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Diffstat (limited to 'spec/ruby/library/bigdecimal/round_spec.rb')
| -rw-r--r-- | spec/ruby/library/bigdecimal/round_spec.rb | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/spec/ruby/library/bigdecimal/round_spec.rb b/spec/ruby/library/bigdecimal/round_spec.rb new file mode 100644 index 0000000000..6c1987c5d8 --- /dev/null +++ b/spec/ruby/library/bigdecimal/round_spec.rb @@ -0,0 +1,202 @@ +require File.expand_path('../../../spec_helper', __FILE__) +require 'bigdecimal' + +describe "BigDecimal#round" do + before :each do + @one = BigDecimal("1") + @two = BigDecimal("2") + @three = BigDecimal("3") + + @neg_one = BigDecimal("-1") + @neg_two = BigDecimal("-2") + @neg_three = BigDecimal("-3") + + @p1_50 = BigDecimal("1.50") + @p1_51 = BigDecimal("1.51") + @p1_49 = BigDecimal("1.49") + @n1_50 = BigDecimal("-1.50") + @n1_51 = BigDecimal("-1.51") + @n1_49 = BigDecimal("-1.49") + + @p2_50 = BigDecimal("2.50") + @p2_51 = BigDecimal("2.51") + @p2_49 = BigDecimal("2.49") + @n2_50 = BigDecimal("-2.50") + @n2_51 = BigDecimal("-2.51") + @n2_49 = BigDecimal("-2.49") + end + + after :each do + BigDecimal.mode(BigDecimal::ROUND_MODE, BigDecimal::ROUND_HALF_UP) + end + + it "uses default rounding method unless given" do + @p1_50.round(0).should == @two + @p1_51.round(0).should == @two + @p1_49.round(0).should == @one + @n1_50.round(0).should == @neg_two + @n1_51.round(0).should == @neg_two + @n1_49.round(0).should == @neg_one + + @p2_50.round(0).should == @three + @p2_51.round(0).should == @three + @p2_49.round(0).should == @two + @n2_50.round(0).should == @neg_three + @n2_51.round(0).should == @neg_three + @n2_49.round(0).should == @neg_two + + BigDecimal.mode(BigDecimal::ROUND_MODE, BigDecimal::ROUND_DOWN) + + @p1_50.round(0).should == @one + @p1_51.round(0).should == @one + @p1_49.round(0).should == @one + @n1_50.round(0).should == @neg_one + @n1_51.round(0).should == @neg_one + @n1_49.round(0).should == @neg_one + + @p2_50.round(0).should == @two + @p2_51.round(0).should == @two + @p2_49.round(0).should == @two + @n2_50.round(0).should == @neg_two + @n2_51.round(0).should == @neg_two + @n2_49.round(0).should == @neg_two + end + + describe "BigDecimal::ROUND_UP" do + it "rounds values away from zero" do + @p1_50.round(0, BigDecimal::ROUND_UP).should == @two + @p1_51.round(0, BigDecimal::ROUND_UP).should == @two + @p1_49.round(0, BigDecimal::ROUND_UP).should == @two + @n1_50.round(0, BigDecimal::ROUND_UP).should == @neg_two + @n1_51.round(0, BigDecimal::ROUND_UP).should == @neg_two + @n1_49.round(0, BigDecimal::ROUND_UP).should == @neg_two + + @p2_50.round(0, BigDecimal::ROUND_UP).should == @three + @p2_51.round(0, BigDecimal::ROUND_UP).should == @three + @p2_49.round(0, BigDecimal::ROUND_UP).should == @three + @n2_50.round(0, BigDecimal::ROUND_UP).should == @neg_three + @n2_51.round(0, BigDecimal::ROUND_UP).should == @neg_three + @n2_49.round(0, BigDecimal::ROUND_UP).should == @neg_three + end + end + + describe "BigDecimal::ROUND_DOWN" do + it "rounds values towards zero" do + @p1_50.round(0, BigDecimal::ROUND_DOWN).should == @one + @p1_51.round(0, BigDecimal::ROUND_DOWN).should == @one + @p1_49.round(0, BigDecimal::ROUND_DOWN).should == @one + @n1_50.round(0, BigDecimal::ROUND_DOWN).should == @neg_one + @n1_51.round(0, BigDecimal::ROUND_DOWN).should == @neg_one + @n1_49.round(0, BigDecimal::ROUND_DOWN).should == @neg_one + + @p2_50.round(0, BigDecimal::ROUND_DOWN).should == @two + @p2_51.round(0, BigDecimal::ROUND_DOWN).should == @two + @p2_49.round(0, BigDecimal::ROUND_DOWN).should == @two + @n2_50.round(0, BigDecimal::ROUND_DOWN).should == @neg_two + @n2_51.round(0, BigDecimal::ROUND_DOWN).should == @neg_two + @n2_49.round(0, BigDecimal::ROUND_DOWN).should == @neg_two + end + end + + describe "BigDecimal::ROUND_HALF_UP" do + it "rounds values >= 5 up, otherwise down" do + @p1_50.round(0, BigDecimal::ROUND_HALF_UP).should == @two + @p1_51.round(0, BigDecimal::ROUND_HALF_UP).should == @two + @p1_49.round(0, BigDecimal::ROUND_HALF_UP).should == @one + @n1_50.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_two + @n1_51.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_two + @n1_49.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_one + + @p2_50.round(0, BigDecimal::ROUND_HALF_UP).should == @three + @p2_51.round(0, BigDecimal::ROUND_HALF_UP).should == @three + @p2_49.round(0, BigDecimal::ROUND_HALF_UP).should == @two + @n2_50.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_three + @n2_51.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_three + @n2_49.round(0, BigDecimal::ROUND_HALF_UP).should == @neg_two + end + end + + describe "BigDecimal::ROUND_HALF_DOWN" do + it "rounds values > 5 up, otherwise down" do + @p1_50.round(0, BigDecimal::ROUND_HALF_DOWN).should == @one + @p1_51.round(0, BigDecimal::ROUND_HALF_DOWN).should == @two + @p1_49.round(0, BigDecimal::ROUND_HALF_DOWN).should == @one + @n1_50.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_one + @n1_51.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_two + @n1_49.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_one + + @p2_50.round(0, BigDecimal::ROUND_HALF_DOWN).should == @two + @p2_51.round(0, BigDecimal::ROUND_HALF_DOWN).should == @three + @p2_49.round(0, BigDecimal::ROUND_HALF_DOWN).should == @two + @n2_50.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_two + @n2_51.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_three + @n2_49.round(0, BigDecimal::ROUND_HALF_DOWN).should == @neg_two + end + end + + describe "BigDecimal::ROUND_CEILING" do + it "rounds values towards +infinity" do + @p1_50.round(0, BigDecimal::ROUND_CEILING).should == @two + @p1_51.round(0, BigDecimal::ROUND_CEILING).should == @two + @p1_49.round(0, BigDecimal::ROUND_CEILING).should == @two + @n1_50.round(0, BigDecimal::ROUND_CEILING).should == @neg_one + @n1_51.round(0, BigDecimal::ROUND_CEILING).should == @neg_one + @n1_49.round(0, BigDecimal::ROUND_CEILING).should == @neg_one + + @p2_50.round(0, BigDecimal::ROUND_CEILING).should == @three + @p2_51.round(0, BigDecimal::ROUND_CEILING).should == @three + @p2_49.round(0, BigDecimal::ROUND_CEILING).should == @three + @n2_50.round(0, BigDecimal::ROUND_CEILING).should == @neg_two + @n2_51.round(0, BigDecimal::ROUND_CEILING).should == @neg_two + @n2_49.round(0, BigDecimal::ROUND_CEILING).should == @neg_two + end + end + + describe "BigDecimal::ROUND_FLOOR" do + it "rounds values towards -infinity" do + @p1_50.round(0, BigDecimal::ROUND_FLOOR).should == @one + @p1_51.round(0, BigDecimal::ROUND_FLOOR).should == @one + @p1_49.round(0, BigDecimal::ROUND_FLOOR).should == @one + @n1_50.round(0, BigDecimal::ROUND_FLOOR).should == @neg_two + @n1_51.round(0, BigDecimal::ROUND_FLOOR).should == @neg_two + @n1_49.round(0, BigDecimal::ROUND_FLOOR).should == @neg_two + + @p2_50.round(0, BigDecimal::ROUND_FLOOR).should == @two + @p2_51.round(0, BigDecimal::ROUND_FLOOR).should == @two + @p2_49.round(0, BigDecimal::ROUND_FLOOR).should == @two + @n2_50.round(0, BigDecimal::ROUND_FLOOR).should == @neg_three + @n2_51.round(0, BigDecimal::ROUND_FLOOR).should == @neg_three + @n2_49.round(0, BigDecimal::ROUND_FLOOR).should == @neg_three + end + end + + describe "BigDecimal::ROUND_HALF_EVEN" do + it "rounds values > 5 up, < 5 down and == 5 towards even neighbor" do + @p1_50.round(0, BigDecimal::ROUND_HALF_EVEN).should == @two + @p1_51.round(0, BigDecimal::ROUND_HALF_EVEN).should == @two + @p1_49.round(0, BigDecimal::ROUND_HALF_EVEN).should == @one + @n1_50.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_two + @n1_51.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_two + @n1_49.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_one + + @p2_50.round(0, BigDecimal::ROUND_HALF_EVEN).should == @two + @p2_51.round(0, BigDecimal::ROUND_HALF_EVEN).should == @three + @p2_49.round(0, BigDecimal::ROUND_HALF_EVEN).should == @two + @n2_50.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_two + @n2_51.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_three + @n2_49.round(0, BigDecimal::ROUND_HALF_EVEN).should == @neg_two + end + end + + it 'raise exception, if self is special value' do + lambda { BigDecimal('NaN').round }.should raise_error(FloatDomainError) + lambda { BigDecimal('Infinity').round }.should raise_error(FloatDomainError) + lambda { BigDecimal('-Infinity').round }.should raise_error(FloatDomainError) + end + + it 'do not raise exception, if self is special value and precision is given' do + lambda { BigDecimal('NaN').round(2) }.should_not raise_error(FloatDomainError) + lambda { BigDecimal('Infinity').round(2) }.should_not raise_error(FloatDomainError) + lambda { BigDecimal('-Infinity').round(2) }.should_not raise_error(FloatDomainError) + end +end |