1 // Copyright 2010 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.
14 func TestZeroRat(t *testing.T) {
19 t.Errorf("x and y should be both equal and zero")
22 if s := x.String(); s != "0/1" {
23 t.Errorf("got x = %s, want 0/1", s)
26 if s := x.RatString(); s != "0" {
27 t.Errorf("got x = %s, want 0", s)
31 if s := z.RatString(); s != "0" {
32 t.Errorf("got x+y = %s, want 0", s)
36 if s := z.RatString(); s != "0" {
37 t.Errorf("got x-y = %s, want 0", s)
41 if s := z.RatString(); s != "0" {
42 t.Errorf("got x*y = %s, want 0", s)
45 // check for division by zero
47 if s := recover(); s == nil || s.(string) != "division by zero" {
54 var setStringTests = []struct {
65 {in: "1e", ok: false},
66 {in: "1.e", ok: false},
67 {in: "1e+14e-5", ok: false},
68 {in: "1e4.5", ok: false},
70 {in: "a/b", ok: false},
71 {in: "a.b", ok: false},
72 {"-0.1", "-1/10", true},
73 {"-.1", "-1/10", true},
76 {"-1/5", "-1/5", true},
77 {"8129567.7690E14", "812956776900000000000", true},
78 {"78189e+4", "781890000", true},
79 {"553019.8935e+8", "55301989350000", true},
80 {"98765432109876543210987654321e-10", "98765432109876543210987654321/10000000000", true},
81 {"9877861857500000E-7", "3951144743/4", true},
82 {"2169378.417e-3", "2169378417/1000000", true},
83 {"884243222337379604041632732738665534", "884243222337379604041632732738665534", true},
84 {"53/70893980658822810696", "53/70893980658822810696", true},
85 {"106/141787961317645621392", "53/70893980658822810696", true},
86 {"204211327800791583.81095", "4084226556015831676219/20000", true},
89 func TestRatSetString(t *testing.T) {
90 for i, test := range setStringTests {
91 x, ok := new(Rat).SetString(test.in)
95 t.Errorf("#%d SetString(%q) expected failure", i, test.in)
96 } else if x.RatString() != test.out {
97 t.Errorf("#%d SetString(%q) got %s want %s", i, test.in, x.RatString(), test.out)
100 t.Errorf("#%d SetString(%q) got %p want nil", i, test.in, x)
105 func TestRatScan(t *testing.T) {
107 for i, test := range setStringTests {
110 buf.WriteString(test.in)
112 _, err := fmt.Fscanf(&buf, "%v", x)
113 if err == nil != test.ok {
115 t.Errorf("#%d error: %s", i, err)
117 t.Errorf("#%d expected error", i)
121 if err == nil && x.RatString() != test.out {
122 t.Errorf("#%d got %s want %s", i, x.RatString(), test.out)
127 var floatStringTests = []struct {
140 {"-1/3", 3, "-0.333"},
141 {"-2/3", 4, "-0.6667"},
143 {"0.999", 2, "1.00"},
149 func TestFloatString(t *testing.T) {
150 for i, test := range floatStringTests {
151 x, _ := new(Rat).SetString(test.in)
153 if x.FloatString(test.prec) != test.out {
154 t.Errorf("#%d got %s want %s", i, x.FloatString(test.prec), test.out)
159 func TestRatSign(t *testing.T) {
161 for _, a := range setStringTests {
162 x, ok := new(Rat).SetString(a.in)
169 t.Errorf("got %d; want %d for z = %v", s, e, &x)
174 var ratCmpTests = []struct {
183 {"-5/1434770811533343057144", "-5/1434770811533343057145", -1},
184 {"49832350382626108453/8964749413", "49832350382626108454/8964749413", -1},
185 {"-37414950961700930/7204075375675961", "37414950961700930/7204075375675961", -1},
186 {"37414950961700930/7204075375675961", "74829901923401860/14408150751351922", 0},
189 func TestRatCmp(t *testing.T) {
190 for i, test := range ratCmpTests {
191 x, _ := new(Rat).SetString(test.rat1)
192 y, _ := new(Rat).SetString(test.rat2)
196 t.Errorf("#%d got out = %v; want %v", i, out, test.out)
201 func TestIsInt(t *testing.T) {
203 for _, a := range setStringTests {
204 x, ok := new(Rat).SetString(a.in)
209 e := x.Denom().Cmp(one) == 0
211 t.Errorf("got IsInt(%v) == %v; want %v", x, i, e)
216 func TestRatAbs(t *testing.T) {
218 for _, a := range setStringTests {
219 x, ok := new(Rat).SetString(a.in)
229 t.Errorf("got Abs(%v) = %v; want %v", x, z, e)
234 func TestRatNeg(t *testing.T) {
236 for _, a := range setStringTests {
237 x, ok := new(Rat).SetString(a.in)
241 e := new(Rat).Sub(zero, x)
244 t.Errorf("got Neg(%v) = %v; want %v", x, z, e)
249 func TestRatInv(t *testing.T) {
251 for _, a := range setStringTests {
252 x, ok := new(Rat).SetString(a.in)
256 if x.Cmp(zero) == 0 {
257 continue // avoid division by zero
259 e := new(Rat).SetFrac(x.Denom(), x.Num())
262 t.Errorf("got Inv(%v) = %v; want %v", x, z, e)
267 type ratBinFun func(z, x, y *Rat) *Rat
268 type ratBinArg struct {
272 func testRatBin(t *testing.T, i int, name string, f ratBinFun, a ratBinArg) {
273 x, _ := new(Rat).SetString(a.x)
274 y, _ := new(Rat).SetString(a.y)
275 z, _ := new(Rat).SetString(a.z)
276 out := f(new(Rat), x, y)
279 t.Errorf("%s #%d got %s want %s", name, i, out, z)
283 var ratBinTests = []struct {
287 {"0", "0", "0", "0"},
288 {"0", "1", "1", "0"},
289 {"-1", "0", "-1", "0"},
290 {"-1", "1", "0", "-1"},
291 {"1", "1", "2", "1"},
292 {"1/2", "1/2", "1", "1/4"},
293 {"1/4", "1/3", "7/12", "1/12"},
294 {"2/5", "-14/3", "-64/15", "-28/15"},
295 {"4707/49292519774798173060", "-3367/70976135186689855734", "84058377121001851123459/1749296273614329067191168098769082663020", "-1760941/388732505247628681598037355282018369560"},
296 {"-61204110018146728334/3", "-31052192278051565633/2", "-215564796870448153567/6", "950260896245257153059642991192710872711/3"},
297 {"-854857841473707320655/4237645934602118692642972629634714039", "-18/31750379913563777419", "-27/133467566250814981", "15387441146526731771790/134546868362786310073779084329032722548987800600710485341"},
298 {"618575745270541348005638912139/19198433543745179392300736", "-19948846211000086/637313996471", "27674141753240653/30123979153216", "-6169936206128396568797607742807090270137721977/6117715203873571641674006593837351328"},
299 {"-3/26206484091896184128", "5/2848423294177090248", "15310893822118706237/9330894968229805033368778458685147968", "-5/24882386581946146755650075889827061248"},
300 {"26946729/330400702820", "41563965/225583428284", "1238218672302860271/4658307703098666660055", "224002580204097/14906584649915733312176"},
301 {"-8259900599013409474/7", "-84829337473700364773/56707961321161574960", "-468402123685491748914621885145127724451/396955729248131024720", "350340947706464153265156004876107029701/198477864624065512360"},
302 {"575775209696864/1320203974639986246357", "29/712593081308", "410331716733912717985762465/940768218243776489278275419794956", "808/45524274987585732633"},
303 {"1786597389946320496771/2066653520653241", "6269770/1992362624741777", "3559549865190272133656109052308126637/4117523232840525481453983149257", "8967230/3296219033"},
304 {"-36459180403360509753/32150500941194292113930", "9381566963714/9633539", "301622077145533298008420642898530153/309723104686531919656937098270", "-3784609207827/3426986245"},
307 func TestRatBin(t *testing.T) {
308 for i, test := range ratBinTests {
309 arg := ratBinArg{test.x, test.y, test.sum}
310 testRatBin(t, i, "Add", (*Rat).Add, arg)
312 arg = ratBinArg{test.y, test.x, test.sum}
313 testRatBin(t, i, "Add symmetric", (*Rat).Add, arg)
315 arg = ratBinArg{test.sum, test.x, test.y}
316 testRatBin(t, i, "Sub", (*Rat).Sub, arg)
318 arg = ratBinArg{test.sum, test.y, test.x}
319 testRatBin(t, i, "Sub symmetric", (*Rat).Sub, arg)
321 arg = ratBinArg{test.x, test.y, test.prod}
322 testRatBin(t, i, "Mul", (*Rat).Mul, arg)
324 arg = ratBinArg{test.y, test.x, test.prod}
325 testRatBin(t, i, "Mul symmetric", (*Rat).Mul, arg)
328 arg = ratBinArg{test.prod, test.x, test.y}
329 testRatBin(t, i, "Quo", (*Rat).Quo, arg)
333 arg = ratBinArg{test.prod, test.y, test.x}
334 testRatBin(t, i, "Quo symmetric", (*Rat).Quo, arg)
339 func TestIssue820(t *testing.T) {
345 t.Errorf("got %s want %s", z, q)
353 t.Errorf("got %s want %s", z, q)
360 t.Errorf("got %s want %s", z, q)
364 var setFrac64Tests = []struct {
374 {-9223372036854775808, -9223372036854775808, "1"},
377 func TestRatSetFrac64Rat(t *testing.T) {
378 for i, test := range setFrac64Tests {
379 x := new(Rat).SetFrac64(test.a, test.b)
380 if x.RatString() != test.out {
381 t.Errorf("#%d got %s want %s", i, x.RatString(), test.out)
386 func TestRatGobEncoding(t *testing.T) {
387 var medium bytes.Buffer
388 enc := gob.NewEncoder(&medium)
389 dec := gob.NewDecoder(&medium)
390 for i, test := range gobEncodingTests {
391 for j := 0; j < 4; j++ {
392 medium.Reset() // empty buffer for each test case (in case of failures)
400 stest = stest + "." + test
404 if err := enc.Encode(&tx); err != nil {
405 t.Errorf("#%d%c: encoding failed: %s", i, 'a'+j, err)
408 if err := dec.Decode(&rx); err != nil {
409 t.Errorf("#%d%c: decoding failed: %s", i, 'a'+j, err)
411 if rx.Cmp(&tx) != 0 {
412 t.Errorf("#%d%c: transmission failed: got %s want %s", i, 'a'+j, &rx, &tx)
418 func TestIssue2379(t *testing.T) {
422 x.SetFrac(NewInt(3), NewInt(2))
424 t.Errorf("1) got %s want %s", x, q)
427 // 2) aliasing of numerator
429 x.SetFrac(NewInt(3), x.Num())
431 t.Errorf("2) got %s want %s", x, q)
434 // 3) aliasing of denominator
436 x.SetFrac(x.Denom(), NewInt(2))
438 t.Errorf("3) got %s want %s", x, q)
441 // 4) aliasing of numerator and denominator
443 x.SetFrac(x.Denom(), x.Num())
445 t.Errorf("4) got %s want %s", x, q)
448 // 5) numerator and denominator are the same
454 t.Errorf("5) got %s want %s", x, q)