codekingpro/portable-devtools

1// Copyright 2015 The Go Authors. All rights reserved.2// Use of this source code is governed by a BSD-style3// license that can be found in the LICENSE file.4 5package big6 7import (8	"bytes"9	"encoding/gob"10	"encoding/json"11	"io"12	"strings"13	"testing"14)15 16var floatVals = []string{17	"0",18	"1",19	"0.1",20	"2.71828",21	"1234567890",22	"3.14e1234",23	"3.14e-1234",24	"0.738957395793475734757349579759957975985497e100",25	"0.73895739579347546656564656573475734957975995797598589749859834759476745986795497e100",26	"inf",27	"Inf",28}29 30func TestFloatGobEncoding(t *testing.T) {31	var medium bytes.Buffer32	enc := gob.NewEncoder(&medium)33	dec := gob.NewDecoder(&medium)34	for _, test := range floatVals {35		for _, sign := range []string{"", "+", "-"} {36			for _, prec := range []uint{0, 1, 2, 10, 53, 64, 100, 1000} {37				for _, mode := range []RoundingMode{ToNearestEven, ToNearestAway, ToZero, AwayFromZero, ToNegativeInf, ToPositiveInf} {38					medium.Reset() // empty buffer for each test case (in case of failures)39					x := sign + test40 41					var tx Float42					_, _, err := tx.SetPrec(prec).SetMode(mode).Parse(x, 0)43					if err != nil {44						t.Errorf("parsing of %s (%dbits, %v) failed (invalid test case): %v", x, prec, mode, err)45						continue46					}47 48					// If tx was set to prec == 0, tx.Parse(x, 0) assumes precision 64. Correct it.49					if prec == 0 {50						tx.SetPrec(0)51					}52 53					if err := enc.Encode(&tx); err != nil {54						t.Errorf("encoding of %v (%dbits, %v) failed: %v", &tx, prec, mode, err)55						continue56					}57 58					var rx Float59					if err := dec.Decode(&rx); err != nil {60						t.Errorf("decoding of %v (%dbits, %v) failed: %v", &tx, prec, mode, err)61						continue62					}63 64					if rx.Cmp(&tx) != 0 {65						t.Errorf("transmission of %s failed: got %s want %s", x, rx.String(), tx.String())66						continue67					}68 69					if rx.Prec() != prec {70						t.Errorf("transmission of %s's prec failed: got %d want %d", x, rx.Prec(), prec)71					}72 73					if rx.Mode() != mode {74						t.Errorf("transmission of %s's mode failed: got %s want %s", x, rx.Mode(), mode)75					}76 77					if rx.Acc() != tx.Acc() {78						t.Errorf("transmission of %s's accuracy failed: got %s want %s", x, rx.Acc(), tx.Acc())79					}80				}81			}82		}83	}84}85 86func TestFloatCorruptGob(t *testing.T) {87	var buf bytes.Buffer88	tx := NewFloat(4 / 3).SetPrec(1000).SetMode(ToPositiveInf)89	if err := gob.NewEncoder(&buf).Encode(tx); err != nil {90		t.Fatal(err)91	}92	b := buf.Bytes()93 94	var rx Float95	if err := gob.NewDecoder(bytes.NewReader(b)).Decode(&rx); err != nil {96		t.Fatal(err)97	}98 99	if err := gob.NewDecoder(bytes.NewReader(b[:10])).Decode(&rx); err != io.ErrUnexpectedEOF {100		t.Errorf("got %v want EOF", err)101	}102 103	b[1] = 0104	if err := gob.NewDecoder(bytes.NewReader(b)).Decode(&rx); err == nil {105		t.Fatal("got nil want version error")106	}107}108 109func TestFloatJSONEncoding(t *testing.T) {110	for _, test := range floatVals {111		for _, sign := range []string{"", "+", "-"} {112			for _, prec := range []uint{0, 1, 2, 10, 53, 64, 100, 1000} {113				if prec > 53 && testing.Short() {114					continue115				}116				x := sign + test117				var tx Float118				_, _, err := tx.SetPrec(prec).Parse(x, 0)119				if err != nil {120					t.Errorf("parsing of %s (prec = %d) failed (invalid test case): %v", x, prec, err)121					continue122				}123				b, err := json.Marshal(&tx)124				if err != nil {125					t.Errorf("marshaling of %v (prec = %d) failed: %v", &tx, prec, err)126					continue127				}128				var rx Float129				rx.SetPrec(prec)130				if err := json.Unmarshal(b, &rx); err != nil {131					t.Errorf("unmarshaling of %v (prec = %d) failed: %v", &tx, prec, err)132					continue133				}134				if rx.Cmp(&tx) != 0 {135					t.Errorf("JSON encoding of %v (prec = %d) failed: got %v want %v", &tx, prec, &rx, &tx)136				}137			}138		}139	}140}141 142func TestFloatGobDecodeShortBuffer(t *testing.T) {143	for _, tc := range [][]byte{144		[]byte{0x1, 0x0, 0x0, 0x0},145		[]byte{0x1, 0xfa, 0x0, 0x0, 0x0, 0x0},146	} {147		err := NewFloat(0).GobDecode(tc)148		if err == nil {149			t.Error("expected GobDecode to return error for malformed input")150		}151	}152}153 154func TestFloatGobDecodeInvalid(t *testing.T) {155	for _, tc := range []struct {156		buf []byte157		msg string158	}{159		{160			[]byte{0x1, 0x2a, 0x20, 0x20, 0x20, 0x20, 0x0, 0x20, 0x20, 0x20, 0x0, 0x20, 0x20, 0x20, 0x20, 0x0, 0x0, 0x0, 0x0, 0xc},161			"Float.GobDecode: msb not set in last word",162		},163		{164			[]byte{1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0},165			"Float.GobDecode: nonzero finite number with empty mantissa",166		},167	} {168		err := NewFloat(0).GobDecode(tc.buf)169		if err == nil || !strings.HasPrefix(err.Error(), tc.msg) {170			t.Errorf("expected GobDecode error prefix: %s, got: %v", tc.msg, err)171		}172	}173}174 175func TestFloatAppendText(t *testing.T) {176	for _, test := range floatVals {177		for _, sign := range []string{"", "+", "-"} {178			for _, prec := range []uint{0, 1, 2, 10, 53, 64, 100, 1000} {179				if prec > 53 && testing.Short() {180					continue181				}182				x := sign + test183				var tx Float184				_, _, err := tx.SetPrec(prec).Parse(x, 0)185				if err != nil {186					t.Errorf("parsing of %s (prec = %d) failed (invalid test case): %v", x, prec, err)187					continue188				}189				buf := make([]byte, 4, 32)190				b, err := tx.AppendText(buf)191				if err != nil {192					t.Errorf("marshaling of %v (prec = %d) failed: %v", &tx, prec, err)193					continue194				}195				var rx Float196				rx.SetPrec(prec)197				if err := rx.UnmarshalText(b[4:]); err != nil {198					t.Errorf("unmarshaling of %v (prec = %d) failed: %v", &tx, prec, err)199					continue200				}201				if rx.Cmp(&tx) != 0 {202					t.Errorf("AppendText of %v (prec = %d) failed: got %v want %v", &tx, prec, &rx, &tx)203				}204			}205		}206	}207}208 209func TestFloatAppendTextNil(t *testing.T) {210	var x *Float211	buf := make([]byte, 4, 16)212	data, _ := x.AppendText(buf)213	if string(data[4:]) != "<nil>" {214		t.Errorf("got %q, want <nil>", data[4:])215	}216}217