1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
|
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?(Integer).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?(Integer).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?(Integer).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
|
