this->getCoverageForFileWithIgnoredLines()),
         );
@@ -49,9 +56,43 @@ public function testCloverForClassWithAnonymousFunction(): void
     {
         $clover = new Clover;
 
-        $this->assertStringMatchesFormatFile(
+        $this->validateAndAssert(
             TEST_FILES_PATH . 'class-with-anonymous-function-clover.xml',
             $clover->process($this->getCoverageForClassWithAnonymousFunction()),
         );
     }
+
+    /**
+     * @param non-empty-string $expectationFile
+     * @param non-empty-string $cloverXml
+     */
+    private function validateAndAssert(string $expectationFile, string $cloverXml): void
+    {
+        libxml_use_internal_errors(true);
+
+        $document = new DOMDocument;
+        $document->loadXML($cloverXml);
+
+        if (!$document->schemaValidate(__DIR__ . '/../../_files/clover.xsd')) {
+            $buffer = 'Generated XML document does not validate against Clover schema:' . PHP_EOL . PHP_EOL;
+
+            foreach (libxml_get_errors() as $error) {
+                $buffer .= sprintf(
+                    '- Line %d: %s' . PHP_EOL,
+                    $error->line,
+                    trim($error->message),
+                );
+            }
+
+            $buffer .= PHP_EOL;
+        }
+
+        libxml_clear_errors();
+
+        if (isset($buffer)) {
+            $this->fail($buffer);
+        }
+
+        $this->assertStringMatchesFormatFile($expectationFile, $cloverXml);
+    }
 }