Make locally clean without static locals (opt-in 4.1, banned in 4.2)

.hhconfig

@@ -7,3 +7,4 @@ disallow_destruct = true
 disallow_stringish_magic = true
 disable_primitive_refinement = true
 user_attributes=
+disable_static_local_variables = true

src/HHClientFallbackHandler.hack

@@ -9,6 +9,8 @@
 
 namespace Facebook\AutoloadMap;
 
+use namespace HH\Lib\C;
+
 /**
  * If a class/function/type isn't in the map, ask `hh_client` where it is.
  *
@@ -182,15 +184,16 @@ class HHClientFallbackHandler extends FailureHandler {
     $this->requireFile($file);
   }
 
+  static dict<string, ?string> $cache = dict[];
+
   private function lookupPath(string $kind, string $name): ?string {
-    static $cache = Map {};
     $key = $kind.'!'.$name;
-    if ($cache->containsKey($key)) {
-      return $cache[$key];
+    if (C\contains_key(static::$cache, $key)) {
+      return static::$cache[$key];
     }
 
     $path = $this->lookupPathImpl($kind, $name);
-    $cache[$key] = $path;
+    static::$cache[$key] = $path;
 
     if ($path === null) {
       return $path;

src/Writer.hack

@@ -224,14 +224,19 @@ function map(): \Facebook\AutoloadMap\AutoloadMap {
 
 } // Generated\
 
+namespace Facebook\AutoloadMap\_Private {
+  final class GlobalState {
+    public static bool \$initialized = false;
+  }
+}
+
 namespace Facebook\AutoloadMap {
 
 function initialize(): void {
-  static \$first_time = true;
-  if (!\$first_time) {
+  if (_Private\GlobalState::\$initialized) {
     return;
   }
-  \$first_time = false;
+  _Private\GlobalState::\$initialized = true;
   \$map = Generated\\map();
 
   \HH\autoload_set_paths(/* HH_FIXME[4110] */ \$map, Generated\\root());