Fix ENV#clone and ENV#dup and raise TypeError

Author: andrykonchin

CHANGELOG.md

@@ -32,6 +32,7 @@ Compatibility:
 * Make `Coverage.start` and `Coverage.result` accept parameters (#3149, @mtortonesi, @andrykonchin).
 * Implement `rb_check_funcall()` (@eregon).
 * Implement `MatchData#{byteoffset,deconstruct,deconstruct_keys}` from Ruby 3.2 (#3039, @rwstauner).
+* Fix `ENV#{clone,dup}` and raise `TypeError` (#3039, @andrykonchin).
 
 Performance:
 

spec/tags/core/env/clone_tags.txt

@@ -78,6 +78,10 @@ def []=(key, value)
   end
   alias_method :store, :[]=
 
+  def clone
+    raise TypeError, 'Cannot clone ENV, use ENV.to_h to get a copy of ENV as a hash'
+  end
+
   def delete(key)
     existing_value = lookup(key)
     if existing_value
@@ -89,6 +93,10 @@ def delete(key)
     existing_value
   end
 
+  def dup
+    raise TypeError, 'Cannot dup ENV, use ENV.to_h to get a copy of ENV as a hash'
+  end
+
   def shift
     key = @variables.first
     return nil unless key