Add ignore property for each Mutator in JSON schema.

Fixes #698

Add tests to prevent such issues in the future for any new mutators.
Add `helmich/phpunit-json-assert` for convenient JSON schema testing in PHPUnit

composer.json

@@ -60,6 +60,7 @@
         "symfony/process": "3.4.2"
     },
     "require-dev": {
+        "helmich/phpunit-json-assert": "^2.1",
         "phpunit/phpunit": "^7.5"
     },
     "config": {

resources/schema.json

@@ -126,6 +126,7 @@
                                 "type": "object",
                                 "additionalProperties": false,
                                 "properties": {
+                                    "ignore": {"type": "array", "items": {"type": "string"}},
                                     "settings": {
                                         "type": "object",
                                         "additionalProperties": false,
@@ -155,6 +156,7 @@
                                 "type": "object",
                                 "additionalProperties": false,
                                 "properties": {
+                                    "ignore": {"type": "array", "items": {"type": "string"}},
                                     "settings": {
                                         "type": "object",
                                         "additionalProperties": false,
@@ -203,6 +205,7 @@
                                 "type": "object",
                                 "additionalProperties": false,
                                 "properties": {
+                                    "ignore": {"type": "array", "items": {"type": "string"}},
                                     "settings": {
                                         "type": "object",
                                         "additionalProperties": false,

tests/resources/InfectionConfigJsonSchemaTest.php

@@ -0,0 +1,87 @@
+<?php
+/**
+ * This code is licensed under the BSD 3-Clause License.
+ *
+ * Copyright (c) 2017-2019, Maks Rafalko
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the copyright holder nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+declare(strict_types=1);
+
+namespace Infection\Tests\resources;
+
+use Helmich\JsonAssert\JsonAssertions;
+use PHPUnit\Framework\TestCase;
+
+class InfectionConfigJsonSchemaTest extends TestCase
+{
+    use JsonAssertions;
+
+    private const SCHEMA_FILE = __DIR__ . '/../../resources/schema.json';
+
+    /**
+     * @var array|null
+     */
+    private static $schema;
+
+    /**
+     * @dataProvider mutatorsProvider
+     */
+    public function test_all_mutators_support_ignore_key(string $mutator): void
+    {
+        $infectionJson = <<<"JSON"
+{
+    "timeout": 1,
+    "source": {"directories": ["src"]},
+    "mutators": {
+        "$mutator": {
+            "ignore": ["Foo\\\\Bar::baz"]
+        }
+    }
+}
+JSON;
+
+        self::assertJsonDocumentMatchesSchema($infectionJson, self::getSchema());
+    }
+
+    public function mutatorsProvider(): \Generator
+    {
+        foreach (array_keys(self::getSchema()['properties']['mutators']['properties']) as $mutator) {
+            yield $mutator => [$mutator];
+        }
+    }
+
+    private static function getSchema()
+    {
+        if (self::$schema !== null) {
+            return self::$schema;
+        }
+
+        return self::$schema = json_decode(file_get_contents(self::SCHEMA_FILE), true);
+    }
+}