diff options
Diffstat (limited to 'spec/ruby/core/bignum/divmod_spec.rb')
-rw-r--r-- | spec/ruby/core/bignum/divmod_spec.rb | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/spec/ruby/core/bignum/divmod_spec.rb b/spec/ruby/core/bignum/divmod_spec.rb new file mode 100644 index 0000000000..656f23482b --- /dev/null +++ b/spec/ruby/core/bignum/divmod_spec.rb @@ -0,0 +1,81 @@ +require File.expand_path('../../../spec_helper', __FILE__) + +describe "Bignum#divmod" do + before :each do + @bignum = bignum_value(55) + end + + # Based on MRI's test/test_integer.rb (test_divmod), + # MRI maintains the following property: + # if q, r = a.divmod(b) ==> + # assert(0 < b ? (0 <= r && r < b) : (b < r && r <= 0)) + # So, r is always between 0 and b. + it "returns an Array containing quotient and modulus obtained from dividing self by the given argument" do + @bignum.divmod(4).should == [2305843009213693965, 3] + @bignum.divmod(13).should == [709490156681136604, 11] + + @bignum.divmod(4.5).should == [2049638230412172288, 3.5] + + not_supported_on :opal do + @bignum.divmod(4.0).should == [2305843009213693952, 0.0] + @bignum.divmod(13.0).should == [709490156681136640, 8.0] + + @bignum.divmod(2.0).should == [4611686018427387904, 0.0] + end + + @bignum.divmod(bignum_value).should == [1, 55] + + (-(10**50)).divmod(-(10**40 + 1)).should == [9999999999, -9999999999999999999999999999990000000001] + (10**50).divmod(10**40 + 1).should == [9999999999, 9999999999999999999999999999990000000001] + + (-10**50).divmod(10**40 + 1).should == [-10000000000, 10000000000] + (10**50).divmod(-(10**40 + 1)).should == [-10000000000, -10000000000] + end + + describe "with q = floor(x/y), a = q*b + r," do + it "returns [q,r] when a < 0, b > 0 and |a| < b" do + a = -@bignum + 1 + b = @bignum + a.divmod(b).should == [-1, 1] + end + + it "returns [q,r] when a > 0, b < 0 and a > |b|" do + b = -@bignum + 1 + a = @bignum + a.divmod(b).should == [-2, -@bignum + 2] + end + + it "returns [q,r] when a > 0, b < 0 and a < |b|" do + a = @bignum - 1 + b = -@bignum + a.divmod(b).should == [-1, -1] + end + + it "returns [q,r] when a < 0, b < 0 and |a| < |b|" do + a = -@bignum + 1 + b = -@bignum + a.divmod(b).should == [0, -@bignum + 1] + end + end + + it "raises a ZeroDivisionError when the given argument is 0" do + lambda { @bignum.divmod(0) }.should raise_error(ZeroDivisionError) + lambda { (-@bignum).divmod(0) }.should raise_error(ZeroDivisionError) + end + + # Behaviour established as correct in r23953 + it "raises a FloatDomainError if other is NaN" do + lambda { @bignum.divmod(nan_value) }.should raise_error(FloatDomainError) + end + + it "raises a ZeroDivisionError when the given argument is 0 and a Float" do + lambda { @bignum.divmod(0.0) }.should raise_error(ZeroDivisionError) + lambda { (-@bignum).divmod(0.0) }.should raise_error(ZeroDivisionError) + end + + it "raises a TypeError when the given argument is not an Integer" do + lambda { @bignum.divmod(mock('10')) }.should raise_error(TypeError) + lambda { @bignum.divmod("10") }.should raise_error(TypeError) + lambda { @bignum.divmod(:symbol) }.should raise_error(TypeError) + end +end |