1 // Copyright 2015 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 5 package big 6 7 import ( 8 "io" 9 "strings" 10 "testing" 11 ) 12 13 func toString(x nat, charset string) string { 14 base := len(charset) 15 16 // special cases 17 switch { 18 case base < 2: 19 panic("illegal base") 20 case len(x) == 0: 21 return string(charset[0]) 22 } 23 24 // allocate buffer for conversion 25 i := x.bitLen()/log2(Word(base)) + 1 // +1: round up 26 s := make([]byte, i) 27 28 // don't destroy x 29 q := nat(nil).set(x) 30 31 // convert 32 for len(q) > 0 { 33 i-- 34 var r Word 35 q, r = q.divW(q, Word(base)) 36 s[i] = charset[r] 37 } 38 39 return string(s[i:]) 40 } 41 42 var strTests = []struct { 43 x nat // nat value to be converted 44 c string // conversion charset 45 s string // expected result 46 }{ 47 {nil, "01", "0"}, 48 {nat{1}, "01", "1"}, 49 {nat{0xc5}, "01", "11000101"}, 50 {nat{03271}, lowercaseDigits[:8], "3271"}, 51 {nat{10}, lowercaseDigits[:10], "10"}, 52 {nat{1234567890}, uppercaseDigits[:10], "1234567890"}, 53 {nat{0xdeadbeef}, lowercaseDigits[:16], "deadbeef"}, 54 {nat{0xdeadbeef}, uppercaseDigits[:16], "DEADBEEF"}, 55 {nat{0x229be7}, lowercaseDigits[:17], "1a2b3c"}, 56 {nat{0x309663e6}, uppercaseDigits[:32], "O9COV6"}, 57 } 58 59 func TestString(t *testing.T) { 60 // test invalid character set explicitly 61 var panicStr string 62 func() { 63 defer func() { 64 panicStr = recover().(string) 65 }() 66 natOne.string("0") 67 }() 68 if panicStr != "invalid character set length" { 69 t.Errorf("expected panic for invalid character set") 70 } 71 72 for _, a := range strTests { 73 s := a.x.string(a.c) 74 if s != a.s { 75 t.Errorf("string%+v\n\tgot s = %s; want %s", a, s, a.s) 76 } 77 78 x, b, _, err := nat(nil).scan(strings.NewReader(a.s), len(a.c), false) 79 if x.cmp(a.x) != 0 { 80 t.Errorf("scan%+v\n\tgot z = %v; want %v", a, x, a.x) 81 } 82 if b != len(a.c) { 83 t.Errorf("scan%+v\n\tgot b = %d; want %d", a, b, len(a.c)) 84 } 85 if err != nil { 86 t.Errorf("scan%+v\n\tgot error = %s", a, err) 87 } 88 } 89 } 90 91 var natScanTests = []struct { 92 s string // string to be scanned 93 base int // input base 94 frac bool // fraction ok 95 x nat // expected nat 96 b int // expected base 97 count int // expected digit count 98 ok bool // expected success 99 next rune // next character (or 0, if at EOF) 100 }{ 101 // error: no mantissa 102 {}, 103 {s: "?"}, 104 {base: 10}, 105 {base: 36}, 106 {s: "?", base: 10}, 107 {s: "0x"}, 108 {s: "345", base: 2}, 109 110 // error: incorrect use of decimal point 111 {s: ".0"}, 112 {s: ".0", base: 10}, 113 {s: ".", base: 0}, 114 {s: "0x.0"}, 115 116 // no errors 117 {"0", 0, false, nil, 10, 1, true, 0}, 118 {"0", 10, false, nil, 10, 1, true, 0}, 119 {"0", 36, false, nil, 36, 1, true, 0}, 120 {"1", 0, false, nat{1}, 10, 1, true, 0}, 121 {"1", 10, false, nat{1}, 10, 1, true, 0}, 122 {"0 ", 0, false, nil, 10, 1, true, ' '}, 123 {"08", 0, false, nil, 10, 1, true, '8'}, 124 {"08", 10, false, nat{8}, 10, 2, true, 0}, 125 {"018", 0, false, nat{1}, 8, 1, true, '8'}, 126 {"0b1", 0, false, nat{1}, 2, 1, true, 0}, 127 {"0b11000101", 0, false, nat{0xc5}, 2, 8, true, 0}, 128 {"03271", 0, false, nat{03271}, 8, 4, true, 0}, 129 {"10ab", 0, false, nat{10}, 10, 2, true, 'a'}, 130 {"1234567890", 0, false, nat{1234567890}, 10, 10, true, 0}, 131 {"xyz", 36, false, nat{(33*36+34)*36 + 35}, 36, 3, true, 0}, 132 {"xyz?", 36, false, nat{(33*36+34)*36 + 35}, 36, 3, true, '?'}, 133 {"0x", 16, false, nil, 16, 1, true, 'x'}, 134 {"0xdeadbeef", 0, false, nat{0xdeadbeef}, 16, 8, true, 0}, 135 {"0XDEADBEEF", 0, false, nat{0xdeadbeef}, 16, 8, true, 0}, 136 137 // no errors, decimal point 138 {"0.", 0, false, nil, 10, 1, true, '.'}, 139 {"0.", 10, true, nil, 10, 0, true, 0}, 140 {"0.1.2", 10, true, nat{1}, 10, -1, true, '.'}, 141 {".000", 10, true, nil, 10, -3, true, 0}, 142 {"12.3", 10, true, nat{123}, 10, -1, true, 0}, 143 {"012.345", 10, true, nat{12345}, 10, -3, true, 0}, 144 } 145 146 func TestScanBase(t *testing.T) { 147 for _, a := range natScanTests { 148 r := strings.NewReader(a.s) 149 x, b, count, err := nat(nil).scan(r, a.base, a.frac) 150 if err == nil && !a.ok { 151 t.Errorf("scan%+v\n\texpected error", a) 152 } 153 if err != nil { 154 if a.ok { 155 t.Errorf("scan%+v\n\tgot error = %s", a, err) 156 } 157 continue 158 } 159 if x.cmp(a.x) != 0 { 160 t.Errorf("scan%+v\n\tgot z = %v; want %v", a, x, a.x) 161 } 162 if b != a.b { 163 t.Errorf("scan%+v\n\tgot b = %d; want %d", a, b, a.base) 164 } 165 if count != a.count { 166 t.Errorf("scan%+v\n\tgot count = %d; want %d", a, count, a.count) 167 } 168 next, _, err := r.ReadRune() 169 if err == io.EOF { 170 next = 0 171 err = nil 172 } 173 if err == nil && next != a.next { 174 t.Errorf("scan%+v\n\tgot next = %q; want %q", a, next, a.next) 175 } 176 } 177 } 178 179 var pi = "3" + 180 "14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651" + 181 "32823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461" + 182 "28475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920" + 183 "96282925409171536436789259036001133053054882046652138414695194151160943305727036575959195309218611738193261179" + 184 "31051185480744623799627495673518857527248912279381830119491298336733624406566430860213949463952247371907021798" + 185 "60943702770539217176293176752384674818467669405132000568127145263560827785771342757789609173637178721468440901" + 186 "22495343014654958537105079227968925892354201995611212902196086403441815981362977477130996051870721134999999837" + 187 "29780499510597317328160963185950244594553469083026425223082533446850352619311881710100031378387528865875332083" + 188 "81420617177669147303598253490428755468731159562863882353787593751957781857780532171226806613001927876611195909" + 189 "21642019893809525720106548586327886593615338182796823030195203530185296899577362259941389124972177528347913151" + 190 "55748572424541506959508295331168617278558890750983817546374649393192550604009277016711390098488240128583616035" + 191 "63707660104710181942955596198946767837449448255379774726847104047534646208046684259069491293313677028989152104" + 192 "75216205696602405803815019351125338243003558764024749647326391419927260426992279678235478163600934172164121992" + 193 "45863150302861829745557067498385054945885869269956909272107975093029553211653449872027559602364806654991198818" + 194 "34797753566369807426542527862551818417574672890977772793800081647060016145249192173217214772350141441973568548" + 195 "16136115735255213347574184946843852332390739414333454776241686251898356948556209921922218427255025425688767179" + 196 "04946016534668049886272327917860857843838279679766814541009538837863609506800642251252051173929848960841284886" + 197 "26945604241965285022210661186306744278622039194945047123713786960956364371917287467764657573962413890865832645" + 198 "99581339047802759009946576407895126946839835259570982582262052248940772671947826848260147699090264013639443745" + 199 "53050682034962524517493996514314298091906592509372216964615157098583874105978859597729754989301617539284681382" + 200 "68683868942774155991855925245953959431049972524680845987273644695848653836736222626099124608051243884390451244" + 201 "13654976278079771569143599770012961608944169486855584840635342207222582848864815845602850601684273945226746767" + 202 "88952521385225499546667278239864565961163548862305774564980355936345681743241125150760694794510965960940252288" + 203 "79710893145669136867228748940560101503308617928680920874760917824938589009714909675985261365549781893129784821" + 204 "68299894872265880485756401427047755513237964145152374623436454285844479526586782105114135473573952311342716610" + 205 "21359695362314429524849371871101457654035902799344037420073105785390621983874478084784896833214457138687519435" + 206 "06430218453191048481005370614680674919278191197939952061419663428754440643745123718192179998391015919561814675" + 207 "14269123974894090718649423196156794520809514655022523160388193014209376213785595663893778708303906979207734672" + 208 "21825625996615014215030680384477345492026054146659252014974428507325186660021324340881907104863317346496514539" + 209 "05796268561005508106658796998163574736384052571459102897064140110971206280439039759515677157700420337869936007" + 210 "23055876317635942187312514712053292819182618612586732157919841484882916447060957527069572209175671167229109816" + 211 "90915280173506712748583222871835209353965725121083579151369882091444210067510334671103141267111369908658516398" + 212 "31501970165151168517143765761835155650884909989859982387345528331635507647918535893226185489632132933089857064" + 213 "20467525907091548141654985946163718027098199430992448895757128289059232332609729971208443357326548938239119325" + 214 "97463667305836041428138830320382490375898524374417029132765618093773444030707469211201913020330380197621101100" + 215 "44929321516084244485963766983895228684783123552658213144957685726243344189303968642624341077322697802807318915" + 216 "44110104468232527162010526522721116603966655730925471105578537634668206531098965269186205647693125705863566201" + 217 "85581007293606598764861179104533488503461136576867532494416680396265797877185560845529654126654085306143444318" + 218 "58676975145661406800700237877659134401712749470420562230538994561314071127000407854733269939081454664645880797" + 219 "27082668306343285878569830523580893306575740679545716377525420211495576158140025012622859413021647155097925923" + 220 "09907965473761255176567513575178296664547791745011299614890304639947132962107340437518957359614589019389713111" + 221 "79042978285647503203198691514028708085990480109412147221317947647772622414254854540332157185306142288137585043" + 222 "06332175182979866223717215916077166925474873898665494945011465406284336639379003976926567214638530673609657120" + 223 "91807638327166416274888800786925602902284721040317211860820419000422966171196377921337575114959501566049631862" + 224 "94726547364252308177036751590673502350728354056704038674351362222477158915049530984448933309634087807693259939" + 225 "78054193414473774418426312986080998886874132604721569516239658645730216315981931951673538129741677294786724229" + 226 "24654366800980676928238280689964004824354037014163149658979409243237896907069779422362508221688957383798623001" + 227 "59377647165122893578601588161755782973523344604281512627203734314653197777416031990665541876397929334419521541" + 228 "34189948544473456738316249934191318148092777710386387734317720754565453220777092120190516609628049092636019759" + 229 "88281613323166636528619326686336062735676303544776280350450777235547105859548702790814356240145171806246436267" + 230 "94561275318134078330336254232783944975382437205835311477119926063813346776879695970309833913077109870408591337" 231 232 // Test case for BenchmarkScanPi. 233 func TestScanPi(t *testing.T) { 234 var x nat 235 z, _, _, err := x.scan(strings.NewReader(pi), 10, false) 236 if err != nil { 237 t.Errorf("scanning pi: %s", err) 238 } 239 if s := z.decimalString(); s != pi { 240 t.Errorf("scanning pi: got %s", s) 241 } 242 } 243 244 func TestScanPiParallel(t *testing.T) { 245 const n = 2 246 c := make(chan int) 247 for i := 0; i < n; i++ { 248 go func() { 249 TestScanPi(t) 250 c <- 0 251 }() 252 } 253 for i := 0; i < n; i++ { 254 <-c 255 } 256 } 257 258 func BenchmarkScanPi(b *testing.B) { 259 for i := 0; i < b.N; i++ { 260 var x nat 261 x.scan(strings.NewReader(pi), 10, false) 262 } 263 } 264 265 func BenchmarkStringPiParallel(b *testing.B) { 266 var x nat 267 x, _, _, _ = x.scan(strings.NewReader(pi), 0, false) 268 if x.decimalString() != pi { 269 panic("benchmark incorrect: conversion failed") 270 } 271 b.RunParallel(func(pb *testing.PB) { 272 for pb.Next() { 273 x.decimalString() 274 } 275 }) 276 } 277 278 func BenchmarkScan10Base2(b *testing.B) { ScanHelper(b, 2, 10, 10) } 279 func BenchmarkScan100Base2(b *testing.B) { ScanHelper(b, 2, 10, 100) } 280 func BenchmarkScan1000Base2(b *testing.B) { ScanHelper(b, 2, 10, 1000) } 281 func BenchmarkScan10000Base2(b *testing.B) { ScanHelper(b, 2, 10, 10000) } 282 func BenchmarkScan100000Base2(b *testing.B) { ScanHelper(b, 2, 10, 100000) } 283 284 func BenchmarkScan10Base8(b *testing.B) { ScanHelper(b, 8, 10, 10) } 285 func BenchmarkScan100Base8(b *testing.B) { ScanHelper(b, 8, 10, 100) } 286 func BenchmarkScan1000Base8(b *testing.B) { ScanHelper(b, 8, 10, 1000) } 287 func BenchmarkScan10000Base8(b *testing.B) { ScanHelper(b, 8, 10, 10000) } 288 func BenchmarkScan100000Base8(b *testing.B) { ScanHelper(b, 8, 10, 100000) } 289 290 func BenchmarkScan10Base10(b *testing.B) { ScanHelper(b, 10, 10, 10) } 291 func BenchmarkScan100Base10(b *testing.B) { ScanHelper(b, 10, 10, 100) } 292 func BenchmarkScan1000Base10(b *testing.B) { ScanHelper(b, 10, 10, 1000) } 293 func BenchmarkScan10000Base10(b *testing.B) { ScanHelper(b, 10, 10, 10000) } 294 func BenchmarkScan100000Base10(b *testing.B) { ScanHelper(b, 10, 10, 100000) } 295 296 func BenchmarkScan10Base16(b *testing.B) { ScanHelper(b, 16, 10, 10) } 297 func BenchmarkScan100Base16(b *testing.B) { ScanHelper(b, 16, 10, 100) } 298 func BenchmarkScan1000Base16(b *testing.B) { ScanHelper(b, 16, 10, 1000) } 299 func BenchmarkScan10000Base16(b *testing.B) { ScanHelper(b, 16, 10, 10000) } 300 func BenchmarkScan100000Base16(b *testing.B) { ScanHelper(b, 16, 10, 100000) } 301 302 func ScanHelper(b *testing.B, base int, x, y Word) { 303 b.StopTimer() 304 var z nat 305 z = z.expWW(x, y) 306 307 var s string 308 s = z.string(lowercaseDigits[:base]) 309 if t := toString(z, lowercaseDigits[:base]); t != s { 310 b.Fatalf("scanning: got %s; want %s", s, t) 311 } 312 b.StartTimer() 313 314 for i := 0; i < b.N; i++ { 315 z.scan(strings.NewReader(s), base, false) 316 } 317 } 318 319 func BenchmarkString10Base2(b *testing.B) { StringHelper(b, 2, 10, 10) } 320 func BenchmarkString100Base2(b *testing.B) { StringHelper(b, 2, 10, 100) } 321 func BenchmarkString1000Base2(b *testing.B) { StringHelper(b, 2, 10, 1000) } 322 func BenchmarkString10000Base2(b *testing.B) { StringHelper(b, 2, 10, 10000) } 323 func BenchmarkString100000Base2(b *testing.B) { StringHelper(b, 2, 10, 100000) } 324 325 func BenchmarkString10Base8(b *testing.B) { StringHelper(b, 8, 10, 10) } 326 func BenchmarkString100Base8(b *testing.B) { StringHelper(b, 8, 10, 100) } 327 func BenchmarkString1000Base8(b *testing.B) { StringHelper(b, 8, 10, 1000) } 328 func BenchmarkString10000Base8(b *testing.B) { StringHelper(b, 8, 10, 10000) } 329 func BenchmarkString100000Base8(b *testing.B) { StringHelper(b, 8, 10, 100000) } 330 331 func BenchmarkString10Base10(b *testing.B) { StringHelper(b, 10, 10, 10) } 332 func BenchmarkString100Base10(b *testing.B) { StringHelper(b, 10, 10, 100) } 333 func BenchmarkString1000Base10(b *testing.B) { StringHelper(b, 10, 10, 1000) } 334 func BenchmarkString10000Base10(b *testing.B) { StringHelper(b, 10, 10, 10000) } 335 func BenchmarkString100000Base10(b *testing.B) { StringHelper(b, 10, 10, 100000) } 336 337 func BenchmarkString10Base16(b *testing.B) { StringHelper(b, 16, 10, 10) } 338 func BenchmarkString100Base16(b *testing.B) { StringHelper(b, 16, 10, 100) } 339 func BenchmarkString1000Base16(b *testing.B) { StringHelper(b, 16, 10, 1000) } 340 func BenchmarkString10000Base16(b *testing.B) { StringHelper(b, 16, 10, 10000) } 341 func BenchmarkString100000Base16(b *testing.B) { StringHelper(b, 16, 10, 100000) } 342 343 func StringHelper(b *testing.B, base int, x, y Word) { 344 b.StopTimer() 345 var z nat 346 z = z.expWW(x, y) 347 z.string(lowercaseDigits[:base]) // warm divisor cache 348 b.StartTimer() 349 350 for i := 0; i < b.N; i++ { 351 _ = z.string(lowercaseDigits[:base]) 352 } 353 } 354 355 func BenchmarkLeafSize0(b *testing.B) { LeafSizeHelper(b, 10, 0) } // test without splitting 356 func BenchmarkLeafSize1(b *testing.B) { LeafSizeHelper(b, 10, 1) } 357 func BenchmarkLeafSize2(b *testing.B) { LeafSizeHelper(b, 10, 2) } 358 func BenchmarkLeafSize3(b *testing.B) { LeafSizeHelper(b, 10, 3) } 359 func BenchmarkLeafSize4(b *testing.B) { LeafSizeHelper(b, 10, 4) } 360 func BenchmarkLeafSize5(b *testing.B) { LeafSizeHelper(b, 10, 5) } 361 func BenchmarkLeafSize6(b *testing.B) { LeafSizeHelper(b, 10, 6) } 362 func BenchmarkLeafSize7(b *testing.B) { LeafSizeHelper(b, 10, 7) } 363 func BenchmarkLeafSize8(b *testing.B) { LeafSizeHelper(b, 10, 8) } 364 func BenchmarkLeafSize9(b *testing.B) { LeafSizeHelper(b, 10, 9) } 365 func BenchmarkLeafSize10(b *testing.B) { LeafSizeHelper(b, 10, 10) } 366 func BenchmarkLeafSize11(b *testing.B) { LeafSizeHelper(b, 10, 11) } 367 func BenchmarkLeafSize12(b *testing.B) { LeafSizeHelper(b, 10, 12) } 368 func BenchmarkLeafSize13(b *testing.B) { LeafSizeHelper(b, 10, 13) } 369 func BenchmarkLeafSize14(b *testing.B) { LeafSizeHelper(b, 10, 14) } 370 func BenchmarkLeafSize15(b *testing.B) { LeafSizeHelper(b, 10, 15) } 371 func BenchmarkLeafSize16(b *testing.B) { LeafSizeHelper(b, 10, 16) } 372 func BenchmarkLeafSize32(b *testing.B) { LeafSizeHelper(b, 10, 32) } // try some large lengths 373 func BenchmarkLeafSize64(b *testing.B) { LeafSizeHelper(b, 10, 64) } 374 375 func LeafSizeHelper(b *testing.B, base Word, size int) { 376 b.StopTimer() 377 originalLeafSize := leafSize 378 resetTable(cacheBase10.table[:]) 379 leafSize = size 380 b.StartTimer() 381 382 for d := 1; d <= 10000; d *= 10 { 383 b.StopTimer() 384 var z nat 385 z = z.expWW(base, Word(d)) // build target number 386 _ = z.string(lowercaseDigits[:base]) // warm divisor cache 387 b.StartTimer() 388 389 for i := 0; i < b.N; i++ { 390 _ = z.string(lowercaseDigits[:base]) 391 } 392 } 393 394 b.StopTimer() 395 resetTable(cacheBase10.table[:]) 396 leafSize = originalLeafSize 397 b.StartTimer() 398 } 399 400 func resetTable(table []divisor) { 401 if table != nil && table[0].bbb != nil { 402 for i := 0; i < len(table); i++ { 403 table[i].bbb = nil 404 table[i].nbits = 0 405 table[i].ndigits = 0 406 } 407 } 408 } 409 410 func TestStringPowers(t *testing.T) { 411 var b, p Word 412 for b = 2; b <= 16; b++ { 413 for p = 0; p <= 512; p++ { 414 x := nat(nil).expWW(b, p) 415 xs := x.string(lowercaseDigits[:b]) 416 xs2 := toString(x, lowercaseDigits[:b]) 417 if xs != xs2 { 418 t.Errorf("failed at %d ** %d in base %d: %s != %s", b, p, b, xs, xs2) 419 } 420 } 421 if b >= 3 && testing.Short() { 422 break 423 } 424 } 425 } 426
