local_variables needs to acquire properly encoded bytes to check their first

enebo · enebo · commit cee507ced1d0 · 2018-01-24T17:01:18.000-06:00
and last character to see if it is a local variable.

In truth, this is pretty weird code.  IdUtils only works with String and without
doubling the code for ByteList there is a weakness since non Java Charset
strings will not work here.  IdUtils itself is also pretty weird since we really
just want variables which are not special and this method checks for all sorts
of things we know these strings can never be.  (FIXME: added)
diff --git a/core/src/main/java/org/jruby/RubyKernel.java b/core/src/main/java/org/jruby/RubyKernel.java
@@ -767,15 +767,16 @@ public static RubyArray local_variables(ThreadContext context, IRubyObject recv)
     @JRubyMethod(name = "local_variables", module = true, visibility = PRIVATE, reads = SCOPE)
     public static RubyArray local_variables19(ThreadContext context, IRubyObject recv) {
         final Ruby runtime = context.runtime;
-        Set<ByteList> encounteredLocalVariables = new HashSet<>();
+        Set<RubySymbol> encounteredLocalVariables = new HashSet<>();
         RubyArray allLocalVariables = runtime.newArray();
         DynamicScope currentScope = context.getCurrentScope();
 
         while (currentScope != null) {
-            for (ByteList name : currentScope.getStaticScope().getByteVariables()) {
-                // FIXME: bytelist_love: Make charsetless checking of isLocal.
+            for (ByteList rawByteListName : currentScope.getStaticScope().getByteVariables()) {
+                RubySymbol name = runtime.newSymbol(rawByteListName);
+                // FIXME: Technically a non-charset String will still not work here.
                 if (IdUtil.isLocal(name.toString()) && !encounteredLocalVariables.contains(name)) {
-                    allLocalVariables.push(runtime.newSymbol(name));
+                    allLocalVariables.push(name);
                     encounteredLocalVariables.add(name);
                 }
             }
