require_relative 'spec_helper' load_extension("bignum") def ensure_bignum(n) raise "Bignum#coerce returned Fixnum" if fixnum_min <= n && n <= fixnum_max n end full_range_longs = (fixnum_max == 2**(0.size * 8 - 1) - 1) describe "CApiBignumSpecs" do before :each do @s = CApiBignumSpecs.new if full_range_longs @max_long = 2**(0.size * 8 - 1) - 1 @min_long = -@max_long - 1 @max_ulong = ensure_bignum(2**(0.size * 8) - 1) else @max_long = ensure_bignum(2**(0.size * 8 - 1) - 1) @min_long = ensure_bignum(-@max_long - 1) @max_ulong = ensure_bignum(2**(0.size * 8) - 1) end end describe "rb_big2long" do unless full_range_longs it "converts a Bignum" do @s.rb_big2long(@max_long).should == @max_long @s.rb_big2long(@min_long).should == @min_long end end it "raises RangeError if passed Bignum overflow long" do -> { @s.rb_big2long(ensure_bignum(@max_long + 1)) }.should raise_error(RangeError) -> { @s.rb_big2long(ensure_bignum(@min_long - 1)) }.should raise_error(RangeError) end end describe "rb_big2ll" do unless full_range_longs it "converts a Bignum" do @s.rb_big2ll(@max_long).should == @max_long @s.rb_big2ll(@min_long).should == @min_long end end it "raises RangeError if passed Bignum overflow long" do -> { @s.rb_big2ll(ensure_bignum(@max_long << 40)) }.should raise_error(RangeError) -> { @s.rb_big2ll(ensure_bignum(@min_long << 40)) }.should raise_error(RangeError) end end describe "rb_big2ulong" do it "converts a Bignum" do @s.rb_big2ulong(@max_ulong).should == @max_ulong end unless full_range_longs it "wraps around if passed a negative bignum" do @s.rb_big2ulong(ensure_bignum(@min_long + 1)).should == -(@min_long - 1) @s.rb_big2ulong(ensure_bignum(@min_long)).should == -(@min_long) end end it "raises RangeError if passed Bignum overflow long" do -> { @s.rb_big2ulong(ensure_bignum(@max_ulong + 1)) }.should raise_error(RangeError) -> { @s.rb_big2ulong(ensure_bignum(@min_long - 1)) }.should raise_error(RangeError) end end describe "rb_big2dbl" do it "converts a Bignum to a double value" do @s.rb_big2dbl(ensure_bignum(Float::MAX.to_i)).eql?(Float::MAX).should == true end it "returns Infinity if the number is too big for a double" do huge_bignum = ensure_bignum(Float::MAX.to_i * 2) @s.rb_big2dbl(huge_bignum).should == infinity_value end it "returns -Infinity if the number is negative and too big for a double" do huge_bignum = -ensure_bignum(Float::MAX.to_i * 2) @s.rb_big2dbl(huge_bignum).should == -infinity_value end end describe "rb_big2str" do it "converts a Bignum to a string with base 10" do @s.rb_big2str(ensure_bignum(2**70), 10).eql?("1180591620717411303424").should == true end it "converts a Bignum to a string with a different base" do @s.rb_big2str(ensure_bignum(2**70), 16).eql?("400000000000000000").should == true end end describe "RBIGNUM_SIGN" do it "returns 1 for a positive Bignum" do @s.RBIGNUM_SIGN(bignum_value(1)).should == 1 end it "returns 0 for a negative Bignum" do @s.RBIGNUM_SIGN(-bignum_value(1)).should == 0 end end describe "rb_big_cmp" do it "compares a Bignum with a Bignum" do @s.rb_big_cmp(bignum_value, bignum_value(1)).should == -1 end it "compares a Bignum with a Fixnum" do @s.rb_big_cmp(bignum_value, 5).should == 1 end end describe "rb_big_pack" do it "packs a Bignum into an unsigned long" do val = @s.rb_big_pack(@max_ulong) val.should == @max_ulong end platform_is wordsize: 64 do it "packs max_ulong into 2 ulongs to allow sign bit" do val = @s.rb_big_pack_length(@max_ulong) val.should == 2 val = @s.rb_big_pack_array(@max_ulong, 2) val[0].should == @max_ulong val[1].should == 0 end it "packs a 72-bit positive Bignum into 2 unsigned longs" do num = 2 ** 71 val = @s.rb_big_pack_length(num) val.should == 2 end it "packs a 72-bit positive Bignum into correct 2 longs" do num = 2 ** 71 + 1 val = @s.rb_big_pack_array(num, 2) val[0].should == 1; val[1].should == 0x80; end it "packs a 72-bit negative Bignum into correct 2 longs" do num = -(2 ** 71 + 1) val = @s.rb_big_pack_array(num, @s.rb_big_pack_length(num)) val[0].should == @max_ulong; val[1].should == @max_ulong - 0x80; end it "packs lower order bytes into least significant bytes of longs for positive bignum" do num = 0 32.times { |i| num += i << (i * 8) } val = @s.rb_big_pack_array(num, @s.rb_big_pack_length(num)) val.size.should == 4 32.times do |i| a_long = val[i/8] a_byte = (a_long >> ((i % 8) * 8)) & 0xff a_byte.should == i end end it "packs lower order bytes into least significant bytes of longs for negative bignum" do num = 0 32.times { |i| num += i << (i * 8) } num = -num val = @s.rb_big_pack_array(num, @s.rb_big_pack_length(num)) val.size.should == 4 expected_bytes = [0x00, 0xff, 0xfd, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8, 0xf7, 0xf6, 0xf5, 0xf4, 0xf3, 0xf2, 0xf1, 0xf0, 0xef, 0xee, 0xed, 0xec, 0xeb, 0xea, 0xe9, 0xe8, 0xe7, 0xe6, 0xe5, 0xe4, 0xe3, 0xe2, 0xe1, 0xe0 ] 32.times do |i| a_long = val[i/8] a_byte = (a_long >> ((i % 8) * 8)) & 0xff a_byte.should == expected_bytes[i] end end end end describe "rb_dbl2big" do it "returns a Fixnum for a Fixnum input value" do val = @s.rb_dbl2big(2) val.kind_of?(Fixnum).should == true val.should == 2 end it "returns a Fixnum for a Float input value" do val = @s.rb_dbl2big(2.5) val.kind_of?(Fixnum).should == true val.should == 2 end it "returns a Bignum for a large enough Float input value" do input = 219238102380912830988.5 # chosen by fair dice roll val = @s.rb_dbl2big(input) val.kind_of?(Bignum).should == true # This value is based on the output of a simple C extension that uses # rb_dbl2big() to convert the above input value to a Bignum. val.should == 219238102380912836608 end it "raises FloatDomainError for Infinity values" do inf = 1.0 / 0 -> { @s.rb_dbl2big(inf) }.should raise_error(FloatDomainError) end it "raises FloatDomainError for NaN values" do nan = 0.0 / 0 -> { @s.rb_dbl2big(nan) }.should raise_error(FloatDomainError) end end end