1 files changed, 32 insertions, 5 deletions
diff --git a/spec/ruby/core/env/delete_if_spec.rb b/spec/ruby/core/env/delete_if_spec.rb
index d64443194e..d2de51c225 100644
--- a/spec/ruby/core/env/delete_if_spec.rb
+++ b/spec/ruby/core/env/delete_if_spec.rb
@@ -2,14 +2,31 @@ require_relative '../../spec_helper'
 require_relative '../enumerable/shared/enumeratorized'
 
 describe "ENV.delete_if" do
+  before :each do
+    @foo = ENV["foo"]
+    @bar = ENV["bar"]
+
+    ENV["foo"] = "0"
+    ENV["bar"] = "1"
+  end
+
+  after :each do
+    ENV["foo"] = @foo
+    ENV["bar"] = @bar
+  end
+
   it "deletes pairs if the block returns true" do
-    ENV["foo"] = "bar"
-    ENV.delete_if { |k, v| k == "foo" }
+    ENV.delete_if { |k, v| ["foo", "bar"].include?(k) }
     ENV["foo"].should == nil
+    ENV["bar"].should == nil
+  end
+
+  it "returns ENV when block given" do
+    ENV.delete_if { |k, v| ["foo", "bar"].include?(k) }.should equal(ENV)
   end
 
   it "returns ENV even if nothing deleted" do
-    ENV.delete_if { false }.should_not == nil
+    ENV.delete_if { false }.should equal(ENV)
   end
 
   it "returns an Enumerator if no block given" do
@@ -17,10 +34,20 @@ describe "ENV.delete_if" do
   end
 
   it "deletes pairs through enumerator" do
-    ENV["foo"] = "bar"
     enum = ENV.delete_if
-    enum.each { |k, v| k == "foo" }
+    enum.each { |k, v| ["foo", "bar"].include?(k) }
     ENV["foo"].should == nil
+    ENV["bar"].should == nil
+  end
+
+  it "returns ENV from enumerator" do
+    enum = ENV.delete_if
+    enum.each { |k, v| ["foo", "bar"].include?(k) }.should equal(ENV)
+  end
+
+  it "returns ENV from enumerator even if nothing deleted" do
+    enum = ENV.delete_if
+    enum.each { false }.should equal(ENV)
   end
 
   it_behaves_like :enumeratorized_with_origin_size, :delete_if, ENV