4 files changed, 101 insertions, 20 deletions

diff --git a/mrbgems/mruby-array-ext/mrbgem.rake b/mrbgems/mruby-array-ext/mrbgem.rake
index e4b5938c7..882caf1ab 100644
--- a/mrbgems/mruby-array-ext/mrbgem.rake
+++ b/mrbgems/mruby-array-ext/mrbgem.rake
@@ -1,5 +1,5 @@
 MRuby::Gem::Specification.new('mruby-array-ext') do |spec|
   spec.license = 'MIT'
   spec.author  = 'mruby developers'
-  spec.summary = 'extensional Array class'
+  spec.summary = 'Array class extension'
 end
diff --git a/mrbgems/mruby-array-ext/mrblib/array.rb b/mrbgems/mruby-array-ext/mrblib/array.rb
index fd80fa0bb..f19581cdc 100644
--- a/mrbgems/mruby-array-ext/mrblib/array.rb
+++ b/mrbgems/mruby-array-ext/mrblib/array.rb
@@ -1,6 +1,31 @@
 class Array
   ##
   # call-seq:
+  #    Array.try_convert(obj) -> array or nil
+  #
+  # Tries to convert +obj+ into an array, using +to_ary+ method.
+  # converted array or +nil+ if +obj+ cannot be converted for any reason.
+  # This method can be used to check if an argument is an array.
+  #
+  #    Array.try_convert([1])   #=> [1]
+  #    Array.try_convert("1")   #=> nil
+  #
+  #    if tmp = Array.try_convert(arg)
+  #      # the argument is an array
+  #    elsif tmp = String.try_convert(arg)
+  #      # the argument is a string
+  #    end
+  #
+  def self.try_convert(obj)
+    if obj.respond_to?(:to_ary)
+      obj.to_ary
+    else
+      nil
+    end
+  end
+
+  ##
+  # call-seq:
   #    ary.uniq!                -> ary or nil
   #    ary.uniq! { |item| ... } -> ary or nil
   #
@@ -217,7 +242,7 @@ class Array
   #    [ "a", "b", "c" ].compact!           #=> nil
   #
   def compact!
-    result = self.select { |e| e != nil }
+    result = self.select { |e| !e.nil? }
     if result.size == self.size
       nil
     else
@@ -262,7 +287,7 @@ class Array
   #
 
   def fetch(n=nil, ifnone=NONE, &block)
-    warn "block supersedes default value argument" if n != nil && ifnone != NONE && block
+    warn "block supersedes default value argument" if !n.nil? && ifnone != NONE && block
 
     idx = n
     if idx < 0
@@ -312,51 +337,51 @@ class Array
   #
 
   def fill(arg0=nil, arg1=nil, arg2=nil, &block)
-    if arg0 == nil && arg1 == nil && arg2 == nil && !block
+    if arg0.nil? && arg1.nil? && arg2.nil? && !block
       raise ArgumentError, "wrong number of arguments (0 for 1..3)"
     end
 
     beg = len = 0
     ary = []
     if block
-      if arg0 == nil && arg1 == nil && arg2 == nil
+      if arg0.nil? && arg1.nil? && arg2.nil?
         # ary.fill { |index| block }                    -> ary
         beg = 0
         len = self.size
-      elsif arg0 != nil && arg0.kind_of?(Range)
+      elsif !arg0.nil? && arg0.kind_of?(Range)
         # ary.fill(range) { |index| block }             -> ary
         beg = arg0.begin
         beg += self.size if beg < 0
         len = arg0.end
         len += self.size if len < 0
         len += 1 unless arg0.exclude_end?
-      elsif arg0 != nil
+      elsif !arg0.nil?
         # ary.fill(start [, length] ) { |index| block } -> ary
         beg = arg0
         beg += self.size if beg < 0
-        if arg1 == nil
+        if arg1.nil?
           len = self.size
         else
           len = arg0 + arg1
         end
       end
     else
-      if arg0 != nil && arg1 == nil && arg2 == nil
+      if !arg0.nil? && arg1.nil? && arg2.nil?
         # ary.fill(obj)                                 -> ary
         beg = 0
         len = self.size
-      elsif arg0 != nil && arg1 != nil && arg1.kind_of?(Range)
+      elsif !arg0.nil? && !arg1.nil? && arg1.kind_of?(Range)
         # ary.fill(obj, range )                         -> ary
         beg = arg1.begin
         beg += self.size if beg < 0
         len = arg1.end
         len += self.size if len < 0
         len += 1 unless arg1.exclude_end?
-      elsif arg0 != nil && arg1 != nil
+      elsif !arg0.nil? && !arg1.nil?
         # ary.fill(obj, start [, length])               -> ary
         beg = arg1
         beg += self.size if beg < 0
-        if arg2 == nil
+        if arg2.nil?
           len = self.size
         else
           len = beg + arg2
@@ -582,7 +607,7 @@ class Array
       elsif v == true
         satisfied = true
         smaller = true
-      elsif v == false || v == nil
+      elsif v == false || v.nil?
         smaller = false
       end
       if smaller
@@ -681,4 +706,42 @@ class Array
     return nil if self.size == result.size
     self.replace(result)
   end
+
+  ##
+  #  call-seq:
+  #     ary.index(val)            -> int or nil
+  #     ary.index {|item| block } ->  int or nil
+  #
+  #  Returns the _index_ of the first object in +ary+ such that the object is
+  #  <code>==</code> to +obj+.
+  #
+  #  If a block is given instead of an argument, returns the _index_ of the
+  #  first object for which the block returns +true+.  Returns +nil+ if no
+  #  match is found.
+  #
+  # ISO 15.2.12.5.14
+  def index(val=NONE, &block)
+    return to_enum(:find_index, val) if !block && val == NONE
+
+    if block
+      idx = 0
+      self.each do |*e|
+        return idx if block.call(*e)
+        idx += 1
+      end
+    else
+      return self.__ary_index(val)
+    end
+    nil
+  end
+
+  ##
+  #  call-seq:
+  #     ary.to_ary -> ary
+  #
+  #  Returns +self+.
+  #
+  def to_ary
+    self
+  end
 end
diff --git a/mrbgems/mruby-array-ext/src/array.c b/mrbgems/mruby-array-ext/src/array.c
index d69f0ac44..d5c96e2cc 100644
--- a/mrbgems/mruby-array-ext/src/array.c
+++ b/mrbgems/mruby-array-ext/src/array.c
@@ -1,8 +1,8 @@
-#include "mruby.h"
-#include "mruby/value.h"
-#include "mruby/array.h"
-#include "mruby/range.h"
-#include "mruby/hash.h"
+#include <mruby.h>
+#include <mruby/value.h>
+#include <mruby/array.h>
+#include <mruby/range.h>
+#include <mruby/hash.h>
 
 /*
  *  call-seq:
@@ -113,8 +113,9 @@ mrb_ary_values_at(mrb_state *mrb, mrb_value self)
  *  Returns the result of interpreting <i>aray</i> as an array of
  *  <tt>[key, value]</tt> paris.
  *
- *     [[:foo, :bar], [1, 2]].to_h
- *       # => {:foo => :bar, 1 => 2}
+ *      [[:foo, :bar], [1, 2]].to_h
+ *        # => {:foo => :bar, 1 => 2}
+ *
  */
 
 static mrb_value
diff --git a/mrbgems/mruby-array-ext/test/array.rb b/mrbgems/mruby-array-ext/test/array.rb
index 8c919f7e0..f17cb80e1 100644
--- a/mrbgems/mruby-array-ext/test/array.rb
+++ b/mrbgems/mruby-array-ext/test/array.rb
@@ -1,6 +1,13 @@
 ##
 # Array(Ext) Test
 
+assert("Array.try_convert") do
+  assert_nil Array.try_convert(0)
+  assert_nil Array.try_convert(nil)
+  assert_equal [], Array.try_convert([])
+  assert_equal [1,2,3], Array.try_convert([1,2,3])
+end
+
 assert("Array#assoc") do
   s1 = [ "colors", "red", "blue", "green" ]
   s2 = [ "letters", "a", "b", "c" ]
@@ -293,3 +300,13 @@ assert('Array#to_h') do
   assert_raise(TypeError)     { [1].to_h }
   assert_raise(ArgumentError) { [[1]].to_h }
 end
+
+assert("Array#index (block)") do
+  assert_nil (1..10).to_a.index { |i| i % 5 == 0 and i % 7 == 0 }
+  assert_equal 34, (1..100).to_a.index { |i| i % 5 == 0 and i % 7 == 0 }
+end
+
+assert("Array#to_ary") do
+  assert_equal [], [].to_ary
+  assert_equal [1,2,3], [1,2,3].to_ary
+end