Add a new #filter alias for #select

* In Enumerable, Enumerator::Lazy, Array, Hash and Set
  [Feature #13784] [ruby-core:82285]
* Share specs for the various #select#select! methods and
  reuse them for #filter/#filter!.
* Add corresponding filter tests for select tests.
* Update NEWS.

[Fix GH-1824]

From: Alexander Patrick <adp90@case.edu>

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62575 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 27 insertions, 0 deletions

diff --git a/test/ruby/test_env.rb b/test/ruby/test_env.rb
index ffed94efa6..699f7db084 100644
--- a/test/ruby/test_env.rb
+++ b/test/ruby/test_env.rb
@@ -222,6 +222,18 @@ class TestEnv < Test::Unit::TestCase
     assert_nil(ENV.select! {|k, v| IGNORE_CASE ? k.upcase != "TEST" : k != "test" })
   end
 
+  def test_filter_bang
+    h1 = {}
+    ENV.each_pair {|k, v| h1[k] = v }
+    ENV["test"] = "foo"
+    ENV.filter! {|k, v| IGNORE_CASE ? k.upcase != "TEST" : k != "test" }
+    h2 = {}
+    ENV.each_pair {|k, v| h2[k] = v }
+    assert_equal(h1, h2)
+
+    assert_nil(ENV.filter! {|k, v| IGNORE_CASE ? k.upcase != "TEST" : k != "test" })
+  end
+
   def test_keep_if
     h1 = {}
     ENV.each_pair {|k, v| h1[k] = v }
@@ -254,6 +266,21 @@ class TestEnv < Test::Unit::TestCase
     end
   end
 
+  def test_filter
+    ENV["test"] = "foo"
+    h = ENV.filter {|k| IGNORE_CASE ? k.upcase == "TEST" : k == "test" }
+    assert_equal(1, h.size)
+    k = h.keys.first
+    v = h.values.first
+    if IGNORE_CASE
+      assert_equal("TEST", k.upcase)
+      assert_equal("FOO", v.upcase)
+    else
+      assert_equal("test", k)
+      assert_equal("foo", v)
+    end
+  end
+
   def test_clear
     ENV.clear
     assert_equal(0, ENV.size)