Remove explicit cloning of exception messages from core files.

Semantically, these messages shouldn't be frozen. In practice, it's very unlikely someone will try to mutate an exception's message. In order to clean up the source code, the explicit `+` calls are removed. If this turns out to be problematic, we can look at implicitly adding them back in when building the AST.

Author: nirvdrum

src/main/ruby/core/argf.rb

@@ -213,7 +213,7 @@ def eof?
     #         multiple FDs and if so, is this correct? --rue
     #
     def fileno
-      raise ArgumentError, +'No stream' unless advance!
+      raise ArgumentError, 'No stream' unless advance!
       @stream.fileno
     end
     alias_method :to_i, :fileno
@@ -327,7 +327,7 @@ def lineno=(val)
     # @see IO#pos.
     #
     def pos
-      raise ArgumentError, +'no stream' unless advance!
+      raise ArgumentError, 'no stream' unless advance!
       @stream.tell
     end
     alias_method :tell, :pos
@@ -338,7 +338,7 @@ def pos
     # @see IO#pos=
     #
     def pos=(position)
-      raise ArgumentError, +'no stream' unless advance!
+      raise ArgumentError, 'no stream' unless advance!
       @stream.pos = position
     end
 
@@ -357,7 +357,7 @@ def readbyte
         return val
       end
 
-      raise EOFError, +'ARGF at end'
+      raise EOFError, 'ARGF at end'
     end
     alias_method :readchar, :readbyte
 
@@ -469,13 +469,13 @@ def read_nonblock(bytes, output=nil, exception: true)
     # @see  #gets
     #
     def readline(sep=$/)
-      raise EOFError, +'ARGF at end' unless advance!
+      raise EOFError, 'ARGF at end' unless advance!
 
       if line = gets(sep)
         return line
       end
 
-      raise EOFError, +'ARGF at end'
+      raise EOFError, 'ARGF at end'
     end
 
     #
@@ -507,7 +507,7 @@ def readlines(sep=$/)
     # @todo Is this correct, only current stream is rewound? --rue
     #
     def rewind
-      raise ArgumentError, +'no stream to rewind' unless advance!
+      raise ArgumentError, 'no stream to rewind' unless advance!
       @lineno -= @stream.lineno
       @stream.rewind
     end
@@ -518,7 +518,7 @@ def rewind
     # @see IO#seek.
     #
     def seek(*args)
-      raise ArgumentError, +'no stream' unless advance!
+      raise ArgumentError, 'no stream' unless advance!
       @stream.seek(*args)
     end
 

src/main/ruby/core/array.rb

@@ -261,7 +261,7 @@ def bsearch_index
       when false, nil
         min = i + 1
       else
-        raise TypeError, +'wrong argument type (must be numeric, true, false or nil)'
+        raise TypeError, 'wrong argument type (must be numeric, true, false or nil)'
       end
 
       i = min + (max - min) / 2
@@ -426,13 +426,13 @@ def fetch(idx, default=undefined)
 
     if block_given?
       unless undefined.equal?(c)
-        raise ArgumentError, +'wrong number of arguments'
+        raise ArgumentError, 'wrong number of arguments'
       end
       one = a
       two = b
     else
       if undefined.equal?(a)
-        raise ArgumentError, +'wrong number of arguments'
+        raise ArgumentError, 'wrong number of arguments'
       end
       obj = a
       one = b
@@ -443,7 +443,7 @@ def fetch(idx, default=undefined)
       left = 0
       right = size
     elsif one.kind_of? Range
-      raise TypeError, +'length invalid with range' unless undefined.equal?(two)
+      raise TypeError, 'length invalid with range' unless undefined.equal?(two)
 
       left = Truffle::Type.coerce_to_collection_length one.begin
       left += size if left < 0
@@ -463,9 +463,9 @@ def fetch(idx, default=undefined)
         begin
           right = Truffle::Type.coerce_to_collection_length two
         rescue ArgumentError
-          raise RangeError, +'bignum too big to convert into `long'
+          raise RangeError, 'bignum too big to convert into `long'
         rescue TypeError
-          raise ArgumentError, +'second argument must be an Integer'
+          raise ArgumentError, 'second argument must be an Integer'
         end
 
         return self if right == 0
@@ -476,7 +476,7 @@ def fetch(idx, default=undefined)
     end
 
     unless Truffle::Type.fits_into_long?(left) && Truffle::Type.fits_into_long?(right)
-      raise ArgumentError, +'argument too big'
+      raise ArgumentError, 'argument too big'
     end
 
     i = left
@@ -499,7 +499,7 @@ def first(n = undefined)
     return at(0) if undefined.equal?(n)
 
     n = Truffle::Type.coerce_to_collection_index(n)
-    raise ArgumentError, +'Size must be positive' if n < 0
+    raise ArgumentError, 'Size must be positive' if n < 0
 
     Array.new self[0, n]
   end
@@ -629,7 +629,7 @@ def join(sep=nil)
     return ''.encode(Encoding::US_ASCII) if size == 0
 
     out = +''
-    raise ArgumentError, +'recursive array join' if Thread.detect_recursion self do
+    raise ArgumentError, 'recursive array join' if Thread.detect_recursion self do
       sep = sep.nil? ? $, : StringValue(sep)
 
       # We've manually unwound the first loop entry for performance
@@ -689,7 +689,7 @@ def last(n=undefined)
     n = Truffle::Type.coerce_to_collection_index n
     return [] if n == 0
 
-    raise ArgumentError, +'count must be positive' if n < 0
+    raise ArgumentError, 'count must be positive' if n < 0
 
     n = size if n > size
     Array.new self[-n..-1]
@@ -793,7 +793,7 @@ def product(*args)
     sum = args.inject(size) { |n, x| n * x.size }
 
     unless Truffle.invoke_primitive(:integer_fits_into_long, sum)
-      raise RangeError, +'product result is too large'
+      raise RangeError, 'product result is too large'
     end
 
     # TODO rewrite this to not use a tree of Proc objects.
@@ -991,8 +991,8 @@ def initialize(rng)
 
     def rand(size)
       random = Truffle::Type.coerce_to_collection_index @rng.rand(size)
-      raise RangeError, +'random value must be >= 0' if random < 0
-      raise RangeError, +'random value must be less than Array size' unless random < size
+      raise RangeError, 'random value must be >= 0' if random < 0
+      raise RangeError, 'random value must be less than Array size' unless random < size
 
       random
     end
@@ -1015,7 +1015,7 @@ def sample(count=undefined, options=undefined)
     end
 
     if count and count < 0
-      raise ArgumentError, +'count must be greater than 0'
+      raise ArgumentError, 'count must be greater than 0'
     end
 
     rng = options[:random] if options
@@ -1140,7 +1140,7 @@ def shuffle!(options = undefined)
 
   def drop(n)
     n = Truffle::Type.coerce_to_collection_index n
-    raise ArgumentError, +'attempt to drop negative size' if n < 0
+    raise ArgumentError, 'attempt to drop negative size' if n < 0
 
     new_size = size - n
     return [] if new_size <= 0
@@ -1183,7 +1183,7 @@ def transpose
       max ||= ary.size
 
       # Catches too-large as well as too-small (for which #fetch would suffice)
-      raise IndexError, +'All arrays must be same length' if ary.size != max
+      raise IndexError, 'All arrays must be same length' if ary.size != max
 
       ary.size.times do |i|
         entry = (out[i] ||= [])
@@ -1307,7 +1307,7 @@ def recursively_flatten(array, out, max_levels = -1)
       end
     end
 
-    raise ArgumentError, +'tried to flatten recursive array' if recursion
+    raise ArgumentError, 'tried to flatten recursive array' if recursion
     modified
   end
   private :recursively_flatten
@@ -1504,7 +1504,7 @@ def isort_block!(left, right, block)
         block_result = block.call(el1, el2)
 
         if block_result.nil?
-          raise ArgumentError, +'block returned nil'
+          raise ArgumentError, 'block returned nil'
         elsif block_result > 0
           self[j] = el1
           self[j - 1] = el2

src/main/ruby/core/complex.rb

@@ -58,7 +58,7 @@ class Complex < Numeric
 
   def self.convert(real, imag = undefined)
     if nil.equal?(real) || nil.equal?(imag)
-      raise TypeError, +'cannot convert nil into Complex'
+      raise TypeError, 'cannot convert nil into Complex'
     end
     imag = nil if undefined.equal?(imag)
 
@@ -105,13 +105,13 @@ def Complex.generic?(other) # :nodoc:
   end
 
   def Complex.rect(real, imag=0)
-    raise TypeError, +'not a real' unless check_real?(real) && check_real?(imag)
+    raise TypeError, 'not a real' unless check_real?(real) && check_real?(imag)
     new(real, imag)
   end
   class << self; alias_method :rectangular, :rect end
 
   def Complex.polar(r, theta=0)
-    raise TypeError, +'not a real' unless check_real?(r) && check_real?(theta)
+    raise TypeError, 'not a real' unless check_real?(r) && check_real?(theta)
 
     Complex(r*Math.cos(theta), r*Math.sin(theta))
   end

src/main/ruby/core/configuration.rb

@@ -35,7 +35,7 @@ def initialize
 
     def get_variable(name)
       Truffle.primitive :vm_get_config_item
-      raise PrimitiveFailure, +'Truffle::Configuration#get_variable primitive failed'
+      raise PrimitiveFailure, 'Truffle::Configuration#get_variable primitive failed'
     end
 
     def section(section, &block)

src/main/ruby/core/dir.rb

@@ -58,7 +58,7 @@ def initialize(path, options=undefined)
   end
 
   private def ensure_open
-    raise IOError, +'closed directory' if closed?
+    raise IOError, 'closed directory' if closed?
   end
 
   def fileno

src/main/ruby/core/dir_glob.rb

@@ -132,7 +132,7 @@ def call(matches, start)
 
     class StartRecursiveDirectories < Node
       def call(matches, start)
-        raise(+'invalid usage') if start
+        raise 'invalid usage' if start
 
         # Even though the recursive entry is zero width
         # in this case, its left separator is still the

src/main/ruby/core/encoding.rb

@@ -120,7 +120,7 @@ class << self
   end
 
   def self.default_external=(enc)
-    raise ArgumentError, +'default external encoding cannot be nil' if enc.nil?
+    raise ArgumentError, 'default external encoding cannot be nil' if enc.nil?
 
     enc = find(enc)
     set_alias_index 'external', enc

src/main/ruby/core/enumerable.rb

@@ -34,7 +34,7 @@
 module Enumerable
   def chunk(&original_block)
     initial_state = nil
-    raise ArgumentError, +'no block given' unless block_given?
+    raise ArgumentError, 'no block given' unless block_given?
     Enumerator.new do |yielder|
       previous = nil
       accumulate = []
@@ -55,7 +55,7 @@ def chunk(&original_block)
           when :_alone
             yielder.yield [key, [val]]
           else
-            raise RuntimeError, +'symbols beginning with an underscore are reserved'
+            raise RuntimeError, 'symbols beginning with an underscore are reserved'
           end
         else
           if previous.nil? || previous == key
@@ -192,9 +192,9 @@ def group_by
   def slice_after(arg = undefined, &block)
     has_arg = !(undefined.equal? arg)
     if block_given?
-      raise ArgumentError, +'both pattern and block are given' if has_arg
+      raise ArgumentError, 'both pattern and block are given' if has_arg
     else
-      raise ArgumentError, +'wrong number of arguments (0 for 1)' unless has_arg
+      raise ArgumentError, 'wrong number of arguments (0 for 1)' unless has_arg
       block = Proc.new{ |elem| arg === elem }
     end
     Enumerator.new do |yielder|
@@ -219,10 +219,10 @@ def slice_before(arg = undefined, &block)
     if block_given?
       has_init = !(undefined.equal? arg)
       if has_init
-        raise ArgumentError, +'both pattern and block are given'
+        raise ArgumentError, 'both pattern and block are given'
       end
     else
-      raise ArgumentError, +'wrong number of arguments (0 for 1)' if undefined.equal? arg
+      raise ArgumentError, 'wrong number of arguments (0 for 1)' if undefined.equal? arg
       block = Proc.new{ |elem| arg === elem }
     end
     Enumerator.new do |yielder|
@@ -544,7 +544,7 @@ def cycle(many=nil)
 
   def drop(n)
     n = Truffle::Type.coerce_to_collection_index n
-    raise ArgumentError, +'attempt to drop negative size' if n < 0
+    raise ArgumentError, 'attempt to drop negative size' if n < 0
 
     ary = to_a
     return [] if n > ary.size
@@ -789,7 +789,7 @@ def min_by(n = nil, &block)
   def self.sort_proc
     @sort_proc ||= Proc.new do |a, b|
       unless ret = a <=> b
-        raise ArgumentError, +'Improper spaceship value'
+        raise ArgumentError, 'Improper spaceship value'
       end
       ret
     end
@@ -807,12 +807,12 @@ def minmax(&block)
         first_time = false
       else
         unless min_cmp = block.call(min, object)
-          raise ArgumentError, +'comparison failed'
+          raise ArgumentError, 'comparison failed'
         end
         min = object if min_cmp > 0
 
         unless max_cmp = block.call(max, object)
-          raise ArgumentError, +'comparison failed'
+          raise ArgumentError, 'comparison failed'
         end
 
         max = object if max_cmp < 0