Stop Infection execution with 0 exit code when git diff filter retu…

…rns empty result (no files to be mutated)

Fixes #1599

This will improve the speed of CI builds and immediately stop Infection execution.

Example: if `README.md` is updated on the root of the folder, we don't want/need to run Infection against the whole project.

src/Command/RunCommand.php

@@ -53,6 +53,7 @@
 use Infection\FileSystem\Locator\FileOrDirectoryNotFound;
 use Infection\FileSystem\Locator\Locator;
 use Infection\Logger\ConsoleLogger;
+use Infection\Logger\GitHub\NoFilesInDiffToMutate;
 use Infection\Metrics\MinMsiCheckFailed;
 use Infection\Process\Runner\InitialTestsFailed;
 use Infection\TestFramework\TestFrameworkTypes;
@@ -329,26 +330,30 @@ protected function executeCommand(IO $io): bool
         $container = $this->createContainer($io, $logger);
         $consoleOutput = new ConsoleOutput($logger);
 
-        $this->startUp($container, $consoleOutput, $logger, $io);
-
-        $engine = new Engine(
-            $container->getConfiguration(),
-            $container->getTestFrameworkAdapter(),
-            $container->getCoverageChecker(),
-            $container->getEventDispatcher(),
-            $container->getInitialTestsRunner(),
-            $container->getMemoryLimiter(),
-            $container->getMutationGenerator(),
-            $container->getMutationTestingRunner(),
-            $container->getMinMsiChecker(),
-            $consoleOutput,
-            $container->getMetricsCalculator(),
-            $container->getTestFrameworkExtraOptionsFilter()
-        );
-
         try {
+            $this->startUp($container, $consoleOutput, $logger, $io);
+
+            $engine = new Engine(
+                $container->getConfiguration(),
+                $container->getTestFrameworkAdapter(),
+                $container->getCoverageChecker(),
+                $container->getEventDispatcher(),
+                $container->getInitialTestsRunner(),
+                $container->getMemoryLimiter(),
+                $container->getMutationGenerator(),
+                $container->getMutationTestingRunner(),
+                $container->getMinMsiChecker(),
+                $consoleOutput,
+                $container->getMetricsCalculator(),
+                $container->getTestFrameworkExtraOptionsFilter()
+            );
+
             $engine->execute();
 
+            return true;
+        } catch (NoFilesInDiffToMutate $e) {
+            $io->success($e->getMessage());
+
             return true;
         } catch (InitialTestsFailed | MinMsiCheckFailed $exception) {
             // TODO: we can move that in a dedicated logger later and handle those cases in the

src/Logger/GitHub/NoFilesInDiffToMutate.php

@@ -0,0 +1,49 @@
+<?php
+/**
+ * This code is licensed under the BSD 3-Clause License.
+ *
+ * Copyright (c) 2017, 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\Logger\GitHub;
+
+use Exception;
+
+/**
+ * @internal
+ */
+final class NoFilesInDiffToMutate extends Exception
+{
+    public static function create(): self
+    {
+        return new self('No files in diff found, skipping mutation analysis.');
+    }
+}

tests/phpunit/Logger/GitHub/NoFilesInDiffToMutateTest.php

@@ -0,0 +1,53 @@
+<?php
+/**
+ * This code is licensed under the BSD 3-Clause License.
+ *
+ * Copyright (c) 2017, 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\Logger\GitHub;
+
+use Infection\Logger\GitHub\NoFilesInDiffToMutate;
+use PHPUnit\Framework\TestCase;
+
+final class NoFilesInDiffToMutateTest extends TestCase
+{
+    public function test_composer_not_found_exception(): void
+    {
+        $exception = NoFilesInDiffToMutate::create();
+
+        $this->assertInstanceOf(NoFilesInDiffToMutate::class, $exception);
+        $this->assertSame(
+            'No files in diff found, skipping mutation analysis.',
+            $exception->getMessage()
+        );
+    }
+}