array.c: bsearch_index

* array.c (rb_ary_bsearch_index): Implement Array#bsearch_index
  method, which is similar to bsearch and returns the index or
  nil.  [Feature #10730]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50839 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 35 insertions, 0 deletions

diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index dd0357d132..f6d0d3d434 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -2529,6 +2529,41 @@ class TestArray < Test::Unit::TestCase
     assert_include([4, 7], a.bsearch {|x| (2**100).coerce((1 - x / 4) * (2**100)).first })
   end
 
+  def test_bsearch_index_typechecks_return_values
+    assert_raise(TypeError) do
+      [1, 2, 42, 100, 666].bsearch_index {"not ok"}
+    end
+    assert_equal [1, 2, 42, 100, 666].bsearch_index {}, [1, 2, 42, 100, 666].bsearch_index {false}
+  end
+
+  def test_bsearch_index_with_no_block
+    enum = [1, 2, 42, 100, 666].bsearch_index
+    assert_nil enum.size
+    assert_equal 2, enum.each{|x| x >= 33 }
+  end
+
+  def test_bsearch_index_in_find_minimum_mode
+    a = [0, 4, 7, 10, 12]
+    assert_equal(1, a.bsearch_index {|x| x >=   4 })
+    assert_equal(2, a.bsearch_index {|x| x >=   6 })
+    assert_equal(0, a.bsearch_index {|x| x >=  -1 })
+    assert_equal(nil, a.bsearch_index {|x| x >= 100 })
+  end
+
+  def test_bsearch_index_in_find_any_mode
+    a = [0, 4, 7, 10, 12]
+    assert_include([1, 2], a.bsearch_index {|x| 1 - x / 4 })
+    assert_equal(nil, a.bsearch_index {|x| 4 - x / 2 })
+    assert_equal(nil, a.bsearch_index {|x| 1 })
+    assert_equal(nil, a.bsearch_index {|x| -1 })
+
+    assert_include([1, 2], a.bsearch_index {|x| (1 - x / 4) * (2**100) })
+    assert_equal(nil, a.bsearch_index {|x|   1  * (2**100) })
+    assert_equal(nil, a.bsearch_index {|x| (-1) * (2**100) })
+
+    assert_include([1, 2], a.bsearch_index {|x| (2**100).coerce((1 - x / 4) * (2**100)).first })
+  end
+
   def test_shared_marking
     reduce = proc do |s|
       s.gsub(/(verify_internal_consistency_reachable_i:\sWB\smiss\s\S+\s\(T_ARRAY\)\s->\s)\S+\s\((proc|T_NONE)\)\n