1 files changed, 89 insertions, 0 deletions
diff --git a/spec/ruby/core/hash/to_proc_spec.rb b/spec/ruby/core/hash/to_proc_spec.rb
new file mode 100644
index 0000000000..b486d188b7
--- /dev/null
+++ b/spec/ruby/core/hash/to_proc_spec.rb
@@ -0,0 +1,89 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+ruby_version_is "2.3" do
+  describe "Hash#to_proc" do
+    before :each do
+      @key = Object.new
+      @value = Object.new
+      @hash = { @key => @value }
+      @default = Object.new
+      @unstored = Object.new
+    end
+
+    it "returns an instance of Proc" do
+      @hash.to_proc.should be_an_instance_of Proc
+    end
+
+    describe "the returned proc" do
+      before :each do
+        @proc = @hash.to_proc
+      end
+
+      it "is not a lambda" do
+        @proc.lambda?.should == false
+      end
+
+      it "raises ArgumentError if not passed exactly one argument" do
+        lambda {
+          @proc.call
+        }.should raise_error(ArgumentError)
+
+        lambda {
+          @proc.call 1, 2
+        }.should raise_error(ArgumentError)
+      end
+
+      context "with a stored key" do
+        it "returns the paired value" do
+          @proc.call(@key).should equal(@value)
+        end
+      end
+
+      context "passed as a block" do
+        it "retrieves the hash's values" do
+          [@key].map(&@proc)[0].should equal(@value)
+        end
+
+        context "to instance_exec" do
+          it "always retrieves the original hash's values" do
+            hash = {foo: 1, bar: 2}
+            proc = hash.to_proc
+
+            hash.instance_exec(:foo, &proc).should == 1
+
+            hash2 = {quux: 1}
+            hash2.instance_exec(:foo, &proc).should == 1
+          end
+        end
+      end
+
+      context "with no stored key" do
+        it "returns nil" do
+          @proc.call(@unstored).should be_nil
+        end
+
+        context "when the hash has a default value" do
+          before :each do
+            @hash.default = @default
+          end
+
+          it "returns the default value" do
+            @proc.call(@unstored).should equal(@default)
+          end
+        end
+
+        context "when the hash has a default proc" do
+          it "returns an evaluated value from the default proc" do
+            @hash.default_proc = -> hash, called_with { [hash.keys, called_with] }
+            @proc.call(@unstored).should == [[@key], @unstored]
+          end
+        end
+      end
+
+      it "raises an ArgumentError when calling #call on the Proc with no arguments" do
+        lambda { @hash.to_proc.call }.should raise_error(ArgumentError)
+      end
+    end
+  end
+end