1 // Translated from C to Rust. The original C code can be found at
2 // https://github.com/ulfjack/ryu and carries the following license:
3 //
4 // Copyright 2018 Ulf Adams
5 //
6 // The contents of this file may be used under the terms of the Apache License,
7 // Version 2.0.
8 //
9 // (See accompanying file LICENSE-Apache or copy at
10 // http://www.apache.org/licenses/LICENSE-2.0)
11 //
12 // Alternatively, the contents of this file may be used under the terms of
13 // the Boost Software License, Version 1.0.
14 // (See accompanying file LICENSE-Boost or copy at
15 // https://www.boost.org/LICENSE_1_0.txt)
16 //
17 // Unless required by applicable law or agreed to in writing, this software
18 // is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
19 // KIND, either express or implied.
20
21 #[macro_use]
22 mod macros;
23
24 use std::f64;
25
pretty(f: f64) -> String26 fn pretty(f: f64) -> String {
27 ryu::Buffer::new().format(f).to_owned()
28 }
29
ieee_parts_to_double(sign: bool, ieee_exponent: u32, ieee_mantissa: u64) -> f6430 fn ieee_parts_to_double(sign: bool, ieee_exponent: u32, ieee_mantissa: u64) -> f64 {
31 assert!(ieee_exponent <= 2047);
32 assert!(ieee_mantissa <= (1u64 << 53) - 1);
33 f64::from_bits(((sign as u64) << 63) | ((ieee_exponent as u64) << 52) | ieee_mantissa)
34 }
35
36 #[test]
test_ryu()37 fn test_ryu() {
38 check!(0.3);
39 check!(1234000000000000.0);
40 check!(1.234e16);
41 check!(2.71828);
42 check!(1.1e128);
43 check!(1.1e-64);
44 check!(2.718281828459045);
45 check!(5e-324);
46 check!(1.7976931348623157e308);
47 }
48
49 #[test]
test_random()50 fn test_random() {
51 let n = if cfg!(miri) { 100 } else { 1000000 };
52 let mut buffer = ryu::Buffer::new();
53 for _ in 0..n {
54 let f: f64 = rand::random();
55 assert_eq!(f, buffer.format_finite(f).parse().unwrap());
56 }
57 }
58
59 #[test]
60 #[cfg_attr(miri, ignore)]
test_non_finite()61 fn test_non_finite() {
62 for i in 0u64..1 << 23 {
63 let f = f64::from_bits((((1 << 11) - 1) << 52) + (i << 29));
64 assert!(!f.is_finite(), "f={}", f);
65 ryu::Buffer::new().format_finite(f);
66 }
67 }
68
69 #[test]
test_basic()70 fn test_basic() {
71 check!(0.0);
72 check!(-0.0);
73 check!(1.0);
74 check!(-1.0);
75 assert_eq!(pretty(f64::NAN), "NaN");
76 assert_eq!(pretty(f64::INFINITY), "inf");
77 assert_eq!(pretty(f64::NEG_INFINITY), "-inf");
78 }
79
80 #[test]
test_switch_to_subnormal()81 fn test_switch_to_subnormal() {
82 check!(2.2250738585072014e-308);
83 }
84
85 #[test]
test_min_and_max()86 fn test_min_and_max() {
87 assert_eq!(f64::from_bits(0x7fefffffffffffff), 1.7976931348623157e308);
88 check!(1.7976931348623157e308);
89 assert_eq!(f64::from_bits(1), 5e-324);
90 check!(5e-324);
91 }
92
93 #[test]
test_lots_of_trailing_zeros()94 fn test_lots_of_trailing_zeros() {
95 check!(2.9802322387695312e-8);
96 }
97
98 #[test]
test_regression()99 fn test_regression() {
100 check!(-2.109808898695963e16);
101 check!(4.940656e-318);
102 check!(1.18575755e-316);
103 check!(2.989102097996e-312);
104 check!(9060801153433600.0);
105 check!(4.708356024711512e18);
106 check!(9.409340012568248e18);
107 check!(1.2345678);
108 }
109
110 #[test]
test_looks_like_pow5()111 fn test_looks_like_pow5() {
112 // These numbers have a mantissa that is a multiple of the largest power of
113 // 5 that fits, and an exponent that causes the computation for q to result
114 // in 22, which is a corner case for Ryū.
115 assert_eq!(f64::from_bits(0x4830F0CF064DD592), 5.764607523034235e39);
116 check!(5.764607523034235e39);
117 assert_eq!(f64::from_bits(0x4840F0CF064DD592), 1.152921504606847e40);
118 check!(1.152921504606847e40);
119 assert_eq!(f64::from_bits(0x4850F0CF064DD592), 2.305843009213694e40);
120 check!(2.305843009213694e40);
121 }
122
123 #[test]
test_output_length()124 fn test_output_length() {
125 check!(1.0); // already tested in Basic
126 check!(1.2);
127 check!(1.23);
128 check!(1.234);
129 check!(1.2345);
130 check!(1.23456);
131 check!(1.234567);
132 check!(1.2345678); // already tested in Regression
133 check!(1.23456789);
134 check!(1.234567895); // 1.234567890 would be trimmed
135 check!(1.2345678901);
136 check!(1.23456789012);
137 check!(1.234567890123);
138 check!(1.2345678901234);
139 check!(1.23456789012345);
140 check!(1.234567890123456);
141 check!(1.2345678901234567);
142
143 // Test 32-bit chunking
144 check!(4.294967294); // 2^32 - 2
145 check!(4.294967295); // 2^32 - 1
146 check!(4.294967296); // 2^32
147 check!(4.294967297); // 2^32 + 1
148 check!(4.294967298); // 2^32 + 2
149 }
150
151 // Test min, max shift values in shiftright128
152 #[test]
test_min_max_shift()153 fn test_min_max_shift() {
154 let max_mantissa = (1u64 << 53) - 1;
155
156 // 32-bit opt-size=0: 49 <= dist <= 50
157 // 32-bit opt-size=1: 30 <= dist <= 50
158 // 64-bit opt-size=0: 50 <= dist <= 50
159 // 64-bit opt-size=1: 30 <= dist <= 50
160 assert_eq!(1.7800590868057611E-307, ieee_parts_to_double(false, 4, 0));
161 check!(1.7800590868057611e-307);
162 // 32-bit opt-size=0: 49 <= dist <= 49
163 // 32-bit opt-size=1: 28 <= dist <= 49
164 // 64-bit opt-size=0: 50 <= dist <= 50
165 // 64-bit opt-size=1: 28 <= dist <= 50
166 assert_eq!(
167 2.8480945388892175E-306,
168 ieee_parts_to_double(false, 6, max_mantissa)
169 );
170 check!(2.8480945388892175e-306);
171 // 32-bit opt-size=0: 52 <= dist <= 53
172 // 32-bit opt-size=1: 2 <= dist <= 53
173 // 64-bit opt-size=0: 53 <= dist <= 53
174 // 64-bit opt-size=1: 2 <= dist <= 53
175 assert_eq!(2.446494580089078E-296, ieee_parts_to_double(false, 41, 0));
176 check!(2.446494580089078e-296);
177 // 32-bit opt-size=0: 52 <= dist <= 52
178 // 32-bit opt-size=1: 2 <= dist <= 52
179 // 64-bit opt-size=0: 53 <= dist <= 53
180 // 64-bit opt-size=1: 2 <= dist <= 53
181 assert_eq!(
182 4.8929891601781557E-296,
183 ieee_parts_to_double(false, 40, max_mantissa)
184 );
185 check!(4.8929891601781557e-296);
186
187 // 32-bit opt-size=0: 57 <= dist <= 58
188 // 32-bit opt-size=1: 57 <= dist <= 58
189 // 64-bit opt-size=0: 58 <= dist <= 58
190 // 64-bit opt-size=1: 58 <= dist <= 58
191 assert_eq!(1.8014398509481984E16, ieee_parts_to_double(false, 1077, 0));
192 check!(1.8014398509481984e16);
193 // 32-bit opt-size=0: 57 <= dist <= 57
194 // 32-bit opt-size=1: 57 <= dist <= 57
195 // 64-bit opt-size=0: 58 <= dist <= 58
196 // 64-bit opt-size=1: 58 <= dist <= 58
197 assert_eq!(
198 3.6028797018963964E16,
199 ieee_parts_to_double(false, 1076, max_mantissa)
200 );
201 check!(3.6028797018963964e16);
202 // 32-bit opt-size=0: 51 <= dist <= 52
203 // 32-bit opt-size=1: 51 <= dist <= 59
204 // 64-bit opt-size=0: 52 <= dist <= 52
205 // 64-bit opt-size=1: 52 <= dist <= 59
206 assert_eq!(2.900835519859558E-216, ieee_parts_to_double(false, 307, 0));
207 check!(2.900835519859558e-216);
208 // 32-bit opt-size=0: 51 <= dist <= 51
209 // 32-bit opt-size=1: 51 <= dist <= 59
210 // 64-bit opt-size=0: 52 <= dist <= 52
211 // 64-bit opt-size=1: 52 <= dist <= 59
212 assert_eq!(
213 5.801671039719115E-216,
214 ieee_parts_to_double(false, 306, max_mantissa)
215 );
216 check!(5.801671039719115e-216);
217
218 // https://github.com/ulfjack/ryu/commit/19e44d16d80236f5de25800f56d82606d1be00b9#commitcomment-30146483
219 // 32-bit opt-size=0: 49 <= dist <= 49
220 // 32-bit opt-size=1: 44 <= dist <= 49
221 // 64-bit opt-size=0: 50 <= dist <= 50
222 // 64-bit opt-size=1: 44 <= dist <= 50
223 assert_eq!(
224 3.196104012172126E-27,
225 ieee_parts_to_double(false, 934, 0x000FA7161A4D6E0C)
226 );
227 check!(3.196104012172126e-27);
228 }
229
230 #[test]
test_small_integers()231 fn test_small_integers() {
232 check!(9007199254740991.0); // 2^53-1
233 check!(9007199254740992.0); // 2^53
234
235 check!(1.0);
236 check!(12.0);
237 check!(123.0);
238 check!(1234.0);
239 check!(12345.0);
240 check!(123456.0);
241 check!(1234567.0);
242 check!(12345678.0);
243 check!(123456789.0);
244 check!(1234567890.0);
245 check!(1234567895.0);
246 check!(12345678901.0);
247 check!(123456789012.0);
248 check!(1234567890123.0);
249 check!(12345678901234.0);
250 check!(123456789012345.0);
251 check!(1234567890123456.0);
252
253 // 10^i
254 check!(1.0);
255 check!(10.0);
256 check!(100.0);
257 check!(1000.0);
258 check!(10000.0);
259 check!(100000.0);
260 check!(1000000.0);
261 check!(10000000.0);
262 check!(100000000.0);
263 check!(1000000000.0);
264 check!(10000000000.0);
265 check!(100000000000.0);
266 check!(1000000000000.0);
267 check!(10000000000000.0);
268 check!(100000000000000.0);
269 check!(1000000000000000.0);
270
271 // 10^15 + 10^i
272 check!(1000000000000001.0);
273 check!(1000000000000010.0);
274 check!(1000000000000100.0);
275 check!(1000000000001000.0);
276 check!(1000000000010000.0);
277 check!(1000000000100000.0);
278 check!(1000000001000000.0);
279 check!(1000000010000000.0);
280 check!(1000000100000000.0);
281 check!(1000001000000000.0);
282 check!(1000010000000000.0);
283 check!(1000100000000000.0);
284 check!(1001000000000000.0);
285 check!(1010000000000000.0);
286 check!(1100000000000000.0);
287
288 // Largest power of 2 <= 10^(i+1)
289 check!(8.0);
290 check!(64.0);
291 check!(512.0);
292 check!(8192.0);
293 check!(65536.0);
294 check!(524288.0);
295 check!(8388608.0);
296 check!(67108864.0);
297 check!(536870912.0);
298 check!(8589934592.0);
299 check!(68719476736.0);
300 check!(549755813888.0);
301 check!(8796093022208.0);
302 check!(70368744177664.0);
303 check!(562949953421312.0);
304 check!(9007199254740992.0);
305
306 // 1000 * (Largest power of 2 <= 10^(i+1))
307 check!(8000.0);
308 check!(64000.0);
309 check!(512000.0);
310 check!(8192000.0);
311 check!(65536000.0);
312 check!(524288000.0);
313 check!(8388608000.0);
314 check!(67108864000.0);
315 check!(536870912000.0);
316 check!(8589934592000.0);
317 check!(68719476736000.0);
318 check!(549755813888000.0);
319 check!(8796093022208000.0);
320 }
321