fix(validator): skip validation for non-JSON content types instead of failing

Fixes a regression introduced in v0.6.0 (PR #19) where endpoints with
non-JSON content types (e.g. text/html) incorrectly returned a failure
result instead of skipping validation. Now returns success when no
JSON-compatible content type is found in the spec.

Fixes #20

Author: wadakatu

src/OpenApiResponseValidator.php

@@ -10,7 +10,6 @@
 use Opis\JsonSchema\Validator;
 
 use function array_keys;
-use function implode;
 use function json_decode;
 use function json_encode;
 use function str_ends_with;
@@ -70,11 +69,7 @@ public function validate(
         $jsonContentType = $this->findJsonContentType($content);
 
         if ($jsonContentType === null) {
-            $definedTypes = array_keys($content);
-
-            return OpenApiValidationResult::failure([
-                "No JSON-compatible content type found for {$method} {$matchedPath} (status {$statusCode}) in '{$specName}' spec. Defined content types: " . implode(', ', $definedTypes),
-            ]);
+            return OpenApiValidationResult::success($matchedPath);
         }
 
         if (!isset($content[$jsonContentType]['schema'])) {

tests/Integration/ResponseValidationTest.php

@@ -64,11 +64,12 @@ public function full_pipeline_v30_validate_and_track_coverage(): void
 
         // Check coverage
         $coverage = OpenApiCoverageTracker::computeCoverage('petstore-3.0');
-        $this->assertSame(5, $coverage['total']);
+        $this->assertSame(6, $coverage['total']);
         $this->assertSame(2, $coverage['coveredCount']);
         $this->assertContains('GET /v1/pets', $coverage['covered']);
         $this->assertContains('POST /v1/pets', $coverage['covered']);
         $this->assertContains('GET /v1/health', $coverage['uncovered']);
+        $this->assertContains('GET /v1/logout', $coverage['uncovered']);
         $this->assertContains('DELETE /v1/pets/{petId}', $coverage['uncovered']);
         $this->assertContains('GET /v1/pets/{petId}', $coverage['uncovered']);
     }

tests/Unit/OpenApiCoverageTrackerTest.php

@@ -67,21 +67,21 @@ public function compute_coverage_returns_correct_stats(): void
         $result = OpenApiCoverageTracker::computeCoverage('petstore-3.0');
 
         // See tests/fixtures/specs/petstore-3.0.json for the full endpoint list
-        $this->assertSame(5, $result['total']);
+        $this->assertSame(6, $result['total']);
         $this->assertSame(2, $result['coveredCount']);
         $this->assertCount(2, $result['covered']);
-        $this->assertCount(3, $result['uncovered']);
+        $this->assertCount(4, $result['uncovered']);
     }
 
     #[Test]
     public function compute_coverage_with_no_coverage(): void
     {
         $result = OpenApiCoverageTracker::computeCoverage('petstore-3.0');
 
-        $this->assertSame(5, $result['total']);
+        $this->assertSame(6, $result['total']);
         $this->assertSame(0, $result['coveredCount']);
         $this->assertCount(0, $result['covered']);
-        $this->assertCount(5, $result['uncovered']);
+        $this->assertCount(6, $result['uncovered']);
     }
 
     #[Test]

tests/Unit/OpenApiResponseValidatorTest.php

@@ -211,7 +211,7 @@ public function v30_problem_json_empty_body_fails(): void
     }
 
     #[Test]
-    public function v30_content_without_json_compatible_type_fails(): void
+    public function v30_non_json_content_type_skips_validation(): void
     {
         $result = $this->validator->validate(
             'petstore-3.0',
@@ -221,9 +221,8 @@ public function v30_content_without_json_compatible_type_fails(): void
             '<error>Unsupported</error>',
         );
 
-        $this->assertFalse($result->isValid());
-        $this->assertStringContainsString('No JSON-compatible content type found', $result->errors()[0]);
-        $this->assertStringContainsString('application/xml', $result->errors()[0]);
+        $this->assertTrue($result->isValid());
+        $this->assertSame('/v1/pets', $result->matchedPath());
     }
 
     #[Test]
@@ -260,6 +259,21 @@ public function v30_json_content_type_without_schema_skips_validation(): void
         $this->assertSame('/v1/pets', $result->matchedPath());
     }
 
+    #[Test]
+    public function v30_text_html_only_content_type_skips_validation(): void
+    {
+        $result = $this->validator->validate(
+            'petstore-3.0',
+            'GET',
+            '/v1/logout',
+            200,
+            '<html><body>Logged out</body></html>',
+        );
+
+        $this->assertTrue($result->isValid());
+        $this->assertSame('/v1/logout', $result->matchedPath());
+    }
+
     // ========================================
     // OAS 3.1 tests
     // ========================================
@@ -324,7 +338,7 @@ public function v31_problem_json_valid_response_passes(): void
     }
 
     #[Test]
-    public function v31_content_without_json_compatible_type_fails(): void
+    public function v31_non_json_content_type_skips_validation(): void
     {
         $result = $this->validator->validate(
             'petstore-3.1',
@@ -334,9 +348,8 @@ public function v31_content_without_json_compatible_type_fails(): void
             '<error>Unsupported</error>',
         );
 
-        $this->assertFalse($result->isValid());
-        $this->assertStringContainsString('No JSON-compatible content type found', $result->errors()[0]);
-        $this->assertStringContainsString('application/xml', $result->errors()[0]);
+        $this->assertTrue($result->isValid());
+        $this->assertSame('/v1/pets', $result->matchedPath());
     }
 
     #[Test]

tests/fixtures/specs/petstore-3.0.json

@@ -143,6 +143,24 @@
                 }
             }
         },
+        "/v1/logout": {
+            "get": {
+                "summary": "Logout page",
+                "operationId": "logout",
+                "responses": {
+                    "200": {
+                        "description": "Logout confirmation page",
+                        "content": {
+                            "text/html": {
+                                "schema": {
+                                    "type": "string"
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        },
         "/v1/health": {
             "get": {
                 "summary": "Health check",