Added String#sub/sub! and String#gsub/gsub!

mrblib/string.rb

@@ -28,14 +28,13 @@ class String
   #
   # ISO 15.2.10.5.18
   def gsub(*args, &block)
-    unless (args.size == 1 && block) || args.size == 2
+    if args.size == 2
+      split(args[0]).join(args[1])
+    elsif args.size == 1 && block
+      split(args[0]).join(block.call(args[0]))
+    else
       raise ArgumentError, "wrong number of arguments"
     end
-
-    ### *** TODO *** ###
-    unless Object.const_defined?(:Regexp)
-      raise NotImplementedError, "gsub not available (yet)"
-    end
   end
 
   ##
@@ -76,14 +75,13 @@ class String
   #
   # ISO 15.2.10.5.36
   def sub(*args, &block)
-    unless (args.size == 1 && block) || args.size == 2
+    if args.size == 2
+      split(args[0], 2).join(args[1])
+    elsif args.size == 1 && block
+      split(args[0], 2).join(block.call(args[0]))
+    else
       raise ArgumentError, "wrong number of arguments"
     end
-
-    ### *** TODO *** ###
-    unless Object.const_defined?(:Regexp)
-      raise NotImplementedError, "sub not available (yet)"
-    end
   end
 
   ##

test/t/string.rb

@@ -192,9 +192,19 @@ assert('String#eql?', '15.2.10.5.17') do
   'abc'.eql?('abc') and not 'abc'.eql?('cba')
 end
 
-# TODO ATM broken assert('String#gsub', '15.2.10.5.18') do
+assert('String#gsub', '15.2.10.5.18') do
+  'abcabc'.gsub('b', 'B') == 'aBcaBc' && 'abcabc'.gsub('b') { |w| w.capitalize } == 'aBcaBc' 
+end
 
-# TODO ATM broken assert('String#gsub!', '15.2.10.5.19') do
+assert('String#gsub!', '15.2.10.5.19') do
+  a = 'abcabc'
+  a.gsub!('b', 'B')
+
+  b = 'abcabc'
+  b.gsub!('b') { |w| w.capitalize }
+
+  a == 'aBcaBc' && b == 'aBcaBc' 
+end
 
 assert('String#hash', '15.2.10.5.20') do
   a = 'abc'
@@ -307,9 +317,20 @@ assert('String#split', '15.2.10.5.35') do
     'abc'.split("") == ['a', 'b', 'c']
 end
 
-# TODO ATM broken assert('String#sub', '15.2.10.5.36') do
+assert('String#sub', '15.2.10.5.36') do
+  'abcabc'.sub('b', 'B') == 'aBcabc' && 'abcabc'.sub('b') { |w| w.capitalize } == 'aBcabc' 
+end
+
+assert('String#sub!', '15.2.10.5.37') do
+  a = 'abcabc'
+  a.sub!('b', 'B')
+
+  b = 'abcabc'
+  b.sub!('b') { |w| w.capitalize }
+
+  a == 'aBcabc' && b == 'aBcabc'
+end
 
-# TODO ATM broken assert('String#sub!', '15.2.10.5.37') do
 
 assert('String#to_i', '15.2.10.5.38') do
   a = ''.to_i