From: Robert Griesemer Date: Fri, 30 Jan 2015 22:25:55 +0000 (-0800) Subject: math/big: split int conversion routines and tests into separate files X-Git-Tag: go1.5beta1~2192 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=a0c5d2840336b74db781757a7d40472ef204a7b9;p=gostls13.git math/big: split int conversion routines and tests into separate files No other functional changes. Change-Id: If0d9e6208d53478e70d991b6926ea196b2cccf2e Reviewed-on: https://go-review.googlesource.com/3672 Reviewed-by: Alan Donovan --- diff --git a/src/math/big/int.go b/src/math/big/int.go index 3a4d227335..5c1b2cd765 100644 --- a/src/math/big/int.go +++ b/src/math/big/int.go @@ -321,221 +321,6 @@ func (x *Int) Cmp(y *Int) (r int) { return } -func (x *Int) String() string { - switch { - case x == nil: - return "" - case x.neg: - return "-" + x.abs.decimalString() - } - return x.abs.decimalString() -} - -func charset(ch rune) string { - switch ch { - case 'b': - return lowercaseDigits[0:2] - case 'o': - return lowercaseDigits[0:8] - case 'd', 's', 'v': - return lowercaseDigits[0:10] - case 'x': - return lowercaseDigits[0:16] - case 'X': - return uppercaseDigits[0:16] - } - return "" // unknown format -} - -// write count copies of text to s -func writeMultiple(s fmt.State, text string, count int) { - if len(text) > 0 { - b := []byte(text) - for ; count > 0; count-- { - s.Write(b) - } - } -} - -// Format is a support routine for fmt.Formatter. It accepts -// the formats 'b' (binary), 'o' (octal), 'd' (decimal), 'x' -// (lowercase hexadecimal), and 'X' (uppercase hexadecimal). -// Also supported are the full suite of package fmt's format -// verbs for integral types, including '+', '-', and ' ' -// for sign control, '#' for leading zero in octal and for -// hexadecimal, a leading "0x" or "0X" for "%#x" and "%#X" -// respectively, specification of minimum digits precision, -// output field width, space or zero padding, and left or -// right justification. -// -func (x *Int) Format(s fmt.State, ch rune) { - cs := charset(ch) - - // special cases - switch { - case cs == "": - // unknown format - fmt.Fprintf(s, "%%!%c(big.Int=%s)", ch, x.String()) - return - case x == nil: - fmt.Fprint(s, "") - return - } - - // determine sign character - sign := "" - switch { - case x.neg: - sign = "-" - case s.Flag('+'): // supersedes ' ' when both specified - sign = "+" - case s.Flag(' '): - sign = " " - } - - // determine prefix characters for indicating output base - prefix := "" - if s.Flag('#') { - switch ch { - case 'o': // octal - prefix = "0" - case 'x': // hexadecimal - prefix = "0x" - case 'X': - prefix = "0X" - } - } - - // determine digits with base set by len(cs) and digit characters from cs - digits := x.abs.string(cs) - - // number of characters for the three classes of number padding - var left int // space characters to left of digits for right justification ("%8d") - var zeroes int // zero characters (actually cs[0]) as left-most digits ("%.8d") - var right int // space characters to right of digits for left justification ("%-8d") - - // determine number padding from precision: the least number of digits to output - precision, precisionSet := s.Precision() - if precisionSet { - switch { - case len(digits) < precision: - zeroes = precision - len(digits) // count of zero padding - case digits == "0" && precision == 0: - return // print nothing if zero value (x == 0) and zero precision ("." or ".0") - } - } - - // determine field pad from width: the least number of characters to output - length := len(sign) + len(prefix) + zeroes + len(digits) - if width, widthSet := s.Width(); widthSet && length < width { // pad as specified - switch d := width - length; { - case s.Flag('-'): - // pad on the right with spaces; supersedes '0' when both specified - right = d - case s.Flag('0') && !precisionSet: - // pad with zeroes unless precision also specified - zeroes = d - default: - // pad on the left with spaces - left = d - } - } - - // print number as [left pad][sign][prefix][zero pad][digits][right pad] - writeMultiple(s, " ", left) - writeMultiple(s, sign, 1) - writeMultiple(s, prefix, 1) - writeMultiple(s, "0", zeroes) - writeMultiple(s, digits, 1) - writeMultiple(s, " ", right) -} - -// scan sets z to the integer value corresponding to the longest possible prefix -// read from r representing a signed integer number in a given conversion base. -// It returns z, the actual conversion base used, and an error, if any. In the -// error case, the value of z is undefined but the returned value is nil. The -// syntax follows the syntax of integer literals in Go. -// -// The base argument must be 0 or a value from 2 through MaxBase. If the base -// is 0, the string prefix determines the actual conversion base. A prefix of -// ``0x'' or ``0X'' selects base 16; the ``0'' prefix selects base 8, and a -// ``0b'' or ``0B'' prefix selects base 2. Otherwise the selected base is 10. -// -func (z *Int) scan(r io.ByteScanner, base int) (*Int, int, error) { - // determine sign - neg, err := scanSign(r) - if err != nil { - return nil, 0, err - } - - // determine mantissa - z.abs, base, _, err = z.abs.scan(r, base, false) - if err != nil { - return nil, base, err - } - z.neg = len(z.abs) > 0 && neg // 0 has no sign - - return z, base, nil -} - -func scanSign(r io.ByteScanner) (neg bool, err error) { - var ch byte - if ch, err = r.ReadByte(); err != nil { - return false, err - } - switch ch { - case '-': - neg = true - case '+': - // nothing to do - default: - r.UnreadByte() - } - return -} - -// byteReader is a local wrapper around fmt.ScanState; -// it implements the ByteReader interface. -type byteReader struct { - fmt.ScanState -} - -func (r byteReader) ReadByte() (byte, error) { - ch, size, err := r.ReadRune() - if size != 1 && err == nil { - err = fmt.Errorf("invalid rune %#U", ch) - } - return byte(ch), err -} - -func (r byteReader) UnreadByte() error { - return r.UnreadRune() -} - -// Scan is a support routine for fmt.Scanner; it sets z to the value of -// the scanned number. It accepts the formats 'b' (binary), 'o' (octal), -// 'd' (decimal), 'x' (lowercase hexadecimal), and 'X' (uppercase hexadecimal). -func (z *Int) Scan(s fmt.ScanState, ch rune) error { - s.SkipSpace() // skip leading space characters - base := 0 - switch ch { - case 'b': - base = 2 - case 'o': - base = 8 - case 'd': - base = 10 - case 'x', 'X': - base = 16 - case 's', 'v': - // let scan determine the base - default: - return errors.New("Int.Scan: invalid verb") - } - _, _, err := z.scan(byteReader{s}, base) - return err -} - // low32 returns the least significant 32 bits of z. func low32(z nat) uint32 { if len(z) == 0 { diff --git a/src/math/big/int_test.go b/src/math/big/int_test.go index d373e842c6..1418dca335 100644 --- a/src/math/big/int_test.go +++ b/src/math/big/int_test.go @@ -219,337 +219,6 @@ func TestMulRangeZ(t *testing.T) { } } -var stringTests = []struct { - in string - out string - base int - val int64 - ok bool -}{ - {in: "", ok: false}, - {in: "a", ok: false}, - {in: "z", ok: false}, - {in: "+", ok: false}, - {in: "-", ok: false}, - {in: "0b", ok: false}, - {in: "0x", ok: false}, - {in: "2", base: 2, ok: false}, - {in: "0b2", base: 0, ok: false}, - {in: "08", ok: false}, - {in: "8", base: 8, ok: false}, - {in: "0xg", base: 0, ok: false}, - {in: "g", base: 16, ok: false}, - {"0", "0", 0, 0, true}, - {"0", "0", 10, 0, true}, - {"0", "0", 16, 0, true}, - {"+0", "0", 0, 0, true}, - {"-0", "0", 0, 0, true}, - {"10", "10", 0, 10, true}, - {"10", "10", 10, 10, true}, - {"10", "10", 16, 16, true}, - {"-10", "-10", 16, -16, true}, - {"+10", "10", 16, 16, true}, - {"0x10", "16", 0, 16, true}, - {in: "0x10", base: 16, ok: false}, - {"-0x10", "-16", 0, -16, true}, - {"+0x10", "16", 0, 16, true}, - {"00", "0", 0, 0, true}, - {"0", "0", 8, 0, true}, - {"07", "7", 0, 7, true}, - {"7", "7", 8, 7, true}, - {"023", "19", 0, 19, true}, - {"23", "23", 8, 19, true}, - {"cafebabe", "cafebabe", 16, 0xcafebabe, true}, - {"0b0", "0", 0, 0, true}, - {"-111", "-111", 2, -7, true}, - {"-0b111", "-7", 0, -7, true}, - {"0b1001010111", "599", 0, 0x257, true}, - {"1001010111", "1001010111", 2, 0x257, true}, -} - -func format(base int) string { - switch base { - case 2: - return "%b" - case 8: - return "%o" - case 16: - return "%x" - } - return "%d" -} - -func TestGetString(t *testing.T) { - z := new(Int) - for i, test := range stringTests { - if !test.ok { - continue - } - z.SetInt64(test.val) - - if test.base == 10 { - s := z.String() - if s != test.out { - t.Errorf("#%da got %s; want %s", i, s, test.out) - } - } - - s := fmt.Sprintf(format(test.base), z) - if s != test.out { - t.Errorf("#%db got %s; want %s", i, s, test.out) - } - } -} - -func TestSetString(t *testing.T) { - tmp := new(Int) - for i, test := range stringTests { - // initialize to a non-zero value so that issues with parsing - // 0 are detected - tmp.SetInt64(1234567890) - n1, ok1 := new(Int).SetString(test.in, test.base) - n2, ok2 := tmp.SetString(test.in, test.base) - expected := NewInt(test.val) - if ok1 != test.ok || ok2 != test.ok { - t.Errorf("#%d (input '%s') ok incorrect (should be %t)", i, test.in, test.ok) - continue - } - if !ok1 { - if n1 != nil { - t.Errorf("#%d (input '%s') n1 != nil", i, test.in) - } - continue - } - if !ok2 { - if n2 != nil { - t.Errorf("#%d (input '%s') n2 != nil", i, test.in) - } - continue - } - - if ok1 && !isNormalized(n1) { - t.Errorf("#%d (input '%s'): %v is not normalized", i, test.in, *n1) - } - if ok2 && !isNormalized(n2) { - t.Errorf("#%d (input '%s'): %v is not normalized", i, test.in, *n2) - } - - if n1.Cmp(expected) != 0 { - t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n1, test.val) - } - if n2.Cmp(expected) != 0 { - t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n2, test.val) - } - } -} - -var formatTests = []struct { - input string - format string - output string -}{ - {"", "%x", ""}, - {"", "%#x", ""}, - {"", "%#y", "%!y(big.Int=)"}, - - {"10", "%b", "1010"}, - {"10", "%o", "12"}, - {"10", "%d", "10"}, - {"10", "%v", "10"}, - {"10", "%x", "a"}, - {"10", "%X", "A"}, - {"-10", "%X", "-A"}, - {"10", "%y", "%!y(big.Int=10)"}, - {"-10", "%y", "%!y(big.Int=-10)"}, - - {"10", "%#b", "1010"}, - {"10", "%#o", "012"}, - {"10", "%#d", "10"}, - {"10", "%#v", "10"}, - {"10", "%#x", "0xa"}, - {"10", "%#X", "0XA"}, - {"-10", "%#X", "-0XA"}, - {"10", "%#y", "%!y(big.Int=10)"}, - {"-10", "%#y", "%!y(big.Int=-10)"}, - - {"1234", "%d", "1234"}, - {"1234", "%3d", "1234"}, - {"1234", "%4d", "1234"}, - {"-1234", "%d", "-1234"}, - {"1234", "% 5d", " 1234"}, - {"1234", "%+5d", "+1234"}, - {"1234", "%-5d", "1234 "}, - {"1234", "%x", "4d2"}, - {"1234", "%X", "4D2"}, - {"-1234", "%3x", "-4d2"}, - {"-1234", "%4x", "-4d2"}, - {"-1234", "%5x", " -4d2"}, - {"-1234", "%-5x", "-4d2 "}, - {"1234", "%03d", "1234"}, - {"1234", "%04d", "1234"}, - {"1234", "%05d", "01234"}, - {"1234", "%06d", "001234"}, - {"-1234", "%06d", "-01234"}, - {"1234", "%+06d", "+01234"}, - {"1234", "% 06d", " 01234"}, - {"1234", "%-6d", "1234 "}, - {"1234", "%-06d", "1234 "}, - {"-1234", "%-06d", "-1234 "}, - - {"1234", "%.3d", "1234"}, - {"1234", "%.4d", "1234"}, - {"1234", "%.5d", "01234"}, - {"1234", "%.6d", "001234"}, - {"-1234", "%.3d", "-1234"}, - {"-1234", "%.4d", "-1234"}, - {"-1234", "%.5d", "-01234"}, - {"-1234", "%.6d", "-001234"}, - - {"1234", "%8.3d", " 1234"}, - {"1234", "%8.4d", " 1234"}, - {"1234", "%8.5d", " 01234"}, - {"1234", "%8.6d", " 001234"}, - {"-1234", "%8.3d", " -1234"}, - {"-1234", "%8.4d", " -1234"}, - {"-1234", "%8.5d", " -01234"}, - {"-1234", "%8.6d", " -001234"}, - - {"1234", "%+8.3d", " +1234"}, - {"1234", "%+8.4d", " +1234"}, - {"1234", "%+8.5d", " +01234"}, - {"1234", "%+8.6d", " +001234"}, - {"-1234", "%+8.3d", " -1234"}, - {"-1234", "%+8.4d", " -1234"}, - {"-1234", "%+8.5d", " -01234"}, - {"-1234", "%+8.6d", " -001234"}, - - {"1234", "% 8.3d", " 1234"}, - {"1234", "% 8.4d", " 1234"}, - {"1234", "% 8.5d", " 01234"}, - {"1234", "% 8.6d", " 001234"}, - {"-1234", "% 8.3d", " -1234"}, - {"-1234", "% 8.4d", " -1234"}, - {"-1234", "% 8.5d", " -01234"}, - {"-1234", "% 8.6d", " -001234"}, - - {"1234", "%.3x", "4d2"}, - {"1234", "%.4x", "04d2"}, - {"1234", "%.5x", "004d2"}, - {"1234", "%.6x", "0004d2"}, - {"-1234", "%.3x", "-4d2"}, - {"-1234", "%.4x", "-04d2"}, - {"-1234", "%.5x", "-004d2"}, - {"-1234", "%.6x", "-0004d2"}, - - {"1234", "%8.3x", " 4d2"}, - {"1234", "%8.4x", " 04d2"}, - {"1234", "%8.5x", " 004d2"}, - {"1234", "%8.6x", " 0004d2"}, - {"-1234", "%8.3x", " -4d2"}, - {"-1234", "%8.4x", " -04d2"}, - {"-1234", "%8.5x", " -004d2"}, - {"-1234", "%8.6x", " -0004d2"}, - - {"1234", "%+8.3x", " +4d2"}, - {"1234", "%+8.4x", " +04d2"}, - {"1234", "%+8.5x", " +004d2"}, - {"1234", "%+8.6x", " +0004d2"}, - {"-1234", "%+8.3x", " -4d2"}, - {"-1234", "%+8.4x", " -04d2"}, - {"-1234", "%+8.5x", " -004d2"}, - {"-1234", "%+8.6x", " -0004d2"}, - - {"1234", "% 8.3x", " 4d2"}, - {"1234", "% 8.4x", " 04d2"}, - {"1234", "% 8.5x", " 004d2"}, - {"1234", "% 8.6x", " 0004d2"}, - {"1234", "% 8.7x", " 00004d2"}, - {"1234", "% 8.8x", " 000004d2"}, - {"-1234", "% 8.3x", " -4d2"}, - {"-1234", "% 8.4x", " -04d2"}, - {"-1234", "% 8.5x", " -004d2"}, - {"-1234", "% 8.6x", " -0004d2"}, - {"-1234", "% 8.7x", "-00004d2"}, - {"-1234", "% 8.8x", "-000004d2"}, - - {"1234", "%-8.3d", "1234 "}, - {"1234", "%-8.4d", "1234 "}, - {"1234", "%-8.5d", "01234 "}, - {"1234", "%-8.6d", "001234 "}, - {"1234", "%-8.7d", "0001234 "}, - {"1234", "%-8.8d", "00001234"}, - {"-1234", "%-8.3d", "-1234 "}, - {"-1234", "%-8.4d", "-1234 "}, - {"-1234", "%-8.5d", "-01234 "}, - {"-1234", "%-8.6d", "-001234 "}, - {"-1234", "%-8.7d", "-0001234"}, - {"-1234", "%-8.8d", "-00001234"}, - - {"16777215", "%b", "111111111111111111111111"}, // 2**24 - 1 - - {"0", "%.d", ""}, - {"0", "%.0d", ""}, - {"0", "%3.d", ""}, -} - -func TestFormat(t *testing.T) { - for i, test := range formatTests { - var x *Int - if test.input != "" { - var ok bool - x, ok = new(Int).SetString(test.input, 0) - if !ok { - t.Errorf("#%d failed reading input %s", i, test.input) - } - } - output := fmt.Sprintf(test.format, x) - if output != test.output { - t.Errorf("#%d got %q; want %q, {%q, %q, %q}", i, output, test.output, test.input, test.format, test.output) - } - } -} - -var scanTests = []struct { - input string - format string - output string - remaining int -}{ - {"1010", "%b", "10", 0}, - {"0b1010", "%v", "10", 0}, - {"12", "%o", "10", 0}, - {"012", "%v", "10", 0}, - {"10", "%d", "10", 0}, - {"10", "%v", "10", 0}, - {"a", "%x", "10", 0}, - {"0xa", "%v", "10", 0}, - {"A", "%X", "10", 0}, - {"-A", "%X", "-10", 0}, - {"+0b1011001", "%v", "89", 0}, - {"0xA", "%v", "10", 0}, - {"0 ", "%v", "0", 1}, - {"2+3", "%v", "2", 2}, - {"0XABC 12", "%v", "2748", 3}, -} - -func TestScan(t *testing.T) { - var buf bytes.Buffer - for i, test := range scanTests { - x := new(Int) - buf.Reset() - buf.WriteString(test.input) - if _, err := fmt.Fscanf(&buf, test.format, x); err != nil { - t.Errorf("#%d error: %s", i, err) - } - if x.String() != test.output { - t.Errorf("#%d got %s; want %s", i, x.String(), test.output) - } - if buf.Len() != test.remaining { - t.Errorf("#%d got %d bytes remaining; want %d", i, buf.Len(), test.remaining) - } - } -} - // Examples from the Go Language Spec, section "Arithmetic operators" var divisionSignsTests = []struct { x, y int64 diff --git a/src/math/big/intconv.go b/src/math/big/intconv.go new file mode 100644 index 0000000000..9c68a22bed --- /dev/null +++ b/src/math/big/intconv.go @@ -0,0 +1,228 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file implements int-to-string conversion functions. + +package big + +import ( + "errors" + "fmt" + "io" +) + +func (x *Int) String() string { + switch { + case x == nil: + return "" + case x.neg: + return "-" + x.abs.decimalString() + } + return x.abs.decimalString() +} + +func charset(ch rune) string { + switch ch { + case 'b': + return lowercaseDigits[0:2] + case 'o': + return lowercaseDigits[0:8] + case 'd', 's', 'v': + return lowercaseDigits[0:10] + case 'x': + return lowercaseDigits[0:16] + case 'X': + return uppercaseDigits[0:16] + } + return "" // unknown format +} + +// write count copies of text to s +func writeMultiple(s fmt.State, text string, count int) { + if len(text) > 0 { + b := []byte(text) + for ; count > 0; count-- { + s.Write(b) + } + } +} + +// Format is a support routine for fmt.Formatter. It accepts +// the formats 'b' (binary), 'o' (octal), 'd' (decimal), 'x' +// (lowercase hexadecimal), and 'X' (uppercase hexadecimal). +// Also supported are the full suite of package fmt's format +// verbs for integral types, including '+', '-', and ' ' +// for sign control, '#' for leading zero in octal and for +// hexadecimal, a leading "0x" or "0X" for "%#x" and "%#X" +// respectively, specification of minimum digits precision, +// output field width, space or zero padding, and left or +// right justification. +// +func (x *Int) Format(s fmt.State, ch rune) { + cs := charset(ch) + + // special cases + switch { + case cs == "": + // unknown format + fmt.Fprintf(s, "%%!%c(big.Int=%s)", ch, x.String()) + return + case x == nil: + fmt.Fprint(s, "") + return + } + + // determine sign character + sign := "" + switch { + case x.neg: + sign = "-" + case s.Flag('+'): // supersedes ' ' when both specified + sign = "+" + case s.Flag(' '): + sign = " " + } + + // determine prefix characters for indicating output base + prefix := "" + if s.Flag('#') { + switch ch { + case 'o': // octal + prefix = "0" + case 'x': // hexadecimal + prefix = "0x" + case 'X': + prefix = "0X" + } + } + + // determine digits with base set by len(cs) and digit characters from cs + digits := x.abs.string(cs) + + // number of characters for the three classes of number padding + var left int // space characters to left of digits for right justification ("%8d") + var zeroes int // zero characters (actually cs[0]) as left-most digits ("%.8d") + var right int // space characters to right of digits for left justification ("%-8d") + + // determine number padding from precision: the least number of digits to output + precision, precisionSet := s.Precision() + if precisionSet { + switch { + case len(digits) < precision: + zeroes = precision - len(digits) // count of zero padding + case digits == "0" && precision == 0: + return // print nothing if zero value (x == 0) and zero precision ("." or ".0") + } + } + + // determine field pad from width: the least number of characters to output + length := len(sign) + len(prefix) + zeroes + len(digits) + if width, widthSet := s.Width(); widthSet && length < width { // pad as specified + switch d := width - length; { + case s.Flag('-'): + // pad on the right with spaces; supersedes '0' when both specified + right = d + case s.Flag('0') && !precisionSet: + // pad with zeroes unless precision also specified + zeroes = d + default: + // pad on the left with spaces + left = d + } + } + + // print number as [left pad][sign][prefix][zero pad][digits][right pad] + writeMultiple(s, " ", left) + writeMultiple(s, sign, 1) + writeMultiple(s, prefix, 1) + writeMultiple(s, "0", zeroes) + writeMultiple(s, digits, 1) + writeMultiple(s, " ", right) +} + +// scan sets z to the integer value corresponding to the longest possible prefix +// read from r representing a signed integer number in a given conversion base. +// It returns z, the actual conversion base used, and an error, if any. In the +// error case, the value of z is undefined but the returned value is nil. The +// syntax follows the syntax of integer literals in Go. +// +// The base argument must be 0 or a value from 2 through MaxBase. If the base +// is 0, the string prefix determines the actual conversion base. A prefix of +// ``0x'' or ``0X'' selects base 16; the ``0'' prefix selects base 8, and a +// ``0b'' or ``0B'' prefix selects base 2. Otherwise the selected base is 10. +// +func (z *Int) scan(r io.ByteScanner, base int) (*Int, int, error) { + // determine sign + neg, err := scanSign(r) + if err != nil { + return nil, 0, err + } + + // determine mantissa + z.abs, base, _, err = z.abs.scan(r, base, false) + if err != nil { + return nil, base, err + } + z.neg = len(z.abs) > 0 && neg // 0 has no sign + + return z, base, nil +} + +func scanSign(r io.ByteScanner) (neg bool, err error) { + var ch byte + if ch, err = r.ReadByte(); err != nil { + return false, err + } + switch ch { + case '-': + neg = true + case '+': + // nothing to do + default: + r.UnreadByte() + } + return +} + +// byteReader is a local wrapper around fmt.ScanState; +// it implements the ByteReader interface. +type byteReader struct { + fmt.ScanState +} + +func (r byteReader) ReadByte() (byte, error) { + ch, size, err := r.ReadRune() + if size != 1 && err == nil { + err = fmt.Errorf("invalid rune %#U", ch) + } + return byte(ch), err +} + +func (r byteReader) UnreadByte() error { + return r.UnreadRune() +} + +// Scan is a support routine for fmt.Scanner; it sets z to the value of +// the scanned number. It accepts the formats 'b' (binary), 'o' (octal), +// 'd' (decimal), 'x' (lowercase hexadecimal), and 'X' (uppercase hexadecimal). +func (z *Int) Scan(s fmt.ScanState, ch rune) error { + s.SkipSpace() // skip leading space characters + base := 0 + switch ch { + case 'b': + base = 2 + case 'o': + base = 8 + case 'd': + base = 10 + case 'x', 'X': + base = 16 + case 's', 'v': + // let scan determine the base + default: + return errors.New("Int.Scan: invalid verb") + } + _, _, err := z.scan(byteReader{s}, base) + return err +} diff --git a/src/math/big/intconv_test.go b/src/math/big/intconv_test.go new file mode 100644 index 0000000000..2deb84b48f --- /dev/null +++ b/src/math/big/intconv_test.go @@ -0,0 +1,342 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package big + +import ( + "bytes" + "fmt" + "testing" +) + +var stringTests = []struct { + in string + out string + base int + val int64 + ok bool +}{ + {in: "", ok: false}, + {in: "a", ok: false}, + {in: "z", ok: false}, + {in: "+", ok: false}, + {in: "-", ok: false}, + {in: "0b", ok: false}, + {in: "0x", ok: false}, + {in: "2", base: 2, ok: false}, + {in: "0b2", base: 0, ok: false}, + {in: "08", ok: false}, + {in: "8", base: 8, ok: false}, + {in: "0xg", base: 0, ok: false}, + {in: "g", base: 16, ok: false}, + {"0", "0", 0, 0, true}, + {"0", "0", 10, 0, true}, + {"0", "0", 16, 0, true}, + {"+0", "0", 0, 0, true}, + {"-0", "0", 0, 0, true}, + {"10", "10", 0, 10, true}, + {"10", "10", 10, 10, true}, + {"10", "10", 16, 16, true}, + {"-10", "-10", 16, -16, true}, + {"+10", "10", 16, 16, true}, + {"0x10", "16", 0, 16, true}, + {in: "0x10", base: 16, ok: false}, + {"-0x10", "-16", 0, -16, true}, + {"+0x10", "16", 0, 16, true}, + {"00", "0", 0, 0, true}, + {"0", "0", 8, 0, true}, + {"07", "7", 0, 7, true}, + {"7", "7", 8, 7, true}, + {"023", "19", 0, 19, true}, + {"23", "23", 8, 19, true}, + {"cafebabe", "cafebabe", 16, 0xcafebabe, true}, + {"0b0", "0", 0, 0, true}, + {"-111", "-111", 2, -7, true}, + {"-0b111", "-7", 0, -7, true}, + {"0b1001010111", "599", 0, 0x257, true}, + {"1001010111", "1001010111", 2, 0x257, true}, +} + +func format(base int) string { + switch base { + case 2: + return "%b" + case 8: + return "%o" + case 16: + return "%x" + } + return "%d" +} + +func TestGetString(t *testing.T) { + z := new(Int) + for i, test := range stringTests { + if !test.ok { + continue + } + z.SetInt64(test.val) + + if test.base == 10 { + s := z.String() + if s != test.out { + t.Errorf("#%da got %s; want %s", i, s, test.out) + } + } + + s := fmt.Sprintf(format(test.base), z) + if s != test.out { + t.Errorf("#%db got %s; want %s", i, s, test.out) + } + } +} + +func TestSetString(t *testing.T) { + tmp := new(Int) + for i, test := range stringTests { + // initialize to a non-zero value so that issues with parsing + // 0 are detected + tmp.SetInt64(1234567890) + n1, ok1 := new(Int).SetString(test.in, test.base) + n2, ok2 := tmp.SetString(test.in, test.base) + expected := NewInt(test.val) + if ok1 != test.ok || ok2 != test.ok { + t.Errorf("#%d (input '%s') ok incorrect (should be %t)", i, test.in, test.ok) + continue + } + if !ok1 { + if n1 != nil { + t.Errorf("#%d (input '%s') n1 != nil", i, test.in) + } + continue + } + if !ok2 { + if n2 != nil { + t.Errorf("#%d (input '%s') n2 != nil", i, test.in) + } + continue + } + + if ok1 && !isNormalized(n1) { + t.Errorf("#%d (input '%s'): %v is not normalized", i, test.in, *n1) + } + if ok2 && !isNormalized(n2) { + t.Errorf("#%d (input '%s'): %v is not normalized", i, test.in, *n2) + } + + if n1.Cmp(expected) != 0 { + t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n1, test.val) + } + if n2.Cmp(expected) != 0 { + t.Errorf("#%d (input '%s') got: %s want: %d", i, test.in, n2, test.val) + } + } +} + +var formatTests = []struct { + input string + format string + output string +}{ + {"", "%x", ""}, + {"", "%#x", ""}, + {"", "%#y", "%!y(big.Int=)"}, + + {"10", "%b", "1010"}, + {"10", "%o", "12"}, + {"10", "%d", "10"}, + {"10", "%v", "10"}, + {"10", "%x", "a"}, + {"10", "%X", "A"}, + {"-10", "%X", "-A"}, + {"10", "%y", "%!y(big.Int=10)"}, + {"-10", "%y", "%!y(big.Int=-10)"}, + + {"10", "%#b", "1010"}, + {"10", "%#o", "012"}, + {"10", "%#d", "10"}, + {"10", "%#v", "10"}, + {"10", "%#x", "0xa"}, + {"10", "%#X", "0XA"}, + {"-10", "%#X", "-0XA"}, + {"10", "%#y", "%!y(big.Int=10)"}, + {"-10", "%#y", "%!y(big.Int=-10)"}, + + {"1234", "%d", "1234"}, + {"1234", "%3d", "1234"}, + {"1234", "%4d", "1234"}, + {"-1234", "%d", "-1234"}, + {"1234", "% 5d", " 1234"}, + {"1234", "%+5d", "+1234"}, + {"1234", "%-5d", "1234 "}, + {"1234", "%x", "4d2"}, + {"1234", "%X", "4D2"}, + {"-1234", "%3x", "-4d2"}, + {"-1234", "%4x", "-4d2"}, + {"-1234", "%5x", " -4d2"}, + {"-1234", "%-5x", "-4d2 "}, + {"1234", "%03d", "1234"}, + {"1234", "%04d", "1234"}, + {"1234", "%05d", "01234"}, + {"1234", "%06d", "001234"}, + {"-1234", "%06d", "-01234"}, + {"1234", "%+06d", "+01234"}, + {"1234", "% 06d", " 01234"}, + {"1234", "%-6d", "1234 "}, + {"1234", "%-06d", "1234 "}, + {"-1234", "%-06d", "-1234 "}, + + {"1234", "%.3d", "1234"}, + {"1234", "%.4d", "1234"}, + {"1234", "%.5d", "01234"}, + {"1234", "%.6d", "001234"}, + {"-1234", "%.3d", "-1234"}, + {"-1234", "%.4d", "-1234"}, + {"-1234", "%.5d", "-01234"}, + {"-1234", "%.6d", "-001234"}, + + {"1234", "%8.3d", " 1234"}, + {"1234", "%8.4d", " 1234"}, + {"1234", "%8.5d", " 01234"}, + {"1234", "%8.6d", " 001234"}, + {"-1234", "%8.3d", " -1234"}, + {"-1234", "%8.4d", " -1234"}, + {"-1234", "%8.5d", " -01234"}, + {"-1234", "%8.6d", " -001234"}, + + {"1234", "%+8.3d", " +1234"}, + {"1234", "%+8.4d", " +1234"}, + {"1234", "%+8.5d", " +01234"}, + {"1234", "%+8.6d", " +001234"}, + {"-1234", "%+8.3d", " -1234"}, + {"-1234", "%+8.4d", " -1234"}, + {"-1234", "%+8.5d", " -01234"}, + {"-1234", "%+8.6d", " -001234"}, + + {"1234", "% 8.3d", " 1234"}, + {"1234", "% 8.4d", " 1234"}, + {"1234", "% 8.5d", " 01234"}, + {"1234", "% 8.6d", " 001234"}, + {"-1234", "% 8.3d", " -1234"}, + {"-1234", "% 8.4d", " -1234"}, + {"-1234", "% 8.5d", " -01234"}, + {"-1234", "% 8.6d", " -001234"}, + + {"1234", "%.3x", "4d2"}, + {"1234", "%.4x", "04d2"}, + {"1234", "%.5x", "004d2"}, + {"1234", "%.6x", "0004d2"}, + {"-1234", "%.3x", "-4d2"}, + {"-1234", "%.4x", "-04d2"}, + {"-1234", "%.5x", "-004d2"}, + {"-1234", "%.6x", "-0004d2"}, + + {"1234", "%8.3x", " 4d2"}, + {"1234", "%8.4x", " 04d2"}, + {"1234", "%8.5x", " 004d2"}, + {"1234", "%8.6x", " 0004d2"}, + {"-1234", "%8.3x", " -4d2"}, + {"-1234", "%8.4x", " -04d2"}, + {"-1234", "%8.5x", " -004d2"}, + {"-1234", "%8.6x", " -0004d2"}, + + {"1234", "%+8.3x", " +4d2"}, + {"1234", "%+8.4x", " +04d2"}, + {"1234", "%+8.5x", " +004d2"}, + {"1234", "%+8.6x", " +0004d2"}, + {"-1234", "%+8.3x", " -4d2"}, + {"-1234", "%+8.4x", " -04d2"}, + {"-1234", "%+8.5x", " -004d2"}, + {"-1234", "%+8.6x", " -0004d2"}, + + {"1234", "% 8.3x", " 4d2"}, + {"1234", "% 8.4x", " 04d2"}, + {"1234", "% 8.5x", " 004d2"}, + {"1234", "% 8.6x", " 0004d2"}, + {"1234", "% 8.7x", " 00004d2"}, + {"1234", "% 8.8x", " 000004d2"}, + {"-1234", "% 8.3x", " -4d2"}, + {"-1234", "% 8.4x", " -04d2"}, + {"-1234", "% 8.5x", " -004d2"}, + {"-1234", "% 8.6x", " -0004d2"}, + {"-1234", "% 8.7x", "-00004d2"}, + {"-1234", "% 8.8x", "-000004d2"}, + + {"1234", "%-8.3d", "1234 "}, + {"1234", "%-8.4d", "1234 "}, + {"1234", "%-8.5d", "01234 "}, + {"1234", "%-8.6d", "001234 "}, + {"1234", "%-8.7d", "0001234 "}, + {"1234", "%-8.8d", "00001234"}, + {"-1234", "%-8.3d", "-1234 "}, + {"-1234", "%-8.4d", "-1234 "}, + {"-1234", "%-8.5d", "-01234 "}, + {"-1234", "%-8.6d", "-001234 "}, + {"-1234", "%-8.7d", "-0001234"}, + {"-1234", "%-8.8d", "-00001234"}, + + {"16777215", "%b", "111111111111111111111111"}, // 2**24 - 1 + + {"0", "%.d", ""}, + {"0", "%.0d", ""}, + {"0", "%3.d", ""}, +} + +func TestFormat(t *testing.T) { + for i, test := range formatTests { + var x *Int + if test.input != "" { + var ok bool + x, ok = new(Int).SetString(test.input, 0) + if !ok { + t.Errorf("#%d failed reading input %s", i, test.input) + } + } + output := fmt.Sprintf(test.format, x) + if output != test.output { + t.Errorf("#%d got %q; want %q, {%q, %q, %q}", i, output, test.output, test.input, test.format, test.output) + } + } +} + +var scanTests = []struct { + input string + format string + output string + remaining int +}{ + {"1010", "%b", "10", 0}, + {"0b1010", "%v", "10", 0}, + {"12", "%o", "10", 0}, + {"012", "%v", "10", 0}, + {"10", "%d", "10", 0}, + {"10", "%v", "10", 0}, + {"a", "%x", "10", 0}, + {"0xa", "%v", "10", 0}, + {"A", "%X", "10", 0}, + {"-A", "%X", "-10", 0}, + {"+0b1011001", "%v", "89", 0}, + {"0xA", "%v", "10", 0}, + {"0 ", "%v", "0", 1}, + {"2+3", "%v", "2", 2}, + {"0XABC 12", "%v", "2748", 3}, +} + +func TestScan(t *testing.T) { + var buf bytes.Buffer + for i, test := range scanTests { + x := new(Int) + buf.Reset() + buf.WriteString(test.input) + if _, err := fmt.Fscanf(&buf, test.format, x); err != nil { + t.Errorf("#%d error: %s", i, err) + } + if x.String() != test.output { + t.Errorf("#%d got %s; want %s", i, x.String(), test.output) + } + if buf.Len() != test.remaining { + t.Errorf("#%d got %d bytes remaining; want %d", i, buf.Len(), test.remaining) + } + } +}