Extract modifier mapping to utility class

See #184 (review)

Author: thekid

src/main/php/lang/ast/emit/AsymmetricVisibility.class.php

@@ -20,24 +20,8 @@ trait AsymmetricVisibility {
   use VisibilityChecks;
 
   protected function emitProperty($result, $property) {
-    static $lookup= [
-      'public'         => MODIFIER_PUBLIC,
-      'protected'      => MODIFIER_PROTECTED,
-      'private'        => MODIFIER_PRIVATE,
-      'static'         => MODIFIER_STATIC,
-      'final'          => MODIFIER_FINAL,
-      'abstract'       => MODIFIER_ABSTRACT,
-      'readonly'       => MODIFIER_READONLY,
-      'public(set)'    => 0x1000000,
-      'protected(set)' => 0x0000800,
-      'private(set)'   => 0x0001000,
-    ];
-
     $scope= $result->codegen->scope[0];
-    $modifiers= 0;
-    foreach ($property->modifiers as $name) {
-      $modifiers|= $lookup[$name];
-    }
+    $modifiers= Modifiers::bits($property->modifiers);
 
     // Declare checks for private(set) and protected(set), folding declarations
     // like `[visibility] [visibility](set)` to just the visibility itself.

src/main/php/lang/ast/emit/FinalProperties.class.php

@@ -1,24 +1,16 @@
 <?php namespace lang\ast\emit;
 
+/**
+ * When property hooks were introduced into PHP 8.4, it also added a mechanism
+ * for properties to be declared as final. For other PHP versions, emit without
+ * final modifier, store `final` in xp::$meta
+ *
+ * @see  https://wiki.php.net/rfc/property-hooks
+ * @test lang.ast.unittest.emit.MembersTest
+ */
 trait FinalProperties {
 
   protected function emitProperty($result, $property) {
-    static $lookup= [
-      'public'    => MODIFIER_PUBLIC,
-      'protected' => MODIFIER_PROTECTED,
-      'private'   => MODIFIER_PRIVATE,
-      'static'    => MODIFIER_STATIC,
-      'final'     => MODIFIER_FINAL,
-      'abstract'  => MODIFIER_ABSTRACT,
-      'readonly'  => 0x0080, // XP 10.13: MODIFIER_READONLY
-    ];
-
-    $modifiers= 0;
-    foreach ($property->modifiers as $name) {
-      $modifiers|= $lookup[$name];
-    }
-
-    // Emit without final modifier, store `final` in xp::$meta
     $property->modifiers= array_diff($property->modifiers, ['final']);
     parent::emitProperty($result, $property);
     $result->codegen->scope[0]->meta[self::PROPERTY][$property->name][DETAIL_ARGUMENTS]= [MODIFIER_FINAL];

src/main/php/lang/ast/emit/Modifiers.class.php

@@ -0,0 +1,30 @@
+<?php namespace lang\ast\emit;
+
+class Modifiers {
+  const LOOKUP= [
+    'public'         => MODIFIER_PUBLIC,
+    'protected'      => MODIFIER_PROTECTED,
+    'private'        => MODIFIER_PRIVATE,
+    'static'         => MODIFIER_STATIC,
+    'final'          => MODIFIER_FINAL,
+    'abstract'       => MODIFIER_ABSTRACT,
+    'readonly'       => 0x0080,    // XP 10.13: MODIFIER_READONLY
+    'public(set)'    => 0x1000000,
+    'protected(set)' => 0x0000800,
+    'private(set)'   => 0x0001000,
+  ];
+
+  /**
+   * Converts modifiers to a bit set
+   *
+   * @param  string[] $modifiers
+   * @return int
+   */
+  public static function bits($modifiers) {
+    $bits= 0;
+    foreach ($modifiers as $name) {
+      $bits|= self::LOOKUP[$name];
+    }
+    return $bits;
+  }
+}

src/main/php/lang/ast/emit/PropertyHooks.class.php

@@ -71,25 +71,8 @@ protected function withScopeCheck($modifiers, $nodes) {
   }
 
   protected function emitProperty($result, $property) {
-    static $lookup= [
-      'public'         => MODIFIER_PUBLIC,
-      'protected'      => MODIFIER_PROTECTED,
-      'private'        => MODIFIER_PRIVATE,
-      'static'         => MODIFIER_STATIC,
-      'final'          => MODIFIER_FINAL,
-      'abstract'       => MODIFIER_ABSTRACT,
-      'readonly'       => MODIFIER_READONLY,
-      'public(set)'    => 0x1000000,
-      'protected(set)' => 0x0000800,
-      'private(set)'   => 0x0001000,
-    ];
-
-    // Emit XP meta information for the reflection API
     $scope= $result->codegen->scope[0];
-    $modifiers= 0;
-    foreach ($property->modifiers as $name) {
-      $modifiers|= $lookup[$name];
-    }
+    $modifiers= Modifiers::bits($property->modifiers);
 
     // Derive modifiers for private(set) and protected(set), folding declarations
     // like `[visibility] [visibility](set)` to just the visibility itself.

src/main/php/lang/ast/emit/ReadonlyProperties.class.php

@@ -22,23 +22,10 @@ trait ReadonlyProperties {
   use VisibilityChecks;
 
   protected function emitProperty($result, $property) {
-    static $lookup= [
-      'public'    => MODIFIER_PUBLIC,
-      'protected' => MODIFIER_PROTECTED,
-      'private'   => MODIFIER_PRIVATE,
-      'static'    => MODIFIER_STATIC,
-      'final'     => MODIFIER_FINAL,
-      'abstract'  => MODIFIER_ABSTRACT,
-      'readonly'  => 0x0080, // XP 10.13: MODIFIER_READONLY
-    ];
-
     if (!in_array('readonly', $property->modifiers)) return parent::emitProperty($result, $property);
 
     $scope= $result->codegen->scope[0];
-    $modifiers= 0;
-    foreach ($property->modifiers as $name) {
-      $modifiers|= $lookup[$name];
-    }
+    $modifiers= Modifiers::bits($property->modifiers);
     $scope->meta[self::PROPERTY][$property->name]= [
       DETAIL_RETURNS     => $property->type ? $property->type->name() : 'var',
       DETAIL_ANNOTATIONS => $property->annotations,