Frozen string literals core files no exception dups (GR-12998).

PullRequest: truffleruby/498

Author: chrisseaton

CHANGELOG.md

@@ -28,6 +28,8 @@ Changes:
 Performance:
 
 * Sped up accesses to native memory through FFI::Pointer.
+* All core files now make use of frozen `String` literals, reducing the number
+  of `String` allocations for core methods.
 
 # 1.0 RC 10
 

src/main/java/org/truffleruby/parser/BodyTranslator.java

@@ -2880,13 +2880,10 @@ public RubyNode visitStrNode(StrParseNode node) {
         final Rope rope = context.getRopeCache().getRope(node.getValue(), node.getCodeRange());
         final RubyNode ret;
 
-        // isFrozen() is set with the magic frozen_string_literal comment or the command line flag.
-        // For the command line flag, we do not want to apply it to the core library files.
-        // TODO (eregon, 28 Feb 2018): we should respect the magic comment in core (although not used currently).
-        if (node.isFrozen() && !inCore()) {
+        if (node.isFrozen()) {
             final DynamicObject frozenString = context.getFrozenStringLiteral(rope);
 
-            ret = new DefinedWrapperNode(context.getCoreStrings().METHOD,
+            ret = new DefinedWrapperNode(context.getCoreStrings().EXPRESSION,
                     new ObjectLiteralNode(frozenString));
         } else {
             ret = new StringLiteralNode(rope);

src/main/ruby/core/argf.rb

@@ -1,4 +1,6 @@
-# Copyright (c) 2016, 2017 Oracle and/or its affiliates. All rights reserved. This
+# frozen_string_literal: true
+
+# Copyright (c) 2016, 2018 Oracle and/or its affiliates. All rights reserved. This
 # code is released under a tri EPL/GPL/LGPL license. You can use it,
 # redistribute it and/or modify it under the terms of the:
 #
@@ -568,7 +570,7 @@ def to_io
     # Returns "ARGF" as the string representation of this object.
     #
     def to_s
-      'ARGF'
+      +'ARGF'
     end
 
 
@@ -592,7 +594,7 @@ def advance!
         if @argv.empty?
           @advance = false
           @stream = $stdin
-          @filename = '-'
+          @filename = +'-'
           @use_stdin_only = true
           return true
         end

src/main/ruby/core/array.rb

@@ -1,4 +1,6 @@
-# Copyright (c) 2015, 2017 Oracle and/or its affiliates. All rights reserved. This
+# frozen_string_literal: true
+
+# Copyright (c) 2015, 2018 Oracle and/or its affiliates. All rights reserved. This
 # code is released under a tri EPL/GPL/LGPL license. You can use it,
 # redistribute it and/or modify it under the terms of the:
 #
@@ -604,11 +606,11 @@ def insert(idx, *items)
   Truffle::Graal.always_split instance_method(:insert)
 
   def inspect
-    return '[]'.force_encoding(Encoding::US_ASCII) if size == 0
+    return '[]'.encode(Encoding::US_ASCII) if size == 0
     comma = ', '
-    result = '['
+    result = +'['
 
-    return '[...]' if Thread.detect_recursion self do
+    return +'[...]' if Thread.detect_recursion self do
       each_with_index do |element, index|
         temp = Truffle::Type.rb_inspect(element)
         result.force_encoding(temp.encoding) if index == 0
@@ -624,9 +626,9 @@ def inspect
   alias_method :to_s, :inspect
 
   def join(sep=nil)
-    return ''.force_encoding(Encoding::US_ASCII) if size == 0
+    return ''.encode(Encoding::US_ASCII) if size == 0
 
-    out = ''
+    out = +''
     raise ArgumentError, 'recursive array join' if Thread.detect_recursion self do
       sep = sep.nil? ? $, : StringValue(sep)
 

src/main/ruby/core/basic_object.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2007-2015, Evan Phoenix and contributors
 # All rights reserved.
 #

src/main/ruby/core/binding.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2014, 2017 Oracle and/or its affiliates. All rights reserved. This
 # code is released under a tri EPL/GPL/LGPL license. You can use it,
 # redistribute it and/or modify it under the terms of the:

src/main/ruby/core/channel.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2015, 2017 Oracle and/or its affiliates. All rights reserved. This
 # code is released under a tri EPL/GPL/LGPL license. You can use it,
 # redistribute it and/or modify it under the terms of the:

src/main/ruby/core/class.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2007-2015, Evan Phoenix and contributors
 # All rights reserved.
 #

src/main/ruby/core/comparable.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2007-2015, Evan Phoenix and contributors
 # All rights reserved.
 #

src/main/ruby/core/complex.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright (c) 2007-2015, Evan Phoenix and contributors
 # All rights reserved.
 #