feat: adds snapshot testing

src/Repositories/SnapshotRepository.php

@@ -0,0 +1,133 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Repositories;
+
+use Pest\Exceptions\ShouldNotHappen;
+use Pest\Support\Str;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ */
+final class SnapshotRepository
+{
+    /**
+     * Creates a snapshot repository instance.
+     */
+    public function __construct(
+        readonly private string $testsPath,
+        readonly private string $snapshotsPath,
+    ) {
+    }
+
+    /**
+     * Checks if the snapshot exists.
+     */
+    public function has(TestCase $testCase, string $description): bool
+    {
+        [$filename, $description] = $this->getFilenameAndDescription($testCase);
+
+        return file_exists($this->getSnapshotFilename($filename, $description));
+    }
+
+    /**
+     * Gets the snapshot.
+     *
+     * @return array{0: string, 1: string}
+     *
+     * @throws ShouldNotHappen
+     */
+    public function get(TestCase $testCase, string $description): array
+    {
+        [$filename, $description] = $this->getFilenameAndDescription($testCase);
+
+        $contents = file_get_contents($snapshotFilename = $this->getSnapshotFilename($filename, $description));
+
+        if ($contents === false) {
+            throw ShouldNotHappen::fromMessage('Snapshot file could not be read.');
+        }
+
+        return [$snapshotFilename, $contents];
+    }
+
+    /**
+     * Saves the given snapshot for the given test case.
+     */
+    public function save(TestCase $testCase, string $snapshot): string
+    {
+        [$filename, $description] = $this->getFilenameAndDescription($testCase);
+
+        $snapshotFilename = $this->getSnapshotFilename($filename, $description);
+
+        if (! file_exists(dirname($snapshotFilename))) {
+            mkdir(dirname($snapshotFilename), 0755, true);
+        }
+
+        file_put_contents($snapshotFilename, $snapshot);
+
+        return str_replace(dirname($this->testsPath).'/', '', $snapshotFilename);
+    }
+
+    /**
+     * Flushes the snapshots.
+     */
+    public function flush(): void
+    {
+        $absoluteSnapshotsPath = $this->testsPath.'/'.$this->snapshotsPath;
+
+        $deleteDirectory = function (string $path) use (&$deleteDirectory): void {
+            if (file_exists($path)) {
+                $scannedDir = scandir($path);
+                assert(is_array($scannedDir));
+
+                $files = array_diff($scannedDir, ['.', '..']);
+
+                foreach ($files as $file) {
+                    if (is_dir($path.'/'.$file)) {
+                        $deleteDirectory($path.'/'.$file);
+                    } else {
+                        unlink($path.'/'.$file);
+                    }
+                }
+
+                rmdir($path);
+            }
+        };
+
+        if (file_exists($absoluteSnapshotsPath)) {
+            $deleteDirectory($absoluteSnapshotsPath);
+        }
+    }
+
+    /**
+     * Gets the snapshot's "filename" and "description".
+     *
+     * @return array{0: string, 1: string}
+     */
+    private function getFilenameAndDescription(TestCase $testCase): array
+    {
+        $filename = (fn () => self::$__filename)->call($testCase, $testCase::class); // @phpstan-ignore-line
+
+        $description = str_replace('__pest_evaluable_', '', $testCase->name());
+        $datasetAsString = str_replace('__pest_evaluable_', '', Str::evaluable($testCase->dataSetAsStringWithData()));
+
+        $description = str_replace(' ', '_', $description.$datasetAsString);
+
+        return [$filename, $description];
+    }
+
+    /**
+     * Gets the snapshot's "filename".
+     */
+    private function getSnapshotFilename(string $filename, string $description): string
+    {
+        $relativePath = str_replace($this->testsPath, '', $filename);
+
+        // remove extension from filename
+        $relativePath = substr($relativePath, 0, (int) strrpos($relativePath, '.'));
+
+        return sprintf('%s/%s.snap', $this->testsPath.'/'.$this->snapshotsPath.$relativePath, $description);
+    }
+}