Merge pull request #94 from mathieutu/feat/no-create-snapshots

Add the ability to disable snapshots creation.

Author: sebastiandedeyne

README.md

@@ -274,13 +274,29 @@ Drivers can be used by passing them as `assertMatchesSnapshot`'s second argument
 $this->assertMatchesSnapshot($something->toYaml(), new MyYamlDriver());
 ```
 
+### Usage in CI
+
+When running your tests in Continuous Integration you would possibly want to disable the creation of snapshots.
+
+By using the `--no-create-snapshots` parameter, PHPUnit will fail if the snapshots don't exist.
+
+```bash
+> ./vendor/bin/phpunit -d --no-create-snapshots
+
+1) ExampleTest::test_it_matches_a_string
+Snapshot "ExampleTest__test_it_matches_a_string__1.txt" does not exist. 
+You can automatically create it by removing `-d --no-create-snapshots` of PHPUnit's CLI arguments.
+
+```
+
+
 ## Changelog
 
 Please see [CHANGELOG](CHANGELOG.md) for more information what has changed recently.
 
 ## Testing
 
-``` bash
+```bash
 composer test
 ```
 

composer.json

@@ -26,7 +26,10 @@
         "phpunit/phpunit": "^8.3|^9.0",
         "symfony/property-access": "^4.0|^5.0",
         "symfony/serializer": "^4.0|^5.0",
-        "symfony/yaml": "^4.0|^5.0",
+        "symfony/yaml": "^4.0|^5.0"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^9.1.0"
     },
     "autoload": {
         "psr-4": {

src/MatchesSnapshots.php

@@ -2,15 +2,15 @@
 
 namespace Spatie\Snapshots;
 
+use PHPUnit\Framework\ExpectationFailedException;
 use ReflectionClass;
 use ReflectionObject;
-use Spatie\Snapshots\Drivers\XmlDriver;
 use Spatie\Snapshots\Drivers\HtmlDriver;
 use Spatie\Snapshots\Drivers\JsonDriver;
+use Spatie\Snapshots\Drivers\ObjectDriver;
 use Spatie\Snapshots\Drivers\TextDriver;
+use Spatie\Snapshots\Drivers\XmlDriver;
 use Spatie\Snapshots\Drivers\YamlDriver;
-use Spatie\Snapshots\Drivers\ObjectDriver;
-use PHPUnit\Framework\ExpectationFailedException;
 
 trait MatchesSnapshots
 {
@@ -152,6 +152,18 @@ protected function shouldUpdateSnapshots(): bool
         return in_array('--update-snapshots', $_SERVER['argv'], true);
     }
 
+    /*
+     * Determines whether or not the snapshot should be created instead of
+     * matched.
+     *
+     * Override this method if you want to use a different flag or mechanism
+     * than `-d --without-creating-snapshots`.
+     */
+    protected function shouldCreateSnapshots(): bool
+    {
+        return ! in_array('--without-creating-snapshots', $_SERVER['argv'], true);
+    }
+
     protected function doSnapshotAssertion($actual, Driver $driver)
     {
         $this->snapshotIncrementor++;
@@ -163,6 +175,8 @@ protected function doSnapshotAssertion($actual, Driver $driver)
         );
 
         if (! $snapshot->exists()) {
+            $this->assertSnapshotShouldBeCreated($snapshot->filename());
+
             $this->createSnapshotAndMarkTestIncomplete($snapshot, $actual);
         }
 
@@ -231,6 +245,8 @@ protected function doFileSnapshotAssertion(string $filePath): void
         }
 
         if (! $fileSystem->has($snapshotId)) {
+            $this->assertSnapshotShouldBeCreated($failedSnapshotId);
+
             $fileSystem->copy($filePath, $snapshotId);
 
             $this->registerSnapshotChange("File snapshot created for {$snapshotId}");
@@ -288,4 +304,17 @@ protected function registerSnapshotChange(string $message): void
     {
         $this->snapshotChanges[] = $message;
     }
+
+    protected function assertSnapshotShouldBeCreated(string $snapshotFileName): void
+    {
+        if ($this->shouldCreateSnapshots()) {
+            return;
+        }
+
+        $this->fail(
+            "Snapshot \"$snapshotFileName\" does not exist.\n".
+            'You can automatically create it by removing '.
+            '`-d --without-creating-snapshots` of PHPUnit\'s CLI arguments.'
+        );
+    }
 }

tests/Integration/MatchesSnapshotTest.php

@@ -2,6 +2,7 @@
 
 namespace Spatie\Snapshots\Test\Integration;
 
+use PHPUnit\Framework\AssertionFailedError;
 use PHPUnit\Framework\ExpectationFailedException;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
@@ -18,10 +19,15 @@ public function setUp(): void
         $this->setUpComparesSnapshotFiles();
 
         $updateArgument = array_search('--update-snapshots', $_SERVER['argv']);
+        $withoutCreatingArgument = array_search('--without-creating-snapshots', $_SERVER['argv']);
 
         if ($updateArgument) {
             unset($_SERVER['argv'][$updateArgument]);
         }
+
+        if ($withoutCreatingArgument) {
+            unset($_SERVER['argv'][$withoutCreatingArgument]);
+        }
     }
 
     /** @test */
@@ -209,7 +215,10 @@ public function it_can_mismatch_a_file_snapshot()
     {
         $mockTrait = $this->getMatchesSnapshotMock();
 
-        $this->expectFail($mockTrait);
+        $this->expectFail(
+            $mockTrait,
+            'File did not match snapshot (MatchesSnapshotTest__it_can_mismatch_a_file_snapshot__1.jpg)'
+        );
 
         $mockTrait->assertMatchesFileSnapshot(__DIR__.'/stubs/test_files/troubled_man.jpg');
     }
@@ -219,7 +228,10 @@ public function it_can_mismatch_a_file_snapshot_with_a_different_extension()
     {
         $mockTrait = $this->getMatchesSnapshotMock();
 
-        $this->expectFail($mockTrait);
+        $this->expectFail(
+            $mockTrait,
+            'File did not match the snapshot file extension (expected: jpg, was: png)'
+        );
 
         $mockTrait->assertMatchesFileSnapshot(__DIR__.'/stubs/test_files/no_man.png');
     }
@@ -229,10 +241,14 @@ public function it_needs_a_file_extension_to_do_a_file_snapshot_assertion()
     {
         $mockTrait = $this->getMatchesSnapshotMock();
 
-        $this->expectFail($mockTrait);
-
         $filePath = __DIR__.'/stubs/test_files/file_without_extension';
 
+        $this->expectFail(
+            $mockTrait,
+            'Unable to make a file snapshot, file does not have a file extension '.
+            "($filePath)"
+        );
+
         $this->assertFileExists($filePath);
 
         $mockTrait->assertMatchesFileSnapshot($filePath);
@@ -243,7 +259,10 @@ public function it_persists_the_failed_file_after_mismatching_a_file_snapshot()
     {
         $mockTrait = $this->getMatchesSnapshotMock();
 
-        $this->expectFail($mockTrait);
+        $this->expectFail(
+            $mockTrait,
+            'File did not match snapshot (MatchesSnapshotTest__it_persists_the_failed_file_after_mismatching_a_file_snapshot__1.jpg)'
+        );
 
         $mismatchedFile = __DIR__.'/stubs/test_files/troubled_man.jpg';
 
@@ -270,7 +289,7 @@ public function it_deletes_the_persisted_failed_file_before_a_file_snapshot_asse
 
         $mockTrait->assertMatchesFileSnapshot(__DIR__.'/stubs/test_files/friendly_man.jpg');
 
-        $this->assertFileNotExists($persistedFailedFile);
+        $this->assertFileDoesNotExist($persistedFailedFile);
     }
 
     /** @test */
@@ -378,7 +397,7 @@ public function it_can_update_a_file_snapshot_with_a_different_extension()
             'file.png'
         );
 
-        $this->assertFileNotExists($oldSnapshot);
+        $this->assertFileDoesNotExist($oldSnapshot);
     }
 
     private function expectIncompleteMatchesSnapshotTest(MockObject $matchesSnapshotMock, callable $assertions)
@@ -392,11 +411,15 @@ private function expectIncompleteMatchesSnapshotTest(MockObject $matchesSnapshot
         $matchesSnapshotMock->markTestIncompleteIfSnapshotsHaveChanged();
     }
 
-    private function expectFail(MockObject $matchesSnapshotMock)
+    private function expectFail(MockObject $matchesSnapshotMock, string $message)
     {
+        $this->expectException(AssertionFailedError::class);
+
         $matchesSnapshotMock
             ->expects($this->once())
-            ->method('fail');
+            ->method('fail')
+            ->with($message)
+            ->willThrowException(new AssertionFailedError());
     }
 
     private function expectFailedMatchesSnapshotTest()
@@ -441,4 +464,36 @@ private function getMatchesSnapshotMock(): MockObject
 
         return $matchesSnapshotMock;
     }
+
+    /** @test */
+    public function it_doesnt_create_a_regular_snapshot_and_mismatches_if_asked()
+    {
+        $_SERVER['argv'][] = '--without-creating-snapshots';
+
+        $mockTrait = $this->getMatchesSnapshotMock();
+
+        $this->expectFail(
+            $mockTrait,
+            "Snapshot \"MatchesSnapshotTest__it_doesnt_create_a_regular_snapshot_and_mismatches_if_asked__1.txt\" does not exist.\n".
+            'You can automatically create it by removing `-d --without-creating-snapshots` of PHPUnit\'s CLI arguments.'
+        );
+
+        $mockTrait->assertMatchesSnapshot('Bar');
+    }
+
+    /** @test */
+    public function it_doesnt_create_a_file_snapshot_and_mismatches_if_asked()
+    {
+        $_SERVER['argv'][] = '--without-creating-snapshots';
+
+        $mockTrait = $this->getMatchesSnapshotMock();
+
+        $this->expectFail(
+            $mockTrait,
+            "Snapshot \"MatchesSnapshotTest__it_doesnt_create_a_file_snapshot_and_mismatches_if_asked__1.jpg_failed.jpg\" does not exist.\n".
+            'You can automatically create it by removing `-d --without-creating-snapshots` of PHPUnit\'s CLI arguments.'
+        );
+
+        $mockTrait->assertMatchesFileSnapshot(__DIR__.'/stubs/test_files/friendly_man.jpg');
+    }
 }