Add notice to console output if actual msi is higher than required msi

src/Command/InfectionCommand.php

@@ -374,6 +374,14 @@ private function checkMetrics(): bool
             return false;
         }
 
+        if ($constraintChecker->isActualOverRequired()) {
+            $this->consoleOutput->logMinMsiCanGetIncreasedNotice(
+                $this->container['metrics'],
+                $constraintChecker->getMinRequiredValue(),
+                $constraintChecker->getActualOverRequiredType()
+            );
+        }
+
         $this->eventDispatcher->dispatch(new ApplicationExecutionFinished());
 
         return true;

src/Console/ConsoleOutput.php

@@ -35,6 +35,7 @@
 
 namespace Infection\Console;
 
+use Infection\Exception\InvalidTypeException;
 use Infection\Mutant\Exception\MsiCalculationException;
 use Infection\Mutant\MetricsCalculator;
 use Infection\Process\Runner\TestRunConstraintChecker;
@@ -47,6 +48,7 @@ final class ConsoleOutput
 {
     private const RUNNING_WITH_DEBUGGER_NOTE = 'You are running Infection with %s enabled.';
     private const CI_FLAG_ERROR = 'The minimum required %s percentage should be %s%%, but actual is %s%%. Improve your tests!';
+    private const MIN_MSI_CAN_GET_INCREASED_NOTICE = 'The %s is %s%% percent points over the required %s. Consider increasing the required %s percentage the next time you run infection.';
 
     /**
      * @var SymfonyStyle
@@ -87,6 +89,36 @@ public function logBadMsiErrorMessage(MetricsCalculator $metricsCalculator, floa
         );
     }
 
+    /**
+     * @throws InvalidTypeException
+     */
+    public function logMinMsiCanGetIncreasedNotice(MetricsCalculator $metricsCalculator, float $minMsi, string $type): void
+    {
+        if ($type !== TestRunConstraintChecker::MSI_OVER_MIN_MSI && $type !== TestRunConstraintChecker::COVERED_MSI_OVER_MIN_MSI) {
+            throw InvalidTypeException::create($type);
+        }
+
+        if ($type === TestRunConstraintChecker::MSI_OVER_MIN_MSI) {
+            $typeString = 'MSI';
+            $msi = $metricsCalculator->getMutationScoreIndicator();
+        } else {
+            $typeString = 'Covered Code MSI';
+            $msi = $metricsCalculator->getCoveredCodeMutationScoreIndicator();
+        }
+
+        $msiDifference = $msi - $minMsi;
+
+        $this->io->note(
+            sprintf(
+                self::MIN_MSI_CAN_GET_INCREASED_NOTICE,
+                $typeString,
+                $msiDifference,
+                $typeString,
+                $typeString
+            )
+        );
+    }
+
     public function logRunningWithDebugger(string $debugger): void
     {
         $this->io->writeln(sprintf(self::RUNNING_WITH_DEBUGGER_NOTE, $debugger));

src/Exception/InvalidTypeException.php

@@ -0,0 +1,51 @@
+<?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\Exception;
+
+use Exception;
+
+/**
+ * @internal
+ */
+final class InvalidTypeException extends Exception
+{
+    public static function create(string $type): self
+    {
+        return new self(
+            sprintf('Invalid type "%s" passed.', $type)
+        );
+    }
+}

src/Process/Runner/TestRunConstraintChecker.php

@@ -46,6 +46,12 @@ final class TestRunConstraintChecker
 
     public const COVERED_MSI_FAILURE = 'min-covered-msi';
 
+    public const MSI_OVER_MIN_MSI = 'msi-over-min-msi';
+
+    public const COVERED_MSI_OVER_MIN_MSI = 'covered-msi-over-min-msi';
+
+    private const VALUE_OVER_REQUIRED_TOLERANCE = 0.1;
+
     /**
      * @var MetricsCalculator
      */
@@ -71,6 +77,11 @@ final class TestRunConstraintChecker
      */
     private $failureType = '';
 
+    /**
+     * @var string
+     */
+    private $actualOverRequiredType = '';
+
     public function __construct(
         MetricsCalculator $metricsCalculator,
         bool $ignoreMsiWithNoMutations,
@@ -104,14 +115,38 @@ public function hasTestRunPassedConstraints(): bool
         return true;
     }
 
+    public function isActualOverRequired(): bool
+    {
+        if ($this->hasMsiOverRequired()) {
+            $this->actualOverRequiredType = self::MSI_OVER_MIN_MSI;
+
+            return true;
+        }
+
+        if ($this->hasCoveredMsiOverRequired()) {
+            $this->actualOverRequiredType = self::COVERED_MSI_OVER_MIN_MSI;
+
+            return true;
+        }
+
+        return false;
+    }
+
     public function getErrorType(): string
     {
         return $this->failureType;
     }
 
+    public function getActualOverRequiredType(): string
+    {
+        return $this->actualOverRequiredType;
+    }
+
     public function getMinRequiredValue(): float
     {
-        return $this->failureType === self::MSI_FAILURE ? $this->minMsi : $this->minCoveredMsi;
+        return
+            ($this->failureType === self::MSI_FAILURE || $this->actualOverRequiredType === self::MSI_OVER_MIN_MSI)
+            ? $this->minMsi : $this->minCoveredMsi;
     }
 
     private function hasBadMsi(): bool
@@ -123,4 +158,22 @@ private function hasBadCoveredMsi(): bool
     {
         return $this->minCoveredMsi && ($this->metricsCalculator->getCoveredCodeMutationScoreIndicator() < $this->minCoveredMsi);
     }
+
+    private function hasMsiOverRequired(): bool
+    {
+        if ($this->minMsi === 0.0) {
+            return false;
+        }
+
+        return $this->metricsCalculator->getMutationScoreIndicator() > $this->minMsi + self::VALUE_OVER_REQUIRED_TOLERANCE;
+    }
+
+    private function hasCoveredMsiOverRequired(): bool
+    {
+        if ($this->minCoveredMsi === 0.0) {
+            return false;
+        }
+
+        return $this->metricsCalculator->getCoveredCodeMutationScoreIndicator() > $this->minCoveredMsi + self::VALUE_OVER_REQUIRED_TOLERANCE;
+    }
 }

tests/phpunit/Console/ConsoleOutputTest.php

@@ -38,6 +38,7 @@
 use Infection\Console\ConsoleOutput;
 use Infection\Mutant\Exception\MsiCalculationException;
 use Infection\Mutant\MetricsCalculator;
+use Infection\Process\Runner\TestRunConstraintChecker;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Console\Style\SymfonyStyle;
 
@@ -123,4 +124,44 @@ public function test_log_not_in_control_of_exit_codes(): void
         $consoleOutput = new ConsoleOutput($io);
         $consoleOutput->logNotInControlOfExitCodes();
     }
+
+    public function test_log_min_msi_can_get_increased_notice_for_msi(): void
+    {
+        $actualMsi = 10.0;
+        $minMsi = 5.0;
+        $msiDifference = $actualMsi - $minMsi;
+
+        $io = $this->createMock(SymfonyStyle::class);
+        $io->expects($this->once())->method('note')
+            ->with(
+                'The MSI is ' . $msiDifference . '% percent points over the required MSI. ' .
+                'Consider increasing the required MSI percentage the next time you run infection.');
+        $metricsCalculator = $this->createMock(MetricsCalculator::class);
+
+        $metricsCalculator->expects($this->once())->method('getMutationScoreIndicator')
+            ->willReturn($actualMsi);
+
+        $consoleOutput = new ConsoleOutput($io);
+        $consoleOutput->logMinMsiCanGetIncreasedNotice($metricsCalculator, $minMsi, TestRunConstraintChecker::MSI_OVER_MIN_MSI);
+    }
+
+    public function test_log_min_msi_can_get_increased_notice_for_covered_msi(): void
+    {
+        $actualMsi = 10.0;
+        $minMsi = 5.0;
+        $msiDifference = $actualMsi - $minMsi;
+
+        $io = $this->createMock(SymfonyStyle::class);
+        $io->expects($this->once())->method('note')
+            ->with(
+                'The Covered Code MSI is ' . $msiDifference . '% percent points over the required Covered Code MSI. ' .
+                'Consider increasing the required Covered Code MSI percentage the next time you run infection.');
+        $metricsCalculator = $this->createMock(MetricsCalculator::class);
+
+        $metricsCalculator->expects($this->once())->method('getCoveredCodeMutationScoreIndicator')
+            ->willReturn($actualMsi);
+
+        $consoleOutput = new ConsoleOutput($io);
+        $consoleOutput->logMinMsiCanGetIncreasedNotice($metricsCalculator, $minMsi, TestRunConstraintChecker::COVERED_MSI_OVER_MIN_MSI);
+    }
 }

tests/phpunit/Exception/InvalidTypeExceptionTest.php

@@ -0,0 +1,54 @@
+<?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\Exception;
+
+use Infection\Exception\InvalidTypeException;
+use PHPUnit\Framework\TestCase;
+
+final class InvalidTypeExceptionTest extends TestCase
+{
+    public function test_it_has_correct_user_facing_message(): void
+    {
+        $type = 'FooType';
+
+        $exception = InvalidTypeException::create($type);
+
+        $this->assertSame(
+            'Invalid type "' . $type . '" passed.',
+            $exception->getMessage()
+        );
+    }
+}

tests/phpunit/Process/Runner/TestRunConstraintCheckerTest.php

@@ -35,6 +35,7 @@
 
 namespace Infection\Tests\Process\Runner;
 
+use Generator;
 use Infection\Mutant\MetricsCalculator;
 use Infection\Process\Runner\TestRunConstraintChecker;
 use PHPUnit\Framework\TestCase;
@@ -202,4 +203,63 @@ public function test_run_passes_on_exactly_covered_min_msi(): void
 
         $this->assertTrue($constraintChecker->hasTestRunPassedConstraints());
     }
+
+    /**
+     * @dataProvider isMsiOverMinimumMsiProvider
+     */
+    public function test_is_msi_over_minimum_msi_for_msi(?float $actualMsi, float $minMsi, bool $expected): void
+    {
+        $metrics = $this->createMock(MetricsCalculator::class);
+        $metrics->expects($this->once())->method('getMutationScoreIndicator')->willReturn($actualMsi);
+
+        $constraintChecker = new TestRunConstraintChecker(
+            $metrics,
+            false,
+            $minMsi,
+            0.0
+        );
+
+        $this->assertSame($expected, $constraintChecker->isActualOverRequired());
+    }
+
+    /**
+     * @dataProvider isMsiOverMinimumMsiProvider
+     */
+    public function test_is_msi_over_minimum_msi_for_covered_msi(float $actualCoveredMsi, float $minCoveredMsi, bool $expected): void
+    {
+        $metrics = $this->createMock(MetricsCalculator::class);
+        $metrics->expects($this->once())->method('getCoveredCodeMutationScoreIndicator')->willReturn($actualCoveredMsi);
+
+        $constraintChecker = new TestRunConstraintChecker(
+            $metrics,
+            false,
+            0.0,
+            $minCoveredMsi
+        );
+
+        $this->assertSame($expected, $constraintChecker->isActualOverRequired());
+    }
+
+    public function isMsiOverMinimumMsiProvider(): Generator
+    {
+        $minMsi = 10.0;
+
+        yield [
+            'actualMsi' => $minMsi + 1.0,
+            'minMsi' => $minMsi,
+            'expected' => true,
+        ];
+
+        yield [
+            'actualMsi' => $minMsi,
+            'minMsi' => $minMsi,
+            'expected' => false,
+        ];
+
+        yield [
+            'actualMsi' => $minMsi - 1.0,
+            'minMsi' => $minMsi,
+            'expected' => false,
+        ];
+    }
 }