1 files changed, 77 insertions, 0 deletions
diff --git a/spec/ruby/core/integer/round_spec.rb b/spec/ruby/core/integer/round_spec.rb
new file mode 100644
index 0000000000..5cc9aa3881
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+++ b/spec/ruby/core/integer/round_spec.rb
@@ -0,0 +1,77 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../shared/to_i', __FILE__)
+
+describe "Integer#round" do
+  it_behaves_like(:integer_to_i, :round)
+
+  ruby_version_is ""..."2.5" do
+    it "rounds itself as a float if passed a positive precision" do
+      [2, -4, 10**70, -10**100].each do |v|
+        v.round(42).should eql(v.to_f)
+      end
+    end
+  end
+
+  ruby_version_is "2.5" do
+    it "returns itself if passed a positive precision" do
+      [2, -4, 10**70, -10**100].each do |v|
+        v.round(42).should eql(v)
+      end
+    end
+  end
+
+  it "returns itself if passed zero" do
+    [2, -4, 10**70, -10**100].each do |v|
+      v.round(0).should eql(v)
+    end
+  end
+
+  # redmine:5228
+  it "returns itself rounded if passed a negative value" do
+    +249.round(-2).should eql(+200)
+    -249.round(-2).should eql(-200)
+    (+25 * 10**70 - 1).round(-71).should eql(+20 * 10**70)
+    (-25 * 10**70 + 1).round(-71).should eql(-20 * 10**70)
+  end
+
+  it "returns itself rounded to nearest if passed a negative value" do
+    +250.round(-2).should eql(+300)
+    -250.round(-2).should eql(-300)
+    (+25 * 10**70).round(-71).should eql(+30 * 10**70)
+    (-25 * 10**70).round(-71).should eql(-30 * 10**70)
+  end
+
+  platform_is_not wordsize: 32 do
+    it "raises a RangeError when passed a big negative value" do
+      lambda { 42.round(fixnum_min) }.should raise_error(RangeError)
+    end
+  end
+
+  it "raises a RangeError when passed Float::INFINITY" do
+    lambda { 42.round(Float::INFINITY) }.should raise_error(RangeError)
+  end
+
+  it "raises a RangeError when passed a beyond signed int" do
+    lambda { 42.round(1<<31) }.should raise_error(RangeError)
+  end
+
+  it "raises a TypeError when passed a String" do
+    lambda { 42.round("4") }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError when its argument cannot be converted to an Integer" do
+    lambda { 42.round(nil) }.should raise_error(TypeError)
+  end
+
+  it "calls #to_int on the argument to convert it to an Integer" do
+    obj = mock("Object")
+    obj.should_receive(:to_int).and_return(0)
+    42.round(obj)
+  end
+
+  it "raises a TypeError when #to_int does not return an Integer" do
+    obj = mock("Object")
+    obj.stub!(:to_int).and_return([])
+    lambda { 42.round(obj) }.should raise_error(TypeError)
+  end
+end