1 files changed, 37 insertions, 0 deletions
diff --git a/spec/ruby/core/set/keep_if_spec.rb b/spec/ruby/core/set/keep_if_spec.rb
new file mode 100644
index 0000000000..7ca5d0cd43
--- /dev/null
+++ b/spec/ruby/core/set/keep_if_spec.rb
@@ -0,0 +1,37 @@
+require_relative '../../spec_helper'
+
+describe "Set#keep_if" do
+  before :each do
+    @set = Set["one", "two", "three"]
+  end
+
+  it "yields every element of self" do
+    ret = []
+    @set.keep_if { |x| ret << x }
+    ret.sort.should == ["one", "two", "three"].sort
+  end
+
+  it "keeps every element from self for which the passed block returns true" do
+    @set.keep_if { |x| x.size != 3 }
+    @set.size.should.eql?(1)
+
+    @set.should_not.include?("one")
+    @set.should_not.include?("two")
+    @set.should.include?("three")
+  end
+
+  it "returns self" do
+    @set.keep_if {}.should.equal?(@set)
+  end
+
+  it "returns an Enumerator when passed no block" do
+    enum = @set.keep_if
+    enum.should.instance_of?(Enumerator)
+
+    enum.each { |x| x.size != 3 }
+
+    @set.should_not.include?("one")
+    @set.should_not.include?("two")
+    @set.should.include?("three")
+  end
+end