1// Copyright 2009 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5package strconv_test 6 7import ( 8 "math" 9 "math/rand" 10 "reflect" 11 . "strconv" 12 "strings" 13 "sync" 14 "testing" 15) 16 17type atofTest struct { 18 in string 19 out string 20 err error 21} 22 23var atoftests = []atofTest{ 24 {"", "0", ErrSyntax}, 25 {"1", "1", nil}, 26 {"+1", "1", nil}, 27 {"1x", "0", ErrSyntax}, 28 {"1.1.", "0", ErrSyntax}, 29 {"1e23", "1e+23", nil}, 30 {"1E23", "1e+23", nil}, 31 {"100000000000000000000000", "1e+23", nil}, 32 {"1e-100", "1e-100", nil}, 33 {"123456700", "1.234567e+08", nil}, 34 {"99999999999999974834176", "9.999999999999997e+22", nil}, 35 {"100000000000000000000001", "1.0000000000000001e+23", nil}, 36 {"100000000000000008388608", "1.0000000000000001e+23", nil}, 37 {"100000000000000016777215", "1.0000000000000001e+23", nil}, 38 {"100000000000000016777216", "1.0000000000000003e+23", nil}, 39 {"-1", "-1", nil}, 40 {"-0.1", "-0.1", nil}, 41 {"-0", "-0", nil}, 42 {"1e-20", "1e-20", nil}, 43 {"625e-3", "0.625", nil}, 44 45 // Hexadecimal floating-point. 46 {"0x1p0", "1", nil}, 47 {"0x1p1", "2", nil}, 48 {"0x1p-1", "0.5", nil}, 49 {"0x1ep-1", "15", nil}, 50 {"-0x1ep-1", "-15", nil}, 51 {"-0x1_ep-1", "-15", nil}, 52 {"0x1p-200", "6.223015277861142e-61", nil}, 53 {"0x1p200", "1.6069380442589903e+60", nil}, 54 {"0x1fFe2.p0", "131042", nil}, 55 {"0x1fFe2.P0", "131042", nil}, 56 {"-0x2p3", "-16", nil}, 57 {"0x0.fp4", "15", nil}, 58 {"0x0.fp0", "0.9375", nil}, 59 {"0x1e2", "0", ErrSyntax}, 60 {"1p2", "0", ErrSyntax}, 61 62 // zeros 63 {"0", "0", nil}, 64 {"0e0", "0", nil}, 65 {"-0e0", "-0", nil}, 66 {"+0e0", "0", nil}, 67 {"0e-0", "0", nil}, 68 {"-0e-0", "-0", nil}, 69 {"+0e-0", "0", nil}, 70 {"0e+0", "0", nil}, 71 {"-0e+0", "-0", nil}, 72 {"+0e+0", "0", nil}, 73 {"0e+01234567890123456789", "0", nil}, 74 {"0.00e-01234567890123456789", "0", nil}, 75 {"-0e+01234567890123456789", "-0", nil}, 76 {"-0.00e-01234567890123456789", "-0", nil}, 77 {"0x0p+01234567890123456789", "0", nil}, 78 {"0x0.00p-01234567890123456789", "0", nil}, 79 {"-0x0p+01234567890123456789", "-0", nil}, 80 {"-0x0.00p-01234567890123456789", "-0", nil}, 81 82 {"0e291", "0", nil}, // issue 15364 83 {"0e292", "0", nil}, // issue 15364 84 {"0e347", "0", nil}, // issue 15364 85 {"0e348", "0", nil}, // issue 15364 86 {"-0e291", "-0", nil}, 87 {"-0e292", "-0", nil}, 88 {"-0e347", "-0", nil}, 89 {"-0e348", "-0", nil}, 90 {"0x0p126", "0", nil}, 91 {"0x0p127", "0", nil}, 92 {"0x0p128", "0", nil}, 93 {"0x0p129", "0", nil}, 94 {"0x0p130", "0", nil}, 95 {"0x0p1022", "0", nil}, 96 {"0x0p1023", "0", nil}, 97 {"0x0p1024", "0", nil}, 98 {"0x0p1025", "0", nil}, 99 {"0x0p1026", "0", nil}, 100 {"-0x0p126", "-0", nil}, 101 {"-0x0p127", "-0", nil}, 102 {"-0x0p128", "-0", nil}, 103 {"-0x0p129", "-0", nil}, 104 {"-0x0p130", "-0", nil}, 105 {"-0x0p1022", "-0", nil}, 106 {"-0x0p1023", "-0", nil}, 107 {"-0x0p1024", "-0", nil}, 108 {"-0x0p1025", "-0", nil}, 109 {"-0x0p1026", "-0", nil}, 110 111 // NaNs 112 {"nan", "NaN", nil}, 113 {"NaN", "NaN", nil}, 114 {"NAN", "NaN", nil}, 115 116 // Infs 117 {"inf", "+Inf", nil}, 118 {"-Inf", "-Inf", nil}, 119 {"+INF", "+Inf", nil}, 120 {"-Infinity", "-Inf", nil}, 121 {"+INFINITY", "+Inf", nil}, 122 {"Infinity", "+Inf", nil}, 123 124 // largest float64 125 {"1.7976931348623157e308", "1.7976931348623157e+308", nil}, 126 {"-1.7976931348623157e308", "-1.7976931348623157e+308", nil}, 127 {"0x1.fffffffffffffp1023", "1.7976931348623157e+308", nil}, 128 {"-0x1.fffffffffffffp1023", "-1.7976931348623157e+308", nil}, 129 {"0x1fffffffffffffp+971", "1.7976931348623157e+308", nil}, 130 {"-0x1fffffffffffffp+971", "-1.7976931348623157e+308", nil}, 131 {"0x.1fffffffffffffp1027", "1.7976931348623157e+308", nil}, 132 {"-0x.1fffffffffffffp1027", "-1.7976931348623157e+308", nil}, 133 134 // next float64 - too large 135 {"1.7976931348623159e308", "+Inf", ErrRange}, 136 {"-1.7976931348623159e308", "-Inf", ErrRange}, 137 {"0x1p1024", "+Inf", ErrRange}, 138 {"-0x1p1024", "-Inf", ErrRange}, 139 {"0x2p1023", "+Inf", ErrRange}, 140 {"-0x2p1023", "-Inf", ErrRange}, 141 {"0x.1p1028", "+Inf", ErrRange}, 142 {"-0x.1p1028", "-Inf", ErrRange}, 143 {"0x.2p1027", "+Inf", ErrRange}, 144 {"-0x.2p1027", "-Inf", ErrRange}, 145 146 // the border is ...158079 147 // borderline - okay 148 {"1.7976931348623158e308", "1.7976931348623157e+308", nil}, 149 {"-1.7976931348623158e308", "-1.7976931348623157e+308", nil}, 150 {"0x1.fffffffffffff7fffp1023", "1.7976931348623157e+308", nil}, 151 {"-0x1.fffffffffffff7fffp1023", "-1.7976931348623157e+308", nil}, 152 // borderline - too large 153 {"1.797693134862315808e308", "+Inf", ErrRange}, 154 {"-1.797693134862315808e308", "-Inf", ErrRange}, 155 {"0x1.fffffffffffff8p1023", "+Inf", ErrRange}, 156 {"-0x1.fffffffffffff8p1023", "-Inf", ErrRange}, 157 {"0x1fffffffffffff.8p+971", "+Inf", ErrRange}, 158 {"-0x1fffffffffffff8p+967", "-Inf", ErrRange}, 159 {"0x.1fffffffffffff8p1027", "+Inf", ErrRange}, 160 {"-0x.1fffffffffffff9p1027", "-Inf", ErrRange}, 161 162 // a little too large 163 {"1e308", "1e+308", nil}, 164 {"2e308", "+Inf", ErrRange}, 165 {"1e309", "+Inf", ErrRange}, 166 {"0x1p1025", "+Inf", ErrRange}, 167 168 // way too large 169 {"1e310", "+Inf", ErrRange}, 170 {"-1e310", "-Inf", ErrRange}, 171 {"1e400", "+Inf", ErrRange}, 172 {"-1e400", "-Inf", ErrRange}, 173 {"1e400000", "+Inf", ErrRange}, 174 {"-1e400000", "-Inf", ErrRange}, 175 {"0x1p1030", "+Inf", ErrRange}, 176 {"0x1p2000", "+Inf", ErrRange}, 177 {"0x1p2000000000", "+Inf", ErrRange}, 178 {"-0x1p1030", "-Inf", ErrRange}, 179 {"-0x1p2000", "-Inf", ErrRange}, 180 {"-0x1p2000000000", "-Inf", ErrRange}, 181 182 // denormalized 183 {"1e-305", "1e-305", nil}, 184 {"1e-306", "1e-306", nil}, 185 {"1e-307", "1e-307", nil}, 186 {"1e-308", "1e-308", nil}, 187 {"1e-309", "1e-309", nil}, 188 {"1e-310", "1e-310", nil}, 189 {"1e-322", "1e-322", nil}, 190 // smallest denormal 191 {"5e-324", "5e-324", nil}, 192 {"4e-324", "5e-324", nil}, 193 {"3e-324", "5e-324", nil}, 194 // too small 195 {"2e-324", "0", nil}, 196 // way too small 197 {"1e-350", "0", nil}, 198 {"1e-400000", "0", nil}, 199 200 // Near denormals and denormals. 201 {"0x2.00000000000000p-1010", "1.8227805048890994e-304", nil}, // 0x00e0000000000000 202 {"0x1.fffffffffffff0p-1010", "1.8227805048890992e-304", nil}, // 0x00dfffffffffffff 203 {"0x1.fffffffffffff7p-1010", "1.8227805048890992e-304", nil}, // rounded down 204 {"0x1.fffffffffffff8p-1010", "1.8227805048890994e-304", nil}, // rounded up 205 {"0x1.fffffffffffff9p-1010", "1.8227805048890994e-304", nil}, // rounded up 206 207 {"0x2.00000000000000p-1022", "4.450147717014403e-308", nil}, // 0x0020000000000000 208 {"0x1.fffffffffffff0p-1022", "4.4501477170144023e-308", nil}, // 0x001fffffffffffff 209 {"0x1.fffffffffffff7p-1022", "4.4501477170144023e-308", nil}, // rounded down 210 {"0x1.fffffffffffff8p-1022", "4.450147717014403e-308", nil}, // rounded up 211 {"0x1.fffffffffffff9p-1022", "4.450147717014403e-308", nil}, // rounded up 212 213 {"0x1.00000000000000p-1022", "2.2250738585072014e-308", nil}, // 0x0010000000000000 214 {"0x0.fffffffffffff0p-1022", "2.225073858507201e-308", nil}, // 0x000fffffffffffff 215 {"0x0.ffffffffffffe0p-1022", "2.2250738585072004e-308", nil}, // 0x000ffffffffffffe 216 {"0x0.ffffffffffffe7p-1022", "2.2250738585072004e-308", nil}, // rounded down 217 {"0x1.ffffffffffffe8p-1023", "2.225073858507201e-308", nil}, // rounded up 218 {"0x1.ffffffffffffe9p-1023", "2.225073858507201e-308", nil}, // rounded up 219 220 {"0x0.00000003fffff0p-1022", "2.072261e-317", nil}, // 0x00000000003fffff 221 {"0x0.00000003456780p-1022", "1.694649e-317", nil}, // 0x0000000000345678 222 {"0x0.00000003456787p-1022", "1.694649e-317", nil}, // rounded down 223 {"0x0.00000003456788p-1022", "1.694649e-317", nil}, // rounded down (half to even) 224 {"0x0.00000003456790p-1022", "1.6946496e-317", nil}, // 0x0000000000345679 225 {"0x0.00000003456789p-1022", "1.6946496e-317", nil}, // rounded up 226 227 {"0x0.0000000345678800000000000000000000000001p-1022", "1.6946496e-317", nil}, // rounded up 228 229 {"0x0.000000000000f0p-1022", "7.4e-323", nil}, // 0x000000000000000f 230 {"0x0.00000000000060p-1022", "3e-323", nil}, // 0x0000000000000006 231 {"0x0.00000000000058p-1022", "3e-323", nil}, // rounded up 232 {"0x0.00000000000057p-1022", "2.5e-323", nil}, // rounded down 233 {"0x0.00000000000050p-1022", "2.5e-323", nil}, // 0x0000000000000005 234 235 {"0x0.00000000000010p-1022", "5e-324", nil}, // 0x0000000000000001 236 {"0x0.000000000000081p-1022", "5e-324", nil}, // rounded up 237 {"0x0.00000000000008p-1022", "0", nil}, // rounded down 238 {"0x0.00000000000007fp-1022", "0", nil}, // rounded down 239 240 // try to overflow exponent 241 {"1e-4294967296", "0", nil}, 242 {"1e+4294967296", "+Inf", ErrRange}, 243 {"1e-18446744073709551616", "0", nil}, 244 {"1e+18446744073709551616", "+Inf", ErrRange}, 245 {"0x1p-4294967296", "0", nil}, 246 {"0x1p+4294967296", "+Inf", ErrRange}, 247 {"0x1p-18446744073709551616", "0", nil}, 248 {"0x1p+18446744073709551616", "+Inf", ErrRange}, 249 250 // Parse errors 251 {"1e", "0", ErrSyntax}, 252 {"1e-", "0", ErrSyntax}, 253 {".e-1", "0", ErrSyntax}, 254 {"1\x00.2", "0", ErrSyntax}, 255 {"0x", "0", ErrSyntax}, 256 {"0x.", "0", ErrSyntax}, 257 {"0x1", "0", ErrSyntax}, 258 {"0x.1", "0", ErrSyntax}, 259 {"0x1p", "0", ErrSyntax}, 260 {"0x.1p", "0", ErrSyntax}, 261 {"0x1p+", "0", ErrSyntax}, 262 {"0x.1p+", "0", ErrSyntax}, 263 {"0x1p-", "0", ErrSyntax}, 264 {"0x.1p-", "0", ErrSyntax}, 265 {"0x1p+2", "4", nil}, 266 {"0x.1p+2", "0.25", nil}, 267 {"0x1p-2", "0.25", nil}, 268 {"0x.1p-2", "0.015625", nil}, 269 270 // https://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308/ 271 {"2.2250738585072012e-308", "2.2250738585072014e-308", nil}, 272 // https://www.exploringbinary.com/php-hangs-on-numeric-value-2-2250738585072011e-308/ 273 {"2.2250738585072011e-308", "2.225073858507201e-308", nil}, 274 275 // A very large number (initially wrongly parsed by the fast algorithm). 276 {"4.630813248087435e+307", "4.630813248087435e+307", nil}, 277 278 // A different kind of very large number. 279 {"22.222222222222222", "22.22222222222222", nil}, 280 {"2." + strings.Repeat("2", 4000) + "e+1", "22.22222222222222", nil}, 281 {"0x1.1111111111111p222", "7.18931911124017e+66", nil}, 282 {"0x2.2222222222222p221", "7.18931911124017e+66", nil}, 283 {"0x2." + strings.Repeat("2", 4000) + "p221", "7.18931911124017e+66", nil}, 284 285 // Exactly halfway between 1 and math.Nextafter(1, 2). 286 // Round to even (down). 287 {"1.00000000000000011102230246251565404236316680908203125", "1", nil}, 288 {"0x1.00000000000008p0", "1", nil}, 289 // Slightly lower; still round down. 290 {"1.00000000000000011102230246251565404236316680908203124", "1", nil}, 291 {"0x1.00000000000007Fp0", "1", nil}, 292 // Slightly higher; round up. 293 {"1.00000000000000011102230246251565404236316680908203126", "1.0000000000000002", nil}, 294 {"0x1.000000000000081p0", "1.0000000000000002", nil}, 295 {"0x1.00000000000009p0", "1.0000000000000002", nil}, 296 // Slightly higher, but you have to read all the way to the end. 297 {"1.00000000000000011102230246251565404236316680908203125" + strings.Repeat("0", 10000) + "1", "1.0000000000000002", nil}, 298 {"0x1.00000000000008" + strings.Repeat("0", 10000) + "1p0", "1.0000000000000002", nil}, 299 300 // Halfway between x := math.Nextafter(1, 2) and math.Nextafter(x, 2) 301 // Round to even (up). 302 {"1.00000000000000033306690738754696212708950042724609375", "1.0000000000000004", nil}, 303 {"0x1.00000000000018p0", "1.0000000000000004", nil}, 304 305 // Halfway between 1090544144181609278303144771584 and 1090544144181609419040633126912 306 // (15497564393479157p+46, should round to even 15497564393479156p+46, issue 36657) 307 {"1090544144181609348671888949248", "1.0905441441816093e+30", nil}, 308 // slightly above, rounds up 309 {"1090544144181609348835077142190", "1.0905441441816094e+30", nil}, 310 311 // Underscores. 312 {"1_23.50_0_0e+1_2", "1.235e+14", nil}, 313 {"-_123.5e+12", "0", ErrSyntax}, 314 {"+_123.5e+12", "0", ErrSyntax}, 315 {"_123.5e+12", "0", ErrSyntax}, 316 {"1__23.5e+12", "0", ErrSyntax}, 317 {"123_.5e+12", "0", ErrSyntax}, 318 {"123._5e+12", "0", ErrSyntax}, 319 {"123.5_e+12", "0", ErrSyntax}, 320 {"123.5__0e+12", "0", ErrSyntax}, 321 {"123.5e_+12", "0", ErrSyntax}, 322 {"123.5e+_12", "0", ErrSyntax}, 323 {"123.5e_-12", "0", ErrSyntax}, 324 {"123.5e-_12", "0", ErrSyntax}, 325 {"123.5e+1__2", "0", ErrSyntax}, 326 {"123.5e+12_", "0", ErrSyntax}, 327 328 {"0x_1_2.3_4_5p+1_2", "74565", nil}, 329 {"-_0x12.345p+12", "0", ErrSyntax}, 330 {"+_0x12.345p+12", "0", ErrSyntax}, 331 {"_0x12.345p+12", "0", ErrSyntax}, 332 {"0x__12.345p+12", "0", ErrSyntax}, 333 {"0x1__2.345p+12", "0", ErrSyntax}, 334 {"0x12_.345p+12", "0", ErrSyntax}, 335 {"0x12._345p+12", "0", ErrSyntax}, 336 {"0x12.3__45p+12", "0", ErrSyntax}, 337 {"0x12.345_p+12", "0", ErrSyntax}, 338 {"0x12.345p_+12", "0", ErrSyntax}, 339 {"0x12.345p+_12", "0", ErrSyntax}, 340 {"0x12.345p_-12", "0", ErrSyntax}, 341 {"0x12.345p-_12", "0", ErrSyntax}, 342 {"0x12.345p+1__2", "0", ErrSyntax}, 343 {"0x12.345p+12_", "0", ErrSyntax}, 344 345 {"1e100x", "0", ErrSyntax}, 346 {"1e1000x", "0", ErrSyntax}, 347} 348 349var atof32tests = []atofTest{ 350 // Hex 351 {"0x1p-100", "7.888609e-31", nil}, 352 {"0x1p100", "1.2676506e+30", nil}, 353 354 // Exactly halfway between 1 and the next float32. 355 // Round to even (down). 356 {"1.000000059604644775390625", "1", nil}, 357 {"0x1.000001p0", "1", nil}, 358 // Slightly lower. 359 {"1.000000059604644775390624", "1", nil}, 360 {"0x1.0000008p0", "1", nil}, 361 {"0x1.000000fp0", "1", nil}, 362 // Slightly higher. 363 {"1.000000059604644775390626", "1.0000001", nil}, 364 {"0x1.000002p0", "1.0000001", nil}, 365 {"0x1.0000018p0", "1.0000001", nil}, 366 {"0x1.0000011p0", "1.0000001", nil}, 367 // Slightly higher, but you have to read all the way to the end. 368 {"1.000000059604644775390625" + strings.Repeat("0", 10000) + "1", "1.0000001", nil}, 369 {"0x1.000001" + strings.Repeat("0", 10000) + "1p0", "1.0000001", nil}, 370 371 // largest float32: (1<<128) * (1 - 2^-24) 372 {"340282346638528859811704183484516925440", "3.4028235e+38", nil}, 373 {"-340282346638528859811704183484516925440", "-3.4028235e+38", nil}, 374 {"0x.ffffffp128", "3.4028235e+38", nil}, 375 {"-340282346638528859811704183484516925440", "-3.4028235e+38", nil}, 376 {"-0x.ffffffp128", "-3.4028235e+38", nil}, 377 // next float32 - too large 378 {"3.4028236e38", "+Inf", ErrRange}, 379 {"-3.4028236e38", "-Inf", ErrRange}, 380 {"0x1.0p128", "+Inf", ErrRange}, 381 {"-0x1.0p128", "-Inf", ErrRange}, 382 // the border is 3.40282356779...e+38 383 // borderline - okay 384 {"3.402823567e38", "3.4028235e+38", nil}, 385 {"-3.402823567e38", "-3.4028235e+38", nil}, 386 {"0x.ffffff7fp128", "3.4028235e+38", nil}, 387 {"-0x.ffffff7fp128", "-3.4028235e+38", nil}, 388 // borderline - too large 389 {"3.4028235678e38", "+Inf", ErrRange}, 390 {"-3.4028235678e38", "-Inf", ErrRange}, 391 {"0x.ffffff8p128", "+Inf", ErrRange}, 392 {"-0x.ffffff8p128", "-Inf", ErrRange}, 393 394 // Denormals: less than 2^-126 395 {"1e-38", "1e-38", nil}, 396 {"1e-39", "1e-39", nil}, 397 {"1e-40", "1e-40", nil}, 398 {"1e-41", "1e-41", nil}, 399 {"1e-42", "1e-42", nil}, 400 {"1e-43", "1e-43", nil}, 401 {"1e-44", "1e-44", nil}, 402 {"6e-45", "6e-45", nil}, // 4p-149 = 5.6e-45 403 {"5e-45", "6e-45", nil}, 404 405 // Smallest denormal 406 {"1e-45", "1e-45", nil}, // 1p-149 = 1.4e-45 407 {"2e-45", "1e-45", nil}, 408 {"3e-45", "3e-45", nil}, 409 410 // Near denormals and denormals. 411 {"0x0.89aBcDp-125", "1.2643093e-38", nil}, // 0x0089abcd 412 {"0x0.8000000p-125", "1.1754944e-38", nil}, // 0x00800000 413 {"0x0.1234560p-125", "1.671814e-39", nil}, // 0x00123456 414 {"0x0.1234567p-125", "1.671814e-39", nil}, // rounded down 415 {"0x0.1234568p-125", "1.671814e-39", nil}, // rounded down 416 {"0x0.1234569p-125", "1.671815e-39", nil}, // rounded up 417 {"0x0.1234570p-125", "1.671815e-39", nil}, // 0x00123457 418 {"0x0.0000010p-125", "1e-45", nil}, // 0x00000001 419 {"0x0.00000081p-125", "1e-45", nil}, // rounded up 420 {"0x0.0000008p-125", "0", nil}, // rounded down 421 {"0x0.0000007p-125", "0", nil}, // rounded down 422 423 // 2^92 = 8388608p+69 = 4951760157141521099596496896 (4.9517602e27) 424 // is an exact power of two that needs 8 decimal digits to be correctly 425 // parsed back. 426 // The float32 before is 16777215p+68 = 4.95175986e+27 427 // The halfway is 4.951760009. A bad algorithm that thinks the previous 428 // float32 is 8388607p+69 will shorten incorrectly to 4.95176e+27. 429 {"4951760157141521099596496896", "4.9517602e+27", nil}, 430} 431 432type atofSimpleTest struct { 433 x float64 434 s string 435} 436 437var ( 438 atofOnce sync.Once 439 atofRandomTests []atofSimpleTest 440 benchmarksRandomBits [1024]string 441 benchmarksRandomNormal [1024]string 442) 443 444func initAtof() { 445 atofOnce.Do(initAtofOnce) 446} 447 448func initAtofOnce() { 449 // The atof routines return NumErrors wrapping 450 // the error and the string. Convert the table above. 451 for i := range atoftests { 452 test := &atoftests[i] 453 if test.err != nil { 454 test.err = &NumError{"ParseFloat", test.in, test.err} 455 } 456 } 457 for i := range atof32tests { 458 test := &atof32tests[i] 459 if test.err != nil { 460 test.err = &NumError{"ParseFloat", test.in, test.err} 461 } 462 } 463 464 // Generate random inputs for tests and benchmarks 465 if testing.Short() { 466 atofRandomTests = make([]atofSimpleTest, 100) 467 } else { 468 atofRandomTests = make([]atofSimpleTest, 10000) 469 } 470 for i := range atofRandomTests { 471 n := uint64(rand.Uint32())<<32 | uint64(rand.Uint32()) 472 x := math.Float64frombits(n) 473 s := FormatFloat(x, 'g', -1, 64) 474 atofRandomTests[i] = atofSimpleTest{x, s} 475 } 476 477 for i := range benchmarksRandomBits { 478 bits := uint64(rand.Uint32())<<32 | uint64(rand.Uint32()) 479 x := math.Float64frombits(bits) 480 benchmarksRandomBits[i] = FormatFloat(x, 'g', -1, 64) 481 } 482 483 for i := range benchmarksRandomNormal { 484 x := rand.NormFloat64() 485 benchmarksRandomNormal[i] = FormatFloat(x, 'g', -1, 64) 486 } 487} 488 489func TestParseFloatPrefix(t *testing.T) { 490 for i := range atoftests { 491 test := &atoftests[i] 492 if test.err != nil { 493 continue 494 } 495 // Adding characters that do not extend a number should not invalidate it. 496 // Test a few. The "i" and "init" cases test that we accept "infi", "infinit" 497 // correctly as "inf" with suffix. 498 for _, suffix := range []string{" ", "q", "+", "-", "<", "=", ">", "(", ")", "i", "init"} { 499 in := test.in + suffix 500 _, n, err := ParseFloatPrefix(in, 64) 501 if err != nil { 502 t.Errorf("ParseFloatPrefix(%q, 64): err = %v; want no error", in, err) 503 } 504 if n != len(test.in) { 505 t.Errorf("ParseFloatPrefix(%q, 64): n = %d; want %d", in, n, len(test.in)) 506 } 507 } 508 } 509} 510 511func testAtof(t *testing.T, opt bool) { 512 initAtof() 513 oldopt := SetOptimize(opt) 514 for i := 0; i < len(atoftests); i++ { 515 test := &atoftests[i] 516 out, err := ParseFloat(test.in, 64) 517 outs := FormatFloat(out, 'g', -1, 64) 518 if outs != test.out || !reflect.DeepEqual(err, test.err) { 519 t.Errorf("ParseFloat(%v, 64) = %v, %v want %v, %v", 520 test.in, out, err, test.out, test.err) 521 } 522 523 if float64(float32(out)) == out { 524 out, err := ParseFloat(test.in, 32) 525 out32 := float32(out) 526 if float64(out32) != out { 527 t.Errorf("ParseFloat(%v, 32) = %v, not a float32 (closest is %v)", test.in, out, float64(out32)) 528 continue 529 } 530 outs := FormatFloat(float64(out32), 'g', -1, 32) 531 if outs != test.out || !reflect.DeepEqual(err, test.err) { 532 t.Errorf("ParseFloat(%v, 32) = %v, %v want %v, %v # %v", 533 test.in, out32, err, test.out, test.err, out) 534 } 535 } 536 } 537 for _, test := range atof32tests { 538 out, err := ParseFloat(test.in, 32) 539 out32 := float32(out) 540 if float64(out32) != out { 541 t.Errorf("ParseFloat(%v, 32) = %v, not a float32 (closest is %v)", test.in, out, float64(out32)) 542 continue 543 } 544 outs := FormatFloat(float64(out32), 'g', -1, 32) 545 if outs != test.out || !reflect.DeepEqual(err, test.err) { 546 t.Errorf("ParseFloat(%v, 32) = %v, %v want %v, %v # %v", 547 test.in, out32, err, test.out, test.err, out) 548 } 549 } 550 SetOptimize(oldopt) 551} 552 553func TestAtof(t *testing.T) { testAtof(t, true) } 554 555func TestAtofSlow(t *testing.T) { testAtof(t, false) } 556 557func TestAtofRandom(t *testing.T) { 558 initAtof() 559 for _, test := range atofRandomTests { 560 x, _ := ParseFloat(test.s, 64) 561 switch { 562 default: 563 t.Errorf("number %s badly parsed as %b (expected %b)", test.s, x, test.x) 564 case x == test.x: 565 case math.IsNaN(test.x) && math.IsNaN(x): 566 } 567 } 568 t.Logf("tested %d random numbers", len(atofRandomTests)) 569} 570 571var roundTripCases = []struct { 572 f float64 573 s string 574}{ 575 // Issue 2917. 576 // This test will break the optimized conversion if the 577 // FPU is using 80-bit registers instead of 64-bit registers, 578 // usually because the operating system initialized the 579 // thread with 80-bit precision and the Go runtime didn't 580 // fix the FP control word. 581 {8865794286000691 << 39, "4.87402195346389e+27"}, 582 {8865794286000692 << 39, "4.8740219534638903e+27"}, 583} 584 585func TestRoundTrip(t *testing.T) { 586 for _, tt := range roundTripCases { 587 old := SetOptimize(false) 588 s := FormatFloat(tt.f, 'g', -1, 64) 589 if s != tt.s { 590 t.Errorf("no-opt FormatFloat(%b) = %s, want %s", tt.f, s, tt.s) 591 } 592 f, err := ParseFloat(tt.s, 64) 593 if f != tt.f || err != nil { 594 t.Errorf("no-opt ParseFloat(%s) = %b, %v want %b, nil", tt.s, f, err, tt.f) 595 } 596 SetOptimize(true) 597 s = FormatFloat(tt.f, 'g', -1, 64) 598 if s != tt.s { 599 t.Errorf("opt FormatFloat(%b) = %s, want %s", tt.f, s, tt.s) 600 } 601 f, err = ParseFloat(tt.s, 64) 602 if f != tt.f || err != nil { 603 t.Errorf("opt ParseFloat(%s) = %b, %v want %b, nil", tt.s, f, err, tt.f) 604 } 605 SetOptimize(old) 606 } 607} 608 609// TestRoundTrip32 tries a fraction of all finite positive float32 values. 610func TestRoundTrip32(t *testing.T) { 611 step := uint32(997) 612 if testing.Short() { 613 step = 99991 614 } 615 count := 0 616 for i := uint32(0); i < 0xff<<23; i += step { 617 f := math.Float32frombits(i) 618 if i&1 == 1 { 619 f = -f // negative 620 } 621 s := FormatFloat(float64(f), 'g', -1, 32) 622 623 parsed, err := ParseFloat(s, 32) 624 parsed32 := float32(parsed) 625 switch { 626 case err != nil: 627 t.Errorf("ParseFloat(%q, 32) gave error %s", s, err) 628 case float64(parsed32) != parsed: 629 t.Errorf("ParseFloat(%q, 32) = %v, not a float32 (nearest is %v)", s, parsed, parsed32) 630 case parsed32 != f: 631 t.Errorf("ParseFloat(%q, 32) = %b (expected %b)", s, parsed32, f) 632 } 633 count++ 634 } 635 t.Logf("tested %d float32's", count) 636} 637 638// Issue 42297: a lot of code in the wild accidentally calls ParseFloat(s, 10) 639// or ParseFloat(s, 0), so allow bitSize values other than 32 and 64. 640func TestParseFloatIncorrectBitSize(t *testing.T) { 641 const s = "1.5e308" 642 const want = 1.5e308 643 644 for _, bitSize := range []int{0, 10, 100, 128} { 645 f, err := ParseFloat(s, bitSize) 646 if err != nil { 647 t.Fatalf("ParseFloat(%q, %d) gave error %s", s, bitSize, err) 648 } 649 if f != want { 650 t.Fatalf("ParseFloat(%q, %d) = %g (expected %g)", s, bitSize, f, want) 651 } 652 } 653} 654 655func BenchmarkAtof64Decimal(b *testing.B) { 656 for i := 0; i < b.N; i++ { 657 ParseFloat("33909", 64) 658 } 659} 660 661func BenchmarkAtof64Float(b *testing.B) { 662 for i := 0; i < b.N; i++ { 663 ParseFloat("339.7784", 64) 664 } 665} 666 667func BenchmarkAtof64FloatExp(b *testing.B) { 668 for i := 0; i < b.N; i++ { 669 ParseFloat("-5.09e75", 64) 670 } 671} 672 673func BenchmarkAtof64Big(b *testing.B) { 674 for i := 0; i < b.N; i++ { 675 ParseFloat("123456789123456789123456789", 64) 676 } 677} 678 679func BenchmarkAtof64RandomBits(b *testing.B) { 680 initAtof() 681 b.ResetTimer() 682 for i := 0; i < b.N; i++ { 683 ParseFloat(benchmarksRandomBits[i%1024], 64) 684 } 685} 686 687func BenchmarkAtof64RandomFloats(b *testing.B) { 688 initAtof() 689 b.ResetTimer() 690 for i := 0; i < b.N; i++ { 691 ParseFloat(benchmarksRandomNormal[i%1024], 64) 692 } 693} 694 695func BenchmarkAtof64RandomLongFloats(b *testing.B) { 696 initAtof() 697 samples := make([]string, len(atofRandomTests)) 698 for i, t := range atofRandomTests { 699 samples[i] = FormatFloat(t.x, 'g', 20, 64) 700 } 701 b.ResetTimer() 702 idx := 0 703 for i := 0; i < b.N; i++ { 704 ParseFloat(samples[idx], 64) 705 idx++ 706 if idx == len(samples) { 707 idx = 0 708 } 709 } 710} 711 712func BenchmarkAtof32Decimal(b *testing.B) { 713 for i := 0; i < b.N; i++ { 714 ParseFloat("33909", 32) 715 } 716} 717 718func BenchmarkAtof32Float(b *testing.B) { 719 for i := 0; i < b.N; i++ { 720 ParseFloat("339.778", 32) 721 } 722} 723 724func BenchmarkAtof32FloatExp(b *testing.B) { 725 for i := 0; i < b.N; i++ { 726 ParseFloat("12.3456e32", 32) 727 } 728} 729 730func BenchmarkAtof32Random(b *testing.B) { 731 n := uint32(997) 732 var float32strings [4096]string 733 for i := range float32strings { 734 n = (99991*n + 42) % (0xff << 23) 735 float32strings[i] = FormatFloat(float64(math.Float32frombits(n)), 'g', -1, 32) 736 } 737 b.ResetTimer() 738 for i := 0; i < b.N; i++ { 739 ParseFloat(float32strings[i%4096], 32) 740 } 741} 742 743func BenchmarkAtof32RandomLong(b *testing.B) { 744 n := uint32(997) 745 var float32strings [4096]string 746 for i := range float32strings { 747 n = (99991*n + 42) % (0xff << 23) 748 float32strings[i] = FormatFloat(float64(math.Float32frombits(n)), 'g', 20, 32) 749 } 750 b.ResetTimer() 751 for i := 0; i < b.N; i++ { 752 ParseFloat(float32strings[i%4096], 32) 753 } 754} 755