Add in-tree mspec and ruby/spec

* For easier modifications of ruby/spec by MRI developers.
* .gitignore: track changes under spec.
* spec/mspec, spec/rubyspec: add in-tree mspec and ruby/spec.
  These files can therefore be updated like any other file in MRI.
  Instructions are provided in spec/README.
  [Feature #13156] [ruby-core:79246]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58595 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 49 insertions, 0 deletions

diff --git a/spec/rubyspec/core/range/first_spec.rb b/spec/rubyspec/core/range/first_spec.rb
new file mode 100644
index 0000000000..7cd3781d34
--- /dev/null
+++ b/spec/rubyspec/core/range/first_spec.rb
@@ -0,0 +1,49 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/begin', __FILE__)
+
+describe "Range#first" do
+  it_behaves_like(:range_begin, :first)
+
+  it "returns the specified number of elements from the beginning" do
+    (0..2).first(2).should == [0, 1]
+  end
+
+  it "returns an empty array for an empty Range" do
+    (0...0).first(2).should == []
+  end
+
+  it "returns an empty array when passed zero" do
+    (0..2).first(0).should == []
+  end
+
+  it "returns all elements in the range when count exceeds the number of elements" do
+    (0..2).first(4).should == [0, 1, 2]
+  end
+
+  it "raises an ArgumentError when count is negative" do
+    lambda { (0..2).first(-1) }.should raise_error(ArgumentError)
+  end
+
+  it "calls #to_int to convert the argument" do
+    obj = mock_int(2)
+    (3..7).first(obj).should == [3, 4]
+  end
+
+  it "raises a TypeError if #to_int does not return an Integer" do
+    obj = mock("to_int")
+    obj.should_receive(:to_int).and_return("1")
+    lambda { (2..3).first(obj) }.should raise_error(TypeError)
+  end
+
+  it "truncates the value when passed a Float" do
+    (2..9).first(2.8).should == [2, 3]
+  end
+
+  it "raises a TypeError when passed nil" do
+    lambda { (2..3).first(nil) }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError when passed a String" do
+    lambda { (2..3).first("1") }.should raise_error(TypeError)
+  end
+end