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 #![allow(
22 clippy::approx_constant,
23 clippy::cast_lossless,
24 clippy::float_cmp,
25 clippy::int_plus_one,
26 clippy::non_ascii_literal,
27 clippy::unreadable_literal,
28 clippy::unseparated_literal_suffix
29 )]
30
31 #[macro_use]
32 mod macros;
33
34 use std::f64;
35
pretty(f: f64) -> String36 fn pretty(f: f64) -> String {
37 ryu::Buffer::new().format(f).to_owned()
38 }
39
ieee_parts_to_double(sign: bool, ieee_exponent: u32, ieee_mantissa: u64) -> f6440 fn ieee_parts_to_double(sign: bool, ieee_exponent: u32, ieee_mantissa: u64) -> f64 {
41 assert!(ieee_exponent <= 2047);
42 assert!(ieee_mantissa <= (1u64 << 53) - 1);
43 f64::from_bits(((sign as u64) << 63) | ((ieee_exponent as u64) << 52) | ieee_mantissa)
44 }
45
46 #[test]
test_ryu()47 fn test_ryu() {
48 check!(0.3);
49 check!(1234000000000000.0);
50 check!(1.234e16);
51 check!(2.71828);
52 check!(1.1e128);
53 check!(1.1e-64);
54 check!(2.718281828459045);
55 check!(5e-324);
56 check!(1.7976931348623157e308);
57 }
58
59 #[test]
test_random()60 fn test_random() {
61 let n = if cfg!(miri) { 100 } else { 1000000 };
62 let mut buffer = ryu::Buffer::new();
63 for _ in 0..n {
64 let f: f64 = rand::random();
65 assert_eq!(f, buffer.format_finite(f).parse().unwrap());
66 }
67 }
68
69 #[test]
70 #[cfg_attr(miri, ignore)]
test_non_finite()71 fn test_non_finite() {
72 for i in 0u64..1 << 23 {
73 let f = f64::from_bits((((1 << 11) - 1) << 52) + (i << 29));
74 assert!(!f.is_finite(), "f={}", f);
75 ryu::Buffer::new().format_finite(f);
76 }
77 }
78
79 #[test]
test_basic()80 fn test_basic() {
81 check!(0.0);
82 check!(-0.0);
83 check!(1.0);
84 check!(-1.0);
85 assert_eq!(pretty(f64::NAN.copysign(1.0)), "NaN");
86 assert_eq!(pretty(f64::NAN.copysign(-1.0)), "NaN");
87 assert_eq!(pretty(f64::INFINITY), "inf");
88 assert_eq!(pretty(f64::NEG_INFINITY), "-inf");
89 }
90
91 #[test]
test_switch_to_subnormal()92 fn test_switch_to_subnormal() {
93 check!(2.2250738585072014e-308);
94 }
95
96 #[test]
test_min_and_max()97 fn test_min_and_max() {
98 assert_eq!(f64::from_bits(0x7fefffffffffffff), 1.7976931348623157e308);
99 check!(1.7976931348623157e308);
100 assert_eq!(f64::from_bits(1), 5e-324);
101 check!(5e-324);
102 }
103
104 #[test]
test_lots_of_trailing_zeros()105 fn test_lots_of_trailing_zeros() {
106 check!(2.9802322387695312e-8);
107 }
108
109 #[test]
test_regression()110 fn test_regression() {
111 check!(-2.109808898695963e16);
112 check!(4.940656e-318);
113 check!(1.18575755e-316);
114 check!(2.989102097996e-312);
115 check!(9060801153433600.0);
116 check!(4.708356024711512e18);
117 check!(9.409340012568248e18);
118 check!(1.2345678);
119 }
120
121 #[test]
test_looks_like_pow5()122 fn test_looks_like_pow5() {
123 // These numbers have a mantissa that is a multiple of the largest power of
124 // 5 that fits, and an exponent that causes the computation for q to result
125 // in 22, which is a corner case for Ryū.
126 assert_eq!(f64::from_bits(0x4830F0CF064DD592), 5.764607523034235e39);
127 check!(5.764607523034235e39);
128 assert_eq!(f64::from_bits(0x4840F0CF064DD592), 1.152921504606847e40);
129 check!(1.152921504606847e40);
130 assert_eq!(f64::from_bits(0x4850F0CF064DD592), 2.305843009213694e40);
131 check!(2.305843009213694e40);
132 }
133
134 #[test]
test_output_length()135 fn test_output_length() {
136 check!(1.0); // already tested in Basic
137 check!(1.2);
138 check!(1.23);
139 check!(1.234);
140 check!(1.2345);
141 check!(1.23456);
142 check!(1.234567);
143 check!(1.2345678); // already tested in Regression
144 check!(1.23456789);
145 check!(1.234567895); // 1.234567890 would be trimmed
146 check!(1.2345678901);
147 check!(1.23456789012);
148 check!(1.234567890123);
149 check!(1.2345678901234);
150 check!(1.23456789012345);
151 check!(1.234567890123456);
152 check!(1.2345678901234567);
153
154 // Test 32-bit chunking
155 check!(4.294967294); // 2^32 - 2
156 check!(4.294967295); // 2^32 - 1
157 check!(4.294967296); // 2^32
158 check!(4.294967297); // 2^32 + 1
159 check!(4.294967298); // 2^32 + 2
160 }
161
162 // Test min, max shift values in shiftright128
163 #[test]
test_min_max_shift()164 fn test_min_max_shift() {
165 let max_mantissa = (1u64 << 53) - 1;
166
167 // 32-bit opt-size=0: 49 <= dist <= 50
168 // 32-bit opt-size=1: 30 <= dist <= 50
169 // 64-bit opt-size=0: 50 <= dist <= 50
170 // 64-bit opt-size=1: 30 <= dist <= 50
171 assert_eq!(1.7800590868057611E-307, ieee_parts_to_double(false, 4, 0));
172 check!(1.7800590868057611e-307);
173 // 32-bit opt-size=0: 49 <= dist <= 49
174 // 32-bit opt-size=1: 28 <= dist <= 49
175 // 64-bit opt-size=0: 50 <= dist <= 50
176 // 64-bit opt-size=1: 28 <= dist <= 50
177 assert_eq!(
178 2.8480945388892175E-306,
179 ieee_parts_to_double(false, 6, max_mantissa)
180 );
181 check!(2.8480945388892175e-306);
182 // 32-bit opt-size=0: 52 <= dist <= 53
183 // 32-bit opt-size=1: 2 <= dist <= 53
184 // 64-bit opt-size=0: 53 <= dist <= 53
185 // 64-bit opt-size=1: 2 <= dist <= 53
186 assert_eq!(2.446494580089078E-296, ieee_parts_to_double(false, 41, 0));
187 check!(2.446494580089078e-296);
188 // 32-bit opt-size=0: 52 <= dist <= 52
189 // 32-bit opt-size=1: 2 <= dist <= 52
190 // 64-bit opt-size=0: 53 <= dist <= 53
191 // 64-bit opt-size=1: 2 <= dist <= 53
192 assert_eq!(
193 4.8929891601781557E-296,
194 ieee_parts_to_double(false, 40, max_mantissa)
195 );
196 check!(4.8929891601781557e-296);
197
198 // 32-bit opt-size=0: 57 <= dist <= 58
199 // 32-bit opt-size=1: 57 <= dist <= 58
200 // 64-bit opt-size=0: 58 <= dist <= 58
201 // 64-bit opt-size=1: 58 <= dist <= 58
202 assert_eq!(1.8014398509481984E16, ieee_parts_to_double(false, 1077, 0));
203 check!(1.8014398509481984e16);
204 // 32-bit opt-size=0: 57 <= dist <= 57
205 // 32-bit opt-size=1: 57 <= dist <= 57
206 // 64-bit opt-size=0: 58 <= dist <= 58
207 // 64-bit opt-size=1: 58 <= dist <= 58
208 assert_eq!(
209 3.6028797018963964E16,
210 ieee_parts_to_double(false, 1076, max_mantissa)
211 );
212 check!(3.6028797018963964e16);
213 // 32-bit opt-size=0: 51 <= dist <= 52
214 // 32-bit opt-size=1: 51 <= dist <= 59
215 // 64-bit opt-size=0: 52 <= dist <= 52
216 // 64-bit opt-size=1: 52 <= dist <= 59
217 assert_eq!(2.900835519859558E-216, ieee_parts_to_double(false, 307, 0));
218 check!(2.900835519859558e-216);
219 // 32-bit opt-size=0: 51 <= dist <= 51
220 // 32-bit opt-size=1: 51 <= dist <= 59
221 // 64-bit opt-size=0: 52 <= dist <= 52
222 // 64-bit opt-size=1: 52 <= dist <= 59
223 assert_eq!(
224 5.801671039719115E-216,
225 ieee_parts_to_double(false, 306, max_mantissa)
226 );
227 check!(5.801671039719115e-216);
228
229 // https://github.com/ulfjack/ryu/commit/19e44d16d80236f5de25800f56d82606d1be00b9#commitcomment-30146483
230 // 32-bit opt-size=0: 49 <= dist <= 49
231 // 32-bit opt-size=1: 44 <= dist <= 49
232 // 64-bit opt-size=0: 50 <= dist <= 50
233 // 64-bit opt-size=1: 44 <= dist <= 50
234 assert_eq!(
235 3.196104012172126E-27,
236 ieee_parts_to_double(false, 934, 0x000FA7161A4D6E0C)
237 );
238 check!(3.196104012172126e-27);
239 }
240
241 #[test]
test_small_integers()242 fn test_small_integers() {
243 check!(9007199254740991.0); // 2^53-1
244 check!(9007199254740992.0); // 2^53
245
246 check!(1.0);
247 check!(12.0);
248 check!(123.0);
249 check!(1234.0);
250 check!(12345.0);
251 check!(123456.0);
252 check!(1234567.0);
253 check!(12345678.0);
254 check!(123456789.0);
255 check!(1234567890.0);
256 check!(1234567895.0);
257 check!(12345678901.0);
258 check!(123456789012.0);
259 check!(1234567890123.0);
260 check!(12345678901234.0);
261 check!(123456789012345.0);
262 check!(1234567890123456.0);
263
264 // 10^i
265 check!(1.0);
266 check!(10.0);
267 check!(100.0);
268 check!(1000.0);
269 check!(10000.0);
270 check!(100000.0);
271 check!(1000000.0);
272 check!(10000000.0);
273 check!(100000000.0);
274 check!(1000000000.0);
275 check!(10000000000.0);
276 check!(100000000000.0);
277 check!(1000000000000.0);
278 check!(10000000000000.0);
279 check!(100000000000000.0);
280 check!(1000000000000000.0);
281
282 // 10^15 + 10^i
283 check!(1000000000000001.0);
284 check!(1000000000000010.0);
285 check!(1000000000000100.0);
286 check!(1000000000001000.0);
287 check!(1000000000010000.0);
288 check!(1000000000100000.0);
289 check!(1000000001000000.0);
290 check!(1000000010000000.0);
291 check!(1000000100000000.0);
292 check!(1000001000000000.0);
293 check!(1000010000000000.0);
294 check!(1000100000000000.0);
295 check!(1001000000000000.0);
296 check!(1010000000000000.0);
297 check!(1100000000000000.0);
298
299 // Largest power of 2 <= 10^(i+1)
300 check!(8.0);
301 check!(64.0);
302 check!(512.0);
303 check!(8192.0);
304 check!(65536.0);
305 check!(524288.0);
306 check!(8388608.0);
307 check!(67108864.0);
308 check!(536870912.0);
309 check!(8589934592.0);
310 check!(68719476736.0);
311 check!(549755813888.0);
312 check!(8796093022208.0);
313 check!(70368744177664.0);
314 check!(562949953421312.0);
315 check!(9007199254740992.0);
316
317 // 1000 * (Largest power of 2 <= 10^(i+1))
318 check!(8000.0);
319 check!(64000.0);
320 check!(512000.0);
321 check!(8192000.0);
322 check!(65536000.0);
323 check!(524288000.0);
324 check!(8388608000.0);
325 check!(67108864000.0);
326 check!(536870912000.0);
327 check!(8589934592000.0);
328 check!(68719476736000.0);
329 check!(549755813888000.0);
330 check!(8796093022208000.0);
331 }
332