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Diffstat (limited to 'spec/ruby/library/bigdecimal/round_spec.rb')
| -rw-r--r-- | spec/ruby/library/bigdecimal/round_spec.rb | 234 |
1 files changed, 234 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..622e129d93 --- /dev/null +++ b/spec/ruby/library/bigdecimal/round_spec.rb @@ -0,0 +1,234 @@ +require_relative '../../spec_helper' +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 + + ["BigDecimal::ROUND_UP", ":up"].each do |way| + describe way do + it "rounds values away from zero" do + mode = eval(way) + + @p1_50.round(0, mode).should == @two + @p1_51.round(0, mode).should == @two + @p1_49.round(0, mode).should == @two + @n1_50.round(0, mode).should == @neg_two + @n1_51.round(0, mode).should == @neg_two + @n1_49.round(0, mode).should == @neg_two + + @p2_50.round(0, mode).should == @three + @p2_51.round(0, mode).should == @three + @p2_49.round(0, mode).should == @three + @n2_50.round(0, mode).should == @neg_three + @n2_51.round(0, mode).should == @neg_three + @n2_49.round(0, mode).should == @neg_three + end + end + end + + ["BigDecimal::ROUND_DOWN", ":down", ":truncate"].each do |way| + describe way do + it "rounds values towards zero" do + mode = eval(way) + + @p1_50.round(0, mode).should == @one + @p1_51.round(0, mode).should == @one + @p1_49.round(0, mode).should == @one + @n1_50.round(0, mode).should == @neg_one + @n1_51.round(0, mode).should == @neg_one + @n1_49.round(0, mode).should == @neg_one + + @p2_50.round(0, mode).should == @two + @p2_51.round(0, mode).should == @two + @p2_49.round(0, mode).should == @two + @n2_50.round(0, mode).should == @neg_two + @n2_51.round(0, mode).should == @neg_two + @n2_49.round(0, mode).should == @neg_two + end + end + end + + ["BigDecimal::ROUND_HALF_UP", ":half_up", ":default"].each do |way| + describe way do + it "rounds values >= 5 up, otherwise down" do + mode = eval(way) + + @p1_50.round(0, mode).should == @two + @p1_51.round(0, mode).should == @two + @p1_49.round(0, mode).should == @one + @n1_50.round(0, mode).should == @neg_two + @n1_51.round(0, mode).should == @neg_two + @n1_49.round(0, mode).should == @neg_one + + @p2_50.round(0, mode).should == @three + @p2_51.round(0, mode).should == @three + @p2_49.round(0, mode).should == @two + @n2_50.round(0, mode).should == @neg_three + @n2_51.round(0, mode).should == @neg_three + @n2_49.round(0, mode).should == @neg_two + end + end + end + + ["BigDecimal::ROUND_HALF_DOWN", ":half_down"].each do |way| + describe way do + it "rounds values > 5 up, otherwise down" do + mode = eval(way) + + @p1_50.round(0, mode).should == @one + @p1_51.round(0, mode).should == @two + @p1_49.round(0, mode).should == @one + @n1_50.round(0, mode).should == @neg_one + @n1_51.round(0, mode).should == @neg_two + @n1_49.round(0, mode).should == @neg_one + + @p2_50.round(0, mode).should == @two + @p2_51.round(0, mode).should == @three + @p2_49.round(0, mode).should == @two + @n2_50.round(0, mode).should == @neg_two + @n2_51.round(0, mode).should == @neg_three + @n2_49.round(0, mode).should == @neg_two + end + end + end + + ["BigDecimal::ROUND_CEILING", ":ceiling", ":ceil"].each do |way| + describe way do + it "rounds values towards +infinity" do + mode = eval(way) + + @p1_50.round(0, mode).should == @two + @p1_51.round(0, mode).should == @two + @p1_49.round(0, mode).should == @two + @n1_50.round(0, mode).should == @neg_one + @n1_51.round(0, mode).should == @neg_one + @n1_49.round(0, mode).should == @neg_one + + @p2_50.round(0, mode).should == @three + @p2_51.round(0, mode).should == @three + @p2_49.round(0, mode).should == @three + @n2_50.round(0, mode).should == @neg_two + @n2_51.round(0, mode).should == @neg_two + @n2_49.round(0, mode).should == @neg_two + end + end + end + + ["BigDecimal::ROUND_FLOOR", ":floor"].each do |way| + describe way do + it "rounds values towards -infinity" do + mode = eval(way) + + @p1_50.round(0, mode).should == @one + @p1_51.round(0, mode).should == @one + @p1_49.round(0, mode).should == @one + @n1_50.round(0, mode).should == @neg_two + @n1_51.round(0, mode).should == @neg_two + @n1_49.round(0, mode).should == @neg_two + + @p2_50.round(0, mode).should == @two + @p2_51.round(0, mode).should == @two + @p2_49.round(0, mode).should == @two + @n2_50.round(0, mode).should == @neg_three + @n2_51.round(0, mode).should == @neg_three + @n2_49.round(0, mode).should == @neg_three + end + end + end + + ["BigDecimal::ROUND_HALF_EVEN", ":half_even", ":banker"].each do |way| + describe way do + it "rounds values > 5 up, < 5 down and == 5 towards even neighbor" do + mode = eval(way) + + @p1_50.round(0, mode).should == @two + @p1_51.round(0, mode).should == @two + @p1_49.round(0, mode).should == @one + @n1_50.round(0, mode).should == @neg_two + @n1_51.round(0, mode).should == @neg_two + @n1_49.round(0, mode).should == @neg_one + + @p2_50.round(0, mode).should == @two + @p2_51.round(0, mode).should == @three + @p2_49.round(0, mode).should == @two + @n2_50.round(0, mode).should == @neg_two + @n2_51.round(0, mode).should == @neg_three + @n2_49.round(0, mode).should == @neg_two + end + end + end + + it 'raise exception, if self is special value' do + -> { BigDecimal('NaN').round }.should.raise(FloatDomainError) + -> { BigDecimal('Infinity').round }.should.raise(FloatDomainError) + -> { BigDecimal('-Infinity').round }.should.raise(FloatDomainError) + end + + it 'do not raise exception, if self is special value and precision is given' do + -> { BigDecimal('NaN').round(2) }.should_not.raise(FloatDomainError) + -> { BigDecimal('Infinity').round(2) }.should_not.raise(FloatDomainError) + -> { BigDecimal('-Infinity').round(2) }.should_not.raise(FloatDomainError) + end + + it 'raise for a non-existent round mode' do + -> { @p1_50.round(0, :nonsense) }.should.raise(ArgumentError, "invalid rounding mode (nonsense)") + end +end |