Implement caching for config file parsing to improve performance

.gitignore

@@ -67,3 +67,6 @@ spc.exe
 
 # dumped files from StaticPHP v3
 /dump-*.json
+
+# config parse cache
+/.spc.cache.php

src/StaticPHP/Config/ArtifactConfig.php

@@ -42,13 +42,22 @@ class ArtifactConfig
         if ($content === false) {
             throw new WrongUsageException("Failed to read artifact config file: {$file}");
         }
-        $data = match (pathinfo($file, PATHINFO_EXTENSION)) {
-            'json' => json_decode($content, true),
-            'yml', 'yaml' => Yaml::parse($content),
-            default => throw new WrongUsageException("Unsupported artifact config file format: {$file}"),
-        };
-        if (!is_array($data)) {
-            throw new WrongUsageException("Invalid JSON format in artifact config file: {$file}");
+        // use cache to skip redundant parsing
+        $data = ConfigCache::get($content);
+        if ($data !== null) {
+            logger()->debug("Config cache hit: {$file}");
+        } else {
+            $data = match (pathinfo($file, PATHINFO_EXTENSION)) {
+                'json' => json_decode($content, true),
+                'yml', 'yaml' => extension_loaded('yaml') ? yaml_parse($content) : Yaml::parse($content),
+                default => throw new WrongUsageException("Unsupported artifact config file format: {$file}"),
+            };
+            if (!is_array($data)) {
+                throw new WrongUsageException("Invalid JSON format in artifact config file: {$file}");
+            }
+            if (is_array($data)) {
+                ConfigCache::set($content, $data);
+            }
         }
         ConfigValidator::validateAndLintArtifacts(basename($file), $data);
         foreach ($data as $artifact_name => $config) {
@@ -68,6 +77,16 @@ class ArtifactConfig
         return self::$artifact_configs;
     }
 
+    /**
+     * Restore artifact configs from cache without re-parsing YAML files.
+     *
+     * @internal used by Registry cache layer only
+     */
+    public static function _restoreFromCache(array $configs): void
+    {
+        self::$artifact_configs = array_merge(self::$artifact_configs, $configs);
+    }
+
     /**
      * Get the configuration for a specific artifact by name.
      *

src/StaticPHP/Config/ConfigCache.php

@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace StaticPHP\Config;
+
+/**
+ * Simple parse-result cache for YAML/JSON config files.
+ *
+ * Key   = raw file content string (files are small, direct comparison is fine).
+ * Value = parsed PHP array.
+ *
+ * Storage: <cwd>/.spc.cache.php  (plain PHP, var_export'd array).
+ * Written once on shutdown when any new entry was added.
+ */
+class ConfigCache
+{
+    private static ?array $cache = null;
+
+    private static bool $dirty = false;
+
+    /**
+     * Return the cached parsed result for $content, or null on miss.
+     */
+    public static function get(string $content): ?array
+    {
+        self::load();
+        return self::$cache[$content] ?? null;
+    }
+
+    /**
+     * Store a parsed result. Will be persisted to disk on shutdown.
+     */
+    public static function set(string $content, array $data): void
+    {
+        self::load();
+        self::$cache[$content] = $data;
+        self::$dirty = true;
+    }
+
+    /**
+     * Write cache to disk if anything changed. Called automatically on shutdown.
+     */
+    public static function flush(): void
+    {
+        if (!self::$dirty) {
+            return;
+        }
+        file_put_contents(self::cachePath(), '<?php return ' . var_export(self::$cache, true) . ";\n");
+        self::$dirty = false;
+    }
+
+    private static function cachePath(): string
+    {
+        return getcwd() . '/.spc.cache.php';
+    }
+
+    private static function load(): void
+    {
+        if (self::$cache !== null) {
+            return;
+        }
+        $path = self::cachePath();
+        self::$cache = file_exists($path) ? (require $path) : [];
+        register_shutdown_function([self::class, 'flush']);
+    }
+}

src/StaticPHP/Config/PackageConfig.php

@@ -50,12 +50,20 @@ class PackageConfig
         if ($content === false) {
             throw new WrongUsageException("Failed to read package config file: {$file}");
         }
-        // judge extension
-        $data = match (pathinfo($file, PATHINFO_EXTENSION)) {
-            'json' => json_decode($content, true),
-            'yml', 'yaml' => Yaml::parse($content),
-            default => throw new WrongUsageException("Unsupported package config file format: {$file}"),
-        };
+        // judge extension — use cache to skip redundant parsing
+        $data = ConfigCache::get($content);
+        if ($data !== null) {
+            logger()->debug("Config cache hit: {$file}");
+        } else {
+            $data = match (pathinfo($file, PATHINFO_EXTENSION)) {
+                'json' => json_decode($content, true),
+                'yml', 'yaml' => extension_loaded('yaml') ? yaml_parse($content) : Yaml::parse($content),
+                default => throw new WrongUsageException("Unsupported package config file format: {$file}"),
+            };
+            if (is_array($data)) {
+                ConfigCache::set($content, $data);
+            }
+        }
         ConfigValidator::validateAndLintPackages(basename($file), $data);
         foreach ($data as $pkg_name => $config) {
             self::$package_configs[$pkg_name] = $config;

src/StaticPHP/Registry/Registry.php

@@ -64,7 +64,7 @@ class Registry
         }
         $data = match (pathinfo($registry_file, PATHINFO_EXTENSION)) {
             'json' => json_decode($yaml, true),
-            'yaml', 'yml' => Yaml::parse($yaml),
+            'yaml', 'yml' => extension_loaded('yaml') ? yaml_parse($yaml) : Yaml::parse($yaml),
             default => throw new RegistryException("Unsupported registry file format: {$registry_file}"),
         };
         if (!is_array($data)) {