// Copyright 2009 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 fmt_test
import (
"bytes"
. "fmt"
"io"
"math"
"reflect"
"runtime"
"strings"
"testing"
"time"
"unicode"
)
type (
renamedBool bool
renamedInt int
renamedInt8 int8
renamedInt16 int16
renamedInt32 int32
renamedInt64 int64
renamedUint uint
renamedUint8 uint8
renamedUint16 uint16
renamedUint32 uint32
renamedUint64 uint64
renamedUintptr uintptr
renamedString string
renamedBytes []byte
renamedFloat32 float32
renamedFloat64 float64
renamedComplex64 complex64
renamedComplex128 complex128
)
func TestFmtInterface(t *testing.T) {
var i1 interface{}
i1 = "abc"
s := Sprintf("%s", i1)
if s != "abc" {
t.Errorf(`Sprintf("%%s", empty("abc")) = %q want %q`, s, "abc")
}
}
const b32 uint32 = 1<<32 - 1
const b64 uint64 = 1<<64 - 1
var array = [5]int{1, 2, 3, 4, 5}
var iarray = [4]interface{}{1, "hello", 2.5, nil}
var slice = array[:]
var islice = iarray[:]
type A struct {
i int
j uint
s string
x []int
}
type I int
func (i I) String() string { return Sprintf("<%d>", int(i)) }
type B struct {
I I
j int
}
type C struct {
i int
B
}
type F int
func (f F) Format(s State, c rune) {
Fprintf(s, "<%c=F(%d)>", c, int(f))
}
type G int
func (g G) GoString() string {
return Sprintf("GoString(%d)", int(g))
}
type S struct {
F F // a struct field that Formats
G G // a struct field that GoStrings
}
type SI struct {
I interface{}
}
// P is a type with a String method with pointer receiver for testing %p.
type P int
var pValue P
func (p *P) String() string {
return "String(p)"
}
var barray = [5]renamedUint8{1, 2, 3, 4, 5}
var bslice = barray[:]
type byteStringer byte
func (byteStringer) String() string { return "X" }
var byteStringerSlice = []byteStringer{97, 98, 99, 100}
type byteFormatter byte
func (byteFormatter) Format(f State, _ rune) {
Fprint(f, "X")
}
var byteFormatterSlice = []byteFormatter{97, 98, 99, 100}
var b byte
var fmtTests = []struct {
fmt string
val interface{}
out string
}{
{"%d", 12345, "12345"},
{"%v", 12345, "12345"},
{"%t", true, "true"},
// basic string
{"%s", "abc", "abc"},
{"%q", "abc", `"abc"`},
{"%x", "abc", "616263"},
{"%x", "\xff\xf0\x0f\xff", "fff00fff"},
{"%X", "\xff\xf0\x0f\xff", "FFF00FFF"},
{"%x", "xyz", "78797a"},
{"%X", "xyz", "78797A"},
{"% x", "xyz", "78 79 7a"},
{"% X", "xyz", "78 79 7A"},
{"%#x", "xyz", "0x78797a"},
{"%#X", "xyz", "0X78797A"},
{"%# x", "xyz", "0x78 0x79 0x7a"},
{"%# X", "xyz", "0X78 0X79 0X7A"},
// basic bytes
{"%s", []byte("abc"), "abc"},
{"%q", []byte("abc"), `"abc"`},
{"%x", []byte("abc"), "616263"},
{"%x", []byte("\xff\xf0\x0f\xff"), "fff00fff"},
{"%X", []byte("\xff\xf0\x0f\xff"), "FFF00FFF"},
{"%x", []byte("xyz"), "78797a"},
{"%X", []byte("xyz"), "78797A"},
{"% x", []byte("xyz"), "78 79 7a"},
{"% X", []byte("xyz"), "78 79 7A"},
{"%#x", []byte("xyz"), "0x78797a"},
{"%#X", []byte("xyz"), "0X78797A"},
{"%# x", []byte("xyz"), "0x78 0x79 0x7a"},
{"%# X", []byte("xyz"), "0X78 0X79 0X7A"},
// escaped strings
{"%#q", `abc`, "`abc`"},
{"%#q", `"`, "`\"`"},
{"1 %#q", `\n`, "1 `\\n`"},
{"2 %#q", "\n", `2 "\n"`},
{"%q", `"`, `"\""`},
{"%q", "\a\b\f\r\n\t\v", `"\a\b\f\r\n\t\v"`},
{"%q", "abc\xffdef", `"abc\xffdef"`},
{"%q", "\u263a", `"☺"`},
{"%+q", "\u263a", `"\u263a"`},
{"%q", "\U0010ffff", `"\U0010ffff"`},
// escaped characters
{"%q", 'x', `'x'`},
{"%q", 0, `'\x00'`},
{"%q", '\n', `'\n'`},
{"%q", '\u0e00', `'\u0e00'`}, // not a printable rune.
{"%q", '\U000c2345', `'\U000c2345'`}, // not a printable rune.
{"%q", int64(0x7FFFFFFF), `%!q(int64=2147483647)`},
{"%q", uint64(0xFFFFFFFF), `%!q(uint64=4294967295)`},
{"%q", '"', `'"'`},
{"%q", '\'', `'\''`},
{"%q", "\u263a", `"☺"`},
{"%+q", "\u263a", `"\u263a"`},
// width
{"%5s", "abc", " abc"},
{"%2s", "\u263a", " ☺"},
{"%-5s", "abc", "abc "},
{"%-8q", "abc", `"abc" `},
{"%05s", "abc", "00abc"},
{"%08q", "abc", `000"abc"`},
{"%5s", "abcdefghijklmnopqrstuvwxyz", "abcdefghijklmnopqrstuvwxyz"},
{"%.5s", "abcdefghijklmnopqrstuvwxyz", "abcde"},
{"%.5s", "日本語日本語", "日本語日本"},
{"%.5s", []byte("日本語日本語"), "日本語日本"},
{"%.5q", "abcdefghijklmnopqrstuvwxyz", `"abcde"`},
{"%.5x", "abcdefghijklmnopqrstuvwxyz", `6162636465`},
{"%.5q", []byte("abcdefghijklmnopqrstuvwxyz"), `"abcde"`},
{"%.5x", []byte("abcdefghijklmnopqrstuvwxyz"), `6162636465`},
{"%.3q", "日本語日本語", `"日本語"`},
{"%.3q", []byte("日本語日本語"), `"日本語"`},
{"%.1q", "日本語", `"日"`},
{"%.1q", []byte("日本語"), `"日"`},
{"%.1x", "日本語", `e6`},
{"%.1X", []byte("日本語"), `E6`},
{"%10.1q", "日本語日本語", ` "日"`},
{"%3c", '⌘', " ⌘"},
{"%5q", '\u2026', ` '…'`},
{"%10v", nil, " <nil>"},
{"%-10v", nil, "<nil> "},
// integers
{"%d", 12345, "12345"},
{"%d", -12345, "-12345"},
{"%10d", 12345, " 12345"},
{"%10d", -12345, " -12345"},
{"%+10d", 12345, " +12345"},
{"%010d", 12345, "0000012345"},
{"%010d", -12345, "-000012345"},
{"%-10d", 12345, "12345 "},
{"%010.3d", 1, " 001"},
{"%010.3d", -1, " -001"},
{"%+d", 12345, "+12345"},
{"%+d", -12345, "-12345"},
{"%+d", 0, "+0"},
{"% d", 0, " 0"},
{"% d", 12345, " 12345"},
{"%.0d", 0, ""},
{"%.d", 0, ""},
// unicode format
{"%U", 0x1, "U+0001"},
{"%U", uint(0x1), "U+0001"},
{"%.8U", 0x2, "U+00000002"},
{"%U", 0x1234, "U+1234"},
{"%U", 0x12345, "U+12345"},
{"%10.6U", 0xABC, " U+000ABC"},
{"%-10.6U", 0xABC, "U+000ABC "},
{"%U", '\n', `U+000A`},
{"%#U", '\n', `U+000A`},
{"%U", 'x', `U+0078`},
{"%#U", 'x', `U+0078 'x'`},
{"%U", '\u263a', `U+263A`},
{"%#U", '\u263a', `U+263A '☺'`},
// floats
{"%+.3e", 0.0, "+0.000e+00"},
{"%+.3e", 1.0, "+1.000e+00"},
{"%+.3f", -1.0, "-1.000"},
{"%+.3F", -1.0, "-1.000"},
{"%+.3F", float32(-1.0), "-1.000"},
{"%+07.2f", 1.0, "+001.00"},
{"%+07.2f", -1.0, "-001.00"},
{"%+10.2f", +1.0, " +1.00"},
{"%+10.2f", -1.0, " -1.00"},
{"% .3E", -1.0, "-1.000E+00"},
{"% .3e", 1.0, " 1.000e+00"},
{"%+.3g", 0.0, "+0"},
{"%+.3g", 1.0, "+1"},
{"%+.3g", -1.0, "-1"},
{"% .3g", -1.0, "-1"},
{"% .3g", 1.0, " 1"},
{"%b", float32(1.0), "8388608p-23"},
{"%b", 1.0, "4503599627370496p-52"},
// complex values
{"%+.3e", 0i, "(+0.000e+00+0.000e+00i)"},
{"%+.3f", 0i, "(+0.000+0.000i)"},
{"%+.3g", 0i, "(+0+0i)"},
{"%+.3e", 1 + 2i, "(+1.000e+00+2.000e+00i)"},
{"%+.3f", 1 + 2i, "(+1.000+2.000i)"},
{"%+.3g", 1 + 2i, "(+1+2i)"},
{"%.3e", 0i, "(0.000e+00+0.000e+00i)"},
{"%.3f", 0i, "(0.000+0.000i)"},
{"%.3F", 0i, "(0.000+0.000i)"},
{"%.3F", complex64(0i), "(0.000+0.000i)"},
{"%.3g", 0i, "(0+0i)"},
{"%.3e", 1 + 2i, "(1.000e+00+2.000e+00i)"},
{"%.3f", 1 + 2i, "(1.000+2.000i)"},
{"%.3g", 1 + 2i, "(1+2i)"},
{"%.3e", -1 - 2i, "(-1.000e+00-2.000e+00i)"},
{"%.3f", -1 - 2i, "(-1.000-2.000i)"},
{"%.3g", -1 - 2i, "(-1-2i)"},
{"% .3E", -1 - 2i, "(-1.000E+00-2.000E+00i)"},
{"%+.3g", complex64(1 + 2i), "(+1+2i)"},
{"%+.3g", complex128(1 + 2i), "(+1+2i)"},
{"%b", complex64(1 + 2i), "(8388608p-23+8388608p-22i)"},
{"%b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
// erroneous formats
{"", 2, "%!(EXTRA int=2)"},
{"%d", "hello", "%!d(string=hello)"},
// old test/fmt_test.go
{"%d", 1234, "1234"},
{"%d", -1234, "-1234"},
{"%d", uint(1234), "1234"},
{"%d", uint32(b32), "4294967295"},
{"%d", uint64(b64), "18446744073709551615"},
{"%o", 01234, "1234"},
{"%#o", 01234, "01234"},
{"%o", uint32(b32), "37777777777"},
{"%o", uint64(b64), "1777777777777777777777"},
{"%x", 0x1234abcd, "1234abcd"},
{"%#x", 0x1234abcd, "0x1234abcd"},
{"%x", b32 - 0x1234567, "fedcba98"},
{"%X", 0x1234abcd, "1234ABCD"},
{"%X", b32 - 0x1234567, "FEDCBA98"},
{"%#X", 0, "0X0"},
{"%x", b64, "ffffffffffffffff"},
{"%b", 7, "111"},
{"%b", b64, "1111111111111111111111111111111111111111111111111111111111111111"},
{"%b", -6, "-110"},
{"%e", 1.0, "1.000000e+00"},
{"%e", 1234.5678e3, "1.234568e+06"},
{"%e", 1234.5678e-8, "1.234568e-05"},
{"%e", -7.0, "-7.000000e+00"},
{"%e", -1e-9, "-1.000000e-09"},
{"%f", 1234.5678e3, "1234567.800000"},
{"%f", 1234.5678e-8, "0.000012"},
{"%f", -7.0, "-7.000000"},
{"%f", -1e-9, "-0.000000"},
{"%g", 1234.5678e3, "1.2345678e+06"},
{"%g", float32(1234.5678e3), "1.2345678e+06"},
{"%g", 1234.5678e-8, "1.2345678e-05"},
{"%g", -7.0, "-7"},
{"%g", -1e-9, "-1e-09"},
{"%g", float32(-1e-9), "-1e-09"},
{"%E", 1.0, "1.000000E+00"},
{"%E", 1234.5678e3, "1.234568E+06"},
{"%E", 1234.5678e-8, "1.234568E-05"},
{"%E", -7.0, "-7.000000E+00"},
{"%E", -1e-9, "-1.000000E-09"},
{"%G", 1234.5678e3, "1.2345678E+06"},
{"%G", float32(1234.5678e3), "1.2345678E+06"},
{"%G", 1234.5678e-8, "1.2345678E-05"},
{"%G", -7.0, "-7"},
{"%G", -1e-9, "-1E-09"},
{"%G", float32(-1e-9), "-1E-09"},
{"%c", 'x', "x"},
{"%c", 0xe4, "ä"},
{"%c", 0x672c, "本"},
{"%c", '日', "日"},
{"%20.8d", 1234, " 00001234"},
{"%20.8d", -1234, " -00001234"},
{"%20d", 1234, " 1234"},
{"%-20.8d", 1234, "00001234 "},
{"%-20.8d", -1234, "-00001234 "},
{"%-#20.8x", 0x1234abc, "0x01234abc "},
{"%-#20.8X", 0x1234abc, "0X01234ABC "},
{"%-#20.8o", 01234, "00001234 "},
{"%.20b", 7, "00000000000000000111"},
{"%20.5s", "qwertyuiop", " qwert"},
{"%.5s", "qwertyuiop", "qwert"},
{"%-20.5s", "qwertyuiop", "qwert "},
{"%20c", 'x', " x"},
{"%-20c", 'x', "x "},
{"%20.6e", 1.2345e3, " 1.234500e+03"},
{"%20.6e", 1.2345e-3, " 1.234500e-03"},
{"%20e", 1.2345e3, " 1.234500e+03"},
{"%20e", 1.2345e-3, " 1.234500e-03"},
{"%20.8e", 1.2345e3, " 1.23450000e+03"},
{"%20f", 1.23456789e3, " 1234.567890"},
{"%20f", 1.23456789e-3, " 0.001235"},
{"%20f", 12345678901.23456789, " 12345678901.234568"},
{"%-20f", 1.23456789e3, "1234.567890 "},
{"%20.8f", 1.23456789e3, " 1234.56789000"},
{"%20.8f", 1.23456789e-3, " 0.00123457"},
{"%g", 1.23456789e3, "1234.56789"},
{"%g", 1.23456789e-3, "0.00123456789"},
{"%g", 1.23456789e20, "1.23456789e+20"},
{"%20e", math.Inf(1), " +Inf"},
{"%-20f", math.Inf(-1), "-Inf "},
{"%20g", math.NaN(), " NaN"},
// arrays
{"%v", array, "[1 2 3 4 5]"},
{"%v", iarray, "[1 hello 2.5 <nil>]"},
{"%v", barray, "[1 2 3 4 5]"},
{"%v", &array, "&[1 2 3 4 5]"},
{"%v", &iarray, "&[1 hello 2.5 <nil>]"},
{"%v", &barray, "&[1 2 3 4 5]"},
// slices
{"%v", slice, "[1 2 3 4 5]"},
{"%v", islice, "[1 hello 2.5 <nil>]"},
{"%v", bslice, "[1 2 3 4 5]"},
{"%v", &slice, "&[1 2 3 4 5]"},
{"%v", &islice, "&[1 hello 2.5 <nil>]"},
{"%v", &bslice, "&[1 2 3 4 5]"},
{"%v", []byte{1}, "[1]"},
{"%v", []byte{}, "[]"},
// complexes with %v
{"%v", 1 + 2i, "(1+2i)"},
{"%v", complex64(1 + 2i), "(1+2i)"},
{"%v", complex128(1 + 2i), "(1+2i)"},
// structs
{"%v", A{1, 2, "a", []int{1, 2}}, `{1 2 a [1 2]}`},
{"%+v", A{1, 2, "a", []int{1, 2}}, `{i:1 j:2 s:a x:[1 2]}`},
// +v on structs with Stringable items
{"%+v", B{1, 2}, `{I:<1> j:2}`},
{"%+v", C{1, B{2, 3}}, `{i:1 B:{I:<2> j:3}}`},
// other formats on Stringable items
{"%s", I(23), `<23>`},
{"%q", I(23), `"<23>"`},
{"%x", I(23), `3c32333e`},
{"%#x", I(23), `0x3c32333e`},
{"%# x", I(23), `0x3c 0x32 0x33 0x3e`},
{"%d", I(23), `23`}, // Stringer applies only to string formats.
// go syntax
{"%#v", A{1, 2, "a", []int{1, 2}}, `fmt_test.A{i:1, j:0x2, s:"a", x:[]int{1, 2}}`},
{"%#v", &b, "(*uint8)(0xPTR)"},
{"%#v", TestFmtInterface, "(func(*testing.T))(0xPTR)"},
{"%#v", make(chan int), "(chan int)(0xPTR)"},
{"%#v", uint64(1<<64 - 1), "0xffffffffffffffff"},
{"%#v", 1000000000, "1000000000"},
{"%#v", map[string]int{"a": 1}, `map[string]int{"a":1}`},
{"%#v", map[string]B{"a": {1, 2}}, `map[string]fmt_test.B{"a":fmt_test.B{I:1, j:2}}`},
{"%#v", []string{"a", "b"}, `[]string{"a", "b"}`},
{"%#v", SI{}, `fmt_test.SI{I:interface {}(nil)}`},
{"%#v", []int(nil), `[]int(nil)`},
{"%#v", []int{}, `[]int{}`},
{"%#v", array, `[5]int{1, 2, 3, 4, 5}`},
{"%#v", &array, `&[5]int{1, 2, 3, 4, 5}`},
{"%#v", iarray, `[4]interface {}{1, "hello", 2.5, interface {}(nil)}`},
{"%#v", &iarray, `&[4]interface {}{1, "hello", 2.5, interface {}(nil)}`},
{"%#v", map[int]byte(nil), `map[int]uint8(nil)`},
{"%#v", map[int]byte{}, `map[int]uint8{}`},
{"%#v", "foo", `"foo"`},
{"%#v", barray, `[5]fmt_test.renamedUint8{0x1, 0x2, 0x3, 0x4, 0x5}`},
{"%#v", bslice, `[]fmt_test.renamedUint8{0x1, 0x2, 0x3, 0x4, 0x5}`},
{"%#v", []byte(nil), "[]byte(nil)"},
{"%#v", []int32(nil), "[]int32(nil)"},
// slices with other formats
{"%#x", []int{1, 2, 15}, `[0x1 0x2 0xf]`},
{"%x", []int{1, 2, 15}, `[1 2 f]`},
{"%d", []int{1, 2, 15}, `[1 2 15]`},
{"%d", []byte{1, 2, 15}, `[1 2 15]`},
{"%q", []string{"a", "b"}, `["a" "b"]`},
{"% 02x", []byte{1}, "01"},
{"% 02x", []byte{1, 2, 3}, "01 02 03"},
// Padding with byte slices.
{"%x", []byte{}, ""},
{"%02x", []byte{}, "00"},
{"% 02x", []byte{}, "00"},
{"%08x", []byte{0xab}, "000000ab"},
{"% 08x", []byte{0xab}, "000000ab"},
{"%08x", []byte{0xab, 0xcd}, "0000abcd"},
{"% 08x", []byte{0xab, 0xcd}, "000ab cd"},
{"%8x", []byte{0xab}, " ab"},
{"% 8x", []byte{0xab}, " ab"},
{"%8x", []byte{0xab, 0xcd}, " abcd"},
{"% 8x", []byte{0xab, 0xcd}, " ab cd"},
// Same for strings
{"%x", "", ""},
{"%02x", "", "00"},
{"% 02x", "", "00"},
{"%08x", "\xab", "000000ab"},
{"% 08x", "\xab", "000000ab"},
{"%08x", "\xab\xcd", "0000abcd"},
{"% 08x", "\xab\xcd", "000ab cd"},
{"%8x", "\xab", " ab"},
{"% 8x", "\xab", " ab"},
{"%8x", "\xab\xcd", " abcd"},
{"% 8x", "\xab\xcd", " ab cd"},
// renamings
{"%v", renamedBool(true), "true"},
{"%d", renamedBool(true), "%!d(fmt_test.renamedBool=true)"},
{"%o", renamedInt(8), "10"},
{"%d", renamedInt8(-9), "-9"},
{"%v", renamedInt16(10), "10"},
{"%v", renamedInt32(-11), "-11"},
{"%X", renamedInt64(255), "FF"},
{"%v", renamedUint(13), "13"},
{"%o", renamedUint8(14), "16"},
{"%X", renamedUint16(15), "F"},
{"%d", renamedUint32(16), "16"},
{"%X", renamedUint64(17), "11"},
{"%o", renamedUintptr(18), "22"},
{"%x", renamedString("thing"), "7468696e67"},
{"%d", renamedBytes([]byte{1, 2, 15}), `[1 2 15]`},
{"%q", renamedBytes([]byte("hello")), `"hello"`},
{"%x", []renamedUint8{'a', 'b', 'c'}, "616263"},
{"%s", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, "hello"},
{"%q", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, `"hello"`},
{"%v", renamedFloat32(22), "22"},
{"%v", renamedFloat64(33), "33"},
{"%v", renamedComplex64(3 + 4i), "(3+4i)"},
{"%v", renamedComplex128(4 - 3i), "(4-3i)"},
// Formatter
{"%x", F(1), "<x=F(1)>"},
{"%x", G(2), "2"},
{"%+v", S{F(4), G(5)}, "{F:<v=F(4)> G:5}"},
// GoStringer
{"%#v", G(6), "GoString(6)"},
{"%#v", S{F(7), G(8)}, "fmt_test.S{F:<v=F(7)>, G:GoString(8)}"},
// %T
{"%T", (4 - 3i), "complex128"},
{"%T", renamedComplex128(4 - 3i), "fmt_test.renamedComplex128"},
{"%T", intVal, "int"},
{"%6T", &intVal, " *int"},
{"%10T", nil, " <nil>"},
{"%-10T", nil, "<nil> "},
// %p
{"p0=%p", new(int), "p0=0xPTR"},
{"p1=%s", &pValue, "p1=String(p)"}, // String method...
{"p2=%p", &pValue, "p2=0xPTR"}, // ... not called with %p
{"p3=%p", (*int)(nil), "p3=0x0"},
{"p4=%#p", new(int), "p4=PTR"},
// %p on non-pointers
{"%p", make(chan int), "0xPTR"},
{"%p", make(map[int]int), "0xPTR"},
{"%p", make([]int, 1), "0xPTR"},
{"%p", 27, "%!p(int=27)"}, // not a pointer at all
// %q on pointers
{"%q", (*int)(nil), "%!q(*int=<nil>)"},
{"%q", new(int), "%!q(*int=0xPTR)"},
// %v on pointers formats 0 as <nil>
{"%v", (*int)(nil), "<nil>"},
{"%v", new(int), "0xPTR"},
// %d etc. pointers use specified base.
{"%d", new(int), "PTR_d"},
{"%o", new(int), "PTR_o"},
{"%x", new(int), "PTR_x"},
// %d on Stringer should give integer if possible
{"%s", time.Time{}.Month(), "January"},
{"%d", time.Time{}.Month(), "1"},
// erroneous things
{"%s %", "hello", "hello %!(NOVERB)"},
{"%s %.2", "hello", "hello %!(NOVERB)"},
{"%d", "hello", "%!d(string=hello)"},
{"no args", "hello", "no args%!(EXTRA string=hello)"},
{"%s", nil, "%!s(<nil>)"},
{"%T", nil, "<nil>"},
{"%-1", 100, "%!(NOVERB)%!(EXTRA int=100)"},
{"%017091901790959340919092959340919017929593813360", 0, "%!(NOVERB)%!(EXTRA int=0)"},
{"%184467440737095516170v", 0, "%!(NOVERB)%!(EXTRA int=0)"},
// The "<nil>" show up because maps are printed by
// first obtaining a list of keys and then looking up
// each key. Since NaNs can be map keys but cannot
// be fetched directly, the lookup fails and returns a
// zero reflect.Value, which formats as <nil>.
// This test is just to check that it shows the two NaNs at all.
{"%v", map[float64]int{math.NaN(): 1, math.NaN(): 2}, "map[NaN:<nil> NaN:<nil>]"},
// Used to crash because nByte didn't allow for a sign.
{"%b", int64(-1 << 63), zeroFill("-1", 63, "")},
// Used to panic.
{"%0100d", 1, zeroFill("", 100, "1")},
{"%0100d", -1, zeroFill("-", 99, "1")},
{"%0.100f", 1.0, zeroFill("1.", 100, "")},
{"%0.100f", -1.0, zeroFill("-1.", 100, "")},
// Used to panic: integer function didn't look at f.prec, f.unicode, f.width or sign.
{"%#.80x", 42, "0x0000000000000000000000000000000000000000000000000000000000000000000000000000002a"},
{"%.80U", 42, "U+0000000000000000000000000000000000000000000000000000000000000000000000000000002A"},
{"%#.80U", '日', "U+000000000000000000000000000000000000000000000000000000000000000000000000000065E5 '日'"},
{"%.65d", -44, "-00000000000000000000000000000000000000000000000000000000000000044"},
{"%+.65d", 44, "+00000000000000000000000000000000000000000000000000000000000000044"},
{"% .65d", 44, " 00000000000000000000000000000000000000000000000000000000000000044"},
{"% +.65d", 44, "+00000000000000000000000000000000000000000000000000000000000000044"},
// Comparison of padding rules with C printf.
/*
C program:
#include <stdio.h>
char *format[] = {
"[%.2f]",
"[% .2f]",
"[%+.2f]",
"[%7.2f]",
"[% 7.2f]",
"[%+7.2f]",
"[%07.2f]",
"[% 07.2f]",
"[%+07.2f]",
};
int main(void) {
int i;
for(i = 0; i < 9; i++) {
printf("%s: ", format[i]);
printf(format[i], 1.0);
printf(" ");
printf(format[i], -1.0);
printf("\n");
}
}
Output:
[%.2f]: [1.00] [-1.00]
[% .2f]: [ 1.00] [-1.00]
[%+.2f]: [+1.00] [-1.00]
[%7.2f]: [ 1.00] [ -1.00]
[% 7.2f]: [ 1.00] [ -1.00]
[%+7.2f]: [ +1.00] [ -1.00]
[%07.2f]: [0001.00] [-001.00]
[% 07.2f]: [ 001.00] [-001.00]
[%+07.2f]: [+001.00] [-001.00]
*/
{"%.2f", 1.0, "1.00"},
{"%.2f", -1.0, "-1.00"},
{"% .2f", 1.0, " 1.00"},
{"% .2f", -1.0, "-1.00"},
{"%+.2f", 1.0, "+1.00"},
{"%+.2f", -1.0, "-1.00"},
{"%7.2f", 1.0, " 1.00"},
{"%7.2f", -1.0, " -1.00"},
{"% 7.2f", 1.0, " 1.00"},
{"% 7.2f", -1.0, " -1.00"},
{"%+7.2f", 1.0, " +1.00"},
{"%+7.2f", -1.0, " -1.00"},
{"%07.2f", 1.0, "0001.00"},
{"%07.2f", -1.0, "-001.00"},
{"% 07.2f", 1.0, " 001.00"},
{"% 07.2f", -1.0, "-001.00"},
{"%+07.2f", 1.0, "+001.00"},
{"%+07.2f", -1.0, "-001.00"},
// Complex numbers: exhaustively tested in TestComplexFormatting.
{"%7.2f", 1 + 2i, "( 1.00 +2.00i)"},
{"%+07.2f", -1 - 2i, "(-001.00-002.00i)"},
// Zero padding does not apply to infinities.
{"%020f", math.Inf(-1), " -Inf"},
{"%020f", math.Inf(+1), " +Inf"},
{"% 020f", math.Inf(-1), " -Inf"},
{"% 020f", math.Inf(+1), " Inf"},
{"%+020f", math.Inf(-1), " -Inf"},
{"%+020f", math.Inf(+1), " +Inf"},
{"%20f", -1.0, " -1.000000"},
// Make sure we can handle very large widths.
{"%0100f", -1.0, zeroFill("-", 99, "1.000000")},
// Complex fmt used to leave the plus flag set for future entries in the array
// causing +2+0i and +3+0i instead of 2+0i and 3+0i.
{"%v", []complex64{1, 2, 3}, "[(1+0i) (2+0i) (3+0i)]"},
{"%v", []complex128{1, 2, 3}, "[(1+0i) (2+0i) (3+0i)]"},
// Incomplete format specification caused crash.
{"%.", 3, "%!.(int=3)"},
// Used to panic with out-of-bounds for very large numeric representations.
// nByte is set to handle one bit per uint64 in %b format, with a negative number.
// See issue 6777.
{"%#064x", 1, zeroFill("0x", 64, "1")},
{"%#064x", -1, zeroFill("-0x", 63, "1")},
{"%#064b", 1, zeroFill("", 64, "1")},
{"%#064b", -1, zeroFill("-", 63, "1")},
{"%#064o", 1, zeroFill("", 64, "1")},
{"%#064o", -1, zeroFill("-", 63, "1")},
{"%#064d", 1, zeroFill("", 64, "1")},
{"%#064d", -1, zeroFill("-", 63, "1")},
// Test that we handle the crossover above the size of uint64
{"%#072x", 1, zeroFill("0x", 72, "1")},
{"%#072x", -1, zeroFill("-0x", 71, "1")},
{"%#072b", 1, zeroFill("", 72, "1")},
{"%#072b", -1, zeroFill("-", 71, "1")},
{"%#072o", 1, zeroFill("", 72, "1")},
{"%#072o", -1, zeroFill("-", 71, "1")},
{"%#072d", 1, zeroFill("", 72, "1")},
{"%#072d", -1, zeroFill("-", 71, "1")},
// Padding for complex numbers. Has been bad, then fixed, then bad again.
{"%+10.2f", +104.66 + 440.51i, "( +104.66 +440.51i)"},
{"%+10.2f", -104.66 + 440.51i, "( -104.66 +440.51i)"},
{"%+10.2f", +104.66 - 440.51i, "( +104.66 -440.51i)"},
{"%+10.2f", -104.66 - 440.51i, "( -104.66 -440.51i)"},
{"%+010.2f", +104.66 + 440.51i, "(+000104.66+000440.51i)"},
{"%+010.2f", -104.66 + 440.51i, "(-000104.66+000440.51i)"},
{"%+010.2f", +104.66 - 440.51i, "(+000104.66-000440.51i)"},
{"%+010.2f", -104.66 - 440.51i, "(-000104.66-000440.51i)"},
// []T where type T is a byte with a Stringer method.
{"%v", byteStringerSlice, "[X X X X]"},
{"%s", byteStringerSlice, "abcd"},
{"%q", byteStringerSlice, "\"abcd\""},
{"%x", byteStringerSlice, "61626364"},
{"%#v", byteStringerSlice, "[]fmt_test.byteStringer{0x61, 0x62, 0x63, 0x64}"},
// And the same for Formatter.
{"%v", byteFormatterSlice, "[X X X X]"},
{"%s", byteFormatterSlice, "abcd"},
{"%q", byteFormatterSlice, "\"abcd\""},
{"%x", byteFormatterSlice, "61626364"},
// This next case seems wrong, but the docs say the Formatter wins here.
{"%#v", byteFormatterSlice, "[]fmt_test.byteFormatter{X, X, X, X}"},
// reflect.Value handled specially in Go 1.5, making it possible to
// see inside non-exported fields (which cannot be accessed with Interface()).
// Issue 8965.
{"%v", reflect.ValueOf(A{}).Field(0).String(), "<int Value>"}, // Equivalent to the old way.
{"%v", reflect.ValueOf(A{}).Field(0), "0"}, // Sees inside the field.
// verbs apply to the extracted value too.
{"%s", reflect.ValueOf("hello"), "hello"},
{"%q", reflect.ValueOf("hello"), `"hello"`},
{"%#04x", reflect.ValueOf(256), "0x0100"},
// invalid reflect.Value doesn't crash.
{"%v", reflect.Value{}, "<invalid reflect.Value>"},
}
// zeroFill generates zero-filled strings of the specified width. The length
// of the suffix (but not the prefix) is compensated for in the width calculation.
func zeroFill(prefix string, width int, suffix string) string {
return prefix + strings.Repeat("0", width-len(suffix)) + suffix
}
func TestSprintf(t *testing.T) {
for _, tt := range fmtTests {
s := Sprintf(tt.fmt, tt.val)
if i := strings.Index(tt.out, "PTR"); i >= 0 {
pattern := "PTR"
chars := "0123456789abcdefABCDEF"
switch {
case strings.HasPrefix(tt.out[i:], "PTR_d"):
pattern = "PTR_d"
chars = chars[:10]
case strings.HasPrefix(tt.out[i:], "PTR_o"):
pattern = "PTR_o"
chars = chars[:8]
case strings.HasPrefix(tt.out[i:], "PTR_x"):
pattern = "PTR_x"
}
j := i
for ; j < len(s); j++ {
c := s[j]
if !strings.ContainsRune(chars, rune(c)) {
break
}
}
s = s[0:i] + pattern + s[j:]
}
if s != tt.out {
if _, ok := tt.val.(string); ok {
// Don't requote the already-quoted strings.
// It's too confusing to read the errors.
t.Errorf("Sprintf(%q, %q) = <%s> want <%s>", tt.fmt, tt.val, s, tt.out)
} else {
t.Errorf("Sprintf(%q, %v) = %q want %q", tt.fmt, tt.val, s, tt.out)
}
}
}
}
// TestComplexFormatting checks that a complex always formats to the same
// thing as if done by hand with two singleton prints.
func TestComplexFormatting(t *testing.T) {
var yesNo = []bool{true, false}
var values = []float64{1, 0, -1, math.Inf(1), math.Inf(-1), math.NaN()}
for _, plus := range yesNo {
for _, zero := range yesNo {
for _, space := range yesNo {
for _, char := range "fFeEgG" {
realFmt := "%"
if zero {
realFmt += "0"
}
if space {
realFmt += " "
}
if plus {
realFmt += "+"
}
realFmt += "10.2"
realFmt += string(char)
// Imaginary part always has a sign, so force + and ignore space.
imagFmt := "%"
if zero {
imagFmt += "0"
}
imagFmt += "+"
imagFmt += "10.2"
imagFmt += string(char)
for _, realValue := range values {
for _, imagValue := range values {
one := Sprintf(realFmt, complex(realValue, imagValue))
two := Sprintf("("+realFmt+imagFmt+"i)", realValue, imagValue)
if one != two {
t.Error(f, one, two)
}
}
}
}
}
}
}
}
type SE []interface{} // slice of empty; notational compactness.
var reorderTests = []struct {
fmt string
val SE
out string
}{
{"%[1]d", SE{1}, "1"},
{"%[2]d", SE{2, 1}, "1"},
{"%[2]d %[1]d", SE{1, 2}, "2 1"},
{"%[2]*[1]d", SE{2, 5}, " 2"},
{"%6.2f", SE{12.0}, " 12.00"}, // Explicit version of next line.
{"%[3]*.[2]*[1]f", SE{12.0, 2, 6}, " 12.00"},
{"%[1]*.[2]*[3]f", SE{6, 2, 12.0}, " 12.00"},
{"%10f", SE{12.0}, " 12.000000"},
{"%[1]*[3]f", SE{10, 99, 12.0}, " 12.000000"},
{"%.6f", SE{12.0}, "12.000000"}, // Explicit version of next line.
{"%.[1]*[3]f", SE{6, 99, 12.0}, "12.000000"},
{"%6.f", SE{12.0}, " 12"}, // // Explicit version of next line; empty precision means zero.
{"%[1]*.[3]f", SE{6, 3, 12.0}, " 12"},
// An actual use! Print the same arguments twice.
{"%d %d %d %#[1]o %#o %#o", SE{11, 12, 13}, "11 12 13 013 014 015"},
// Erroneous cases.
{"%[d", SE{2, 1}, "%!d(BADINDEX)"},
{"%]d", SE{2, 1}, "%!](int=2)d%!(EXTRA int=1)"},
{"%[]d", SE{2, 1}, "%!d(BADINDEX)"},
{"%[-3]d", SE{2, 1}, "%!d(BADINDEX)"},
{"%[99]d", SE{2, 1}, "%!d(BADINDEX)"},
{"%[3]", SE{2, 1}, "%!(NOVERB)"},
{"%[1].2d", SE{5, 6}, "%!d(BADINDEX)"},
{"%[1]2d", SE{2, 1}, "%!d(BADINDEX)"},
{"%3.[2]d", SE{7}, "%!d(BADINDEX)"},
{"%.[2]d", SE{7}, "%!d(BADINDEX)"},
{"%d %d %d %#[1]o %#o %#o %#o", SE{11, 12, 13}, "11 12 13 013 014 015 %!o(MISSING)"},
{"%[5]d %[2]d %d", SE{1, 2, 3}, "%!d(BADINDEX) 2 3"},
{"%d %[3]d %d", SE{1, 2}, "1 %!d(BADINDEX) 2"}, // Erroneous index does not affect sequence.
{"%.[]", SE{}, "%!](BADINDEX)"}, // Issue 10675
{"%.-3d", SE{42}, "%!-(int=42)3d"}, // TODO: Should this set return better error messages?
{"%2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
{"%-2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
{"%.2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
}
func TestReorder(t *testing.T) {
for _, tt := range reorderTests {
s := Sprintf(tt.fmt, tt.val...)
if s != tt.out {
t.Errorf("Sprintf(%q, %v) = <%s> want <%s>", tt.fmt, tt.val, s, tt.out)
} else {
}
}
}
func BenchmarkSprintfEmpty(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("")
}
})
}
func BenchmarkSprintfString(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("%s", "hello")
}
})
}
func BenchmarkSprintfInt(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("%d", 5)
}
})
}
func BenchmarkSprintfIntInt(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("%d %d", 5, 6)
}
})
}
func BenchmarkSprintfPrefixedInt(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("This is some meaningless prefix text that needs to be scanned %d", 6)
}
})
}
func BenchmarkSprintfFloat(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
Sprintf("%g", 5.23184)
}
})
}
func BenchmarkManyArgs(b *testing.B) {
b.RunParallel(func(pb *testing.PB) {
var buf bytes.Buffer
for pb.Next() {
buf.Reset()
Fprintf(&buf, "%2d/%2d/%2d %d:%d:%d %s %s\n", 3, 4, 5, 11, 12, 13, "hello", "world")
}
})
}
func BenchmarkFprintInt(b *testing.B) {
var buf bytes.Buffer
for i := 0; i < b.N; i++ {
buf.Reset()
Fprint(&buf, 123456)
}
}
func BenchmarkFprintfBytes(b *testing.B) {
data := []byte(string("0123456789"))
var buf bytes.Buffer
for i := 0; i < b.N; i++ {
buf.Reset()
Fprintf(&buf, "%s", data)
}
}
func BenchmarkFprintIntNoAlloc(b *testing.B) {
var x interface{} = 123456
var buf bytes.Buffer
for i := 0; i < b.N; i++ {
buf.Reset()
Fprint(&buf, x)
}
}
var mallocBuf bytes.Buffer
var mallocPointer *int // A pointer so we know the interface value won't allocate.
var mallocTest = []struct {
count int
desc string
fn func()
}{
{0, `Sprintf("")`, func() { Sprintf("") }},
{1, `Sprintf("xxx")`, func() { Sprintf("xxx") }},
{2, `Sprintf("%x")`, func() { Sprintf("%x", 7) }},
{2, `Sprintf("%s")`, func() { Sprintf("%s", "hello") }},
{3, `Sprintf("%x %x")`, func() { Sprintf("%x %x", 7, 112) }},
{2, `Sprintf("%g")`, func() { Sprintf("%g", float32(3.14159)) }}, // TODO: Can this be 1?
{1, `Fprintf(buf, "%s")`, func() { mallocBuf.Reset(); Fprintf(&mallocBuf, "%s", "hello") }},
// If the interface value doesn't need to allocate, amortized allocation overhead should be zero.
{0, `Fprintf(buf, "%x %x %x")`, func() {
mallocBuf.Reset()
Fprintf(&mallocBuf, "%x %x %x", mallocPointer, mallocPointer, mallocPointer)
}},
}
var _ bytes.Buffer
func TestCountMallocs(t *testing.T) {
switch {
case testing.Short():
t.Skip("skipping malloc count in short mode")
case runtime.GOMAXPROCS(0) > 1:
t.Skip("skipping; GOMAXPROCS>1")
case raceenabled:
t.Skip("skipping malloc count under race detector")
}
for _, mt := range mallocTest {
mallocs := testing.AllocsPerRun(100, mt.fn)
if got, max := mallocs, float64(mt.count); got > max {
t.Errorf("%s: got %v allocs, want <=%v", mt.desc, got, max)
}
}
}
type flagPrinter struct{}
func (flagPrinter) Format(f State, c rune) {
s := "%"
for i := 0; i < 128; i++ {
if f.Flag(i) {
s += string(i)
}
}
if w, ok := f.Width(); ok {
s += Sprintf("%d", w)
}
if p, ok := f.Precision(); ok {
s += Sprintf(".%d", p)
}
s += string(c)
io.WriteString(f, "["+s+"]")
}
var flagtests = []struct {
in string
out string
}{
{"%a", "[%a]"},
{"%-a", "[%-a]"},
{"%+a", "[%+a]"},
{"%#a", "[%#a]"},
{"% a", "[% a]"},
{"%0a", "[%0a]"},
{"%1.2a", "[%1.2a]"},
{"%-1.2a", "[%-1.2a]"},
{"%+1.2a", "[%+1.2a]"},
{"%-+1.2a", "[%+-1.2a]"},
{"%-+1.2abc", "[%+-1.2a]bc"},
{"%-1.2abc", "[%-1.2a]bc"},
}
func TestFlagParser(t *testing.T) {
var flagprinter flagPrinter
for _, tt := range flagtests {
s := Sprintf(tt.in, &flagprinter)
if s != tt.out {
t.Errorf("Sprintf(%q, &flagprinter) => %q, want %q", tt.in, s, tt.out)
}
}
}
func TestStructPrinter(t *testing.T) {
type T struct {
a string
b string
c int
}
var s T
s.a = "abc"
s.b = "def"
s.c = 123
var tests = []struct {
fmt string
out string
}{
{"%v", "{abc def 123}"},
{"%+v", "{a:abc b:def c:123}"},
{"%#v", `fmt_test.T{a:"abc", b:"def", c:123}`},
}
for _, tt := range tests {
out := Sprintf(tt.fmt, s)
if out != tt.out {
t.Errorf("Sprintf(%q, s) = %#q, want %#q", tt.fmt, out, tt.out)
}
// The same but with a pointer.
out = Sprintf(tt.fmt, &s)
if out != "&"+tt.out {
t.Errorf("Sprintf(%q, &s) = %#q, want %#q", tt.fmt, out, "&"+tt.out)
}
}
}
func TestSlicePrinter(t *testing.T) {
slice := []int{}
s := Sprint(slice)
if s != "[]" {
t.Errorf("empty slice printed as %q not %q", s, "[]")
}
slice = []int{1, 2, 3}
s = Sprint(slice)
if s != "[1 2 3]" {
t.Errorf("slice: got %q expected %q", s, "[1 2 3]")
}
s = Sprint(&slice)
if s != "&[1 2 3]" {
t.Errorf("&slice: got %q expected %q", s, "&[1 2 3]")
}
}
// presentInMap checks map printing using substrings so we don't depend on the
// print order.
func presentInMap(s string, a []string, t *testing.T) {
for i := 0; i < len(a); i++ {
loc := strings.Index(s, a[i])
if loc < 0 {
t.Errorf("map print: expected to find %q in %q", a[i], s)
}
// make sure the match ends here
loc += len(a[i])
if loc >= len(s) || (s[loc] != ' ' && s[loc] != ']') {
t.Errorf("map print: %q not properly terminated in %q", a[i], s)
}
}
}
func TestMapPrinter(t *testing.T) {
m0 := make(map[int]string)
s := Sprint(m0)
if s != "map[]" {
t.Errorf("empty map printed as %q not %q", s, "map[]")
}
m1 := map[int]string{1: "one", 2: "two", 3: "three"}
a := []string{"1:one", "2:two", "3:three"}
presentInMap(Sprintf("%v", m1), a, t)
presentInMap(Sprint(m1), a, t)
// Pointer to map prints the same but with initial &.
if !strings.HasPrefix(Sprint(&m1), "&") {
t.Errorf("no initial & for address of map")
}
presentInMap(Sprintf("%v", &m1), a, t)
presentInMap(Sprint(&m1), a, t)
}
func TestEmptyMap(t *testing.T) {
const emptyMapStr = "map[]"
var m map[string]int
s := Sprint(m)
if s != emptyMapStr {
t.Errorf("nil map printed as %q not %q", s, emptyMapStr)
}
m = make(map[string]int)
s = Sprint(m)
if s != emptyMapStr {
t.Errorf("empty map printed as %q not %q", s, emptyMapStr)
}
}
// TestBlank checks that Sprint (and hence Print, Fprint) puts spaces in the
// right places, that is, between arg pairs in which neither is a string.
func TestBlank(t *testing.T) {
got := Sprint("<", 1, ">:", 1, 2, 3, "!")
expect := "<1>:1 2 3!"
if got != expect {
t.Errorf("got %q expected %q", got, expect)
}
}
// TestBlankln checks that Sprintln (and hence Println, Fprintln) puts spaces in
// the right places, that is, between all arg pairs.
func TestBlankln(t *testing.T) {
got := Sprintln("<", 1, ">:", 1, 2, 3, "!")
expect := "< 1 >: 1 2 3 !\n"
if got != expect {
t.Errorf("got %q expected %q", got, expect)
}
}
// TestFormatterPrintln checks Formatter with Sprint, Sprintln, Sprintf.
func TestFormatterPrintln(t *testing.T) {
f := F(1)
expect := "<v=F(1)>\n"
s := Sprint(f, "\n")
if s != expect {
t.Errorf("Sprint wrong with Formatter: expected %q got %q", expect, s)
}
s = Sprintln(f)
if s != expect {
t.Errorf("Sprintln wrong with Formatter: expected %q got %q", expect, s)
}
s = Sprintf("%v\n", f)
if s != expect {
t.Errorf("Sprintf wrong with Formatter: expected %q got %q", expect, s)
}
}
func args(a ...interface{}) []interface{} { return a }
var startests = []struct {
fmt string
in []interface{}
out string
}{
{"%*d", args(4, 42), " 42"},
{"%-*d", args(4, 42), "42 "},
{"%*d", args(-4, 42), "42 "},
{"%-*d", args(-4, 42), "42 "},
{"%.*d", args(4, 42), "0042"},
{"%*.*d", args(8, 4, 42), " 0042"},
{"%0*d", args(4, 42), "0042"},
// erroneous
{"%*d", args(nil, 42), "%!(BADWIDTH)42"},
{"%*d", args(int(1e7), 42), "%!(BADWIDTH)42"},
{"%*d", args(int(-1e7), 42), "%!(BADWIDTH)42"},
{"%.*d", args(nil, 42), "%!(BADPREC)42"},
{"%.*d", args(-1, 42), "%!(BADPREC)42"},
{"%.*d", args(int(1e7), 42), "%!(BADPREC)42"},
{"%*d", args(5, "foo"), "%!d(string= foo)"},
{"%*% %d", args(20, 5), "% 5"},
{"%*", args(4), "%!(NOVERB)"},
{"%*d", args(int32(4), 42), "%!(BADWIDTH)42"},
}
func TestWidthAndPrecision(t *testing.T) {
for _, tt := range startests {
s := Sprintf(tt.fmt, tt.in...)
if s != tt.out {
t.Errorf("%q: got %q expected %q", tt.fmt, s, tt.out)
}
}
}
// Panic is a type that panics in String.
type Panic struct {
message interface{}
}
// Value receiver.
func (p Panic) GoString() string {
panic(p.message)
}
// Value receiver.
func (p Panic) String() string {
panic(p.message)
}
// PanicF is a type that panics in Format.
type PanicF struct {
message interface{}
}
// Value receiver.
func (p PanicF) Format(f State, c rune) {
panic(p.message)
}
var panictests = []struct {
fmt string
in interface{}
out string
}{
// String
{"%s", (*Panic)(nil), "<nil>"}, // nil pointer special case
{"%s", Panic{io.ErrUnexpectedEOF}, "%!s(PANIC=unexpected EOF)"},
{"%s", Panic{3}, "%!s(PANIC=3)"},
// GoString
{"%#v", (*Panic)(nil), "<nil>"}, // nil pointer special case
{"%#v", Panic{io.ErrUnexpectedEOF}, "%!v(PANIC=unexpected EOF)"},
{"%#v", Panic{3}, "%!v(PANIC=3)"},
// Format
{"%s", (*PanicF)(nil), "<nil>"}, // nil pointer special case
{"%s", PanicF{io.ErrUnexpectedEOF}, "%!s(PANIC=unexpected EOF)"},
{"%s", PanicF{3}, "%!s(PANIC=3)"},
}
func TestPanics(t *testing.T) {
for i, tt := range panictests {
s := Sprintf(tt.fmt, tt.in)
if s != tt.out {
t.Errorf("%d: %q: got %q expected %q", i, tt.fmt, s, tt.out)
}
}
}
// recurCount tests that erroneous String routine doesn't cause fatal recursion.
var recurCount = 0
type Recur struct {
i int
failed *bool
}
func (r *Recur) String() string {
if recurCount++; recurCount > 10 {
*r.failed = true
return "FAIL"
}
// This will call badVerb. Before the fix, that would cause us to recur into
// this routine to print %!p(value). Now we don't call the user's method
// during an error.
return Sprintf("recur@%p value: %d", r, r.i)
}
func TestBadVerbRecursion(t *testing.T) {
failed := false
r := &Recur{3, &failed}
Sprintf("recur@%p value: %d\n", &r, r.i)
if failed {
t.Error("fail with pointer")
}
failed = false
r = &Recur{4, &failed}
Sprintf("recur@%p, value: %d\n", r, r.i)
if failed {
t.Error("fail with value")
}
}
func TestIsSpace(t *testing.T) {
// This tests the internal isSpace function.
// IsSpace = isSpace is defined in export_test.go.
for i := rune(0); i <= unicode.MaxRune; i++ {
if IsSpace(i) != unicode.IsSpace(i) {
t.Errorf("isSpace(%U) = %v, want %v", i, IsSpace(i), unicode.IsSpace(i))
}
}
}
func TestNilDoesNotBecomeTyped(t *testing.T) {
type A struct{}
type B struct{}
var a *A = nil
var b B = B{}
got := Sprintf("%s %s %s %s %s", nil, a, nil, b, nil) // go vet should complain about this line.
const expect = "%!s(<nil>) %!s(*fmt_test.A=<nil>) %!s(<nil>) {} %!s(<nil>)"
if got != expect {
t.Errorf("expected:\n\t%q\ngot:\n\t%q", expect, got)
}
}
var formatterFlagTests = []struct {
in string
val interface{}
out string
}{
// scalar values with the (unused by fmt) 'a' verb.
{"%a", flagPrinter{}, "[%a]"},
{"%-a", flagPrinter{}, "[%-a]"},
{"%+a", flagPrinter{}, "[%+a]"},
{"%#a", flagPrinter{}, "[%#a]"},
{"% a", flagPrinter{}, "[% a]"},
{"%0a", flagPrinter{}, "[%0a]"},
{"%1.2a", flagPrinter{}, "[%1.2a]"},
{"%-1.2a", flagPrinter{}, "[%-1.2a]"},
{"%+1.2a", flagPrinter{}, "[%+1.2a]"},
{"%-+1.2a", flagPrinter{}, "[%+-1.2a]"},
{"%-+1.2abc", flagPrinter{}, "[%+-1.2a]bc"},
{"%-1.2abc", flagPrinter{}, "[%-1.2a]bc"},
// composite values with the 'a' verb
{"%a", [1]flagPrinter{}, "[[%a]]"},
{"%-a", [1]flagPrinter{}, "[[%-a]]"},
{"%+a", [1]flagPrinter{}, "[[%+a]]"},
{"%#a", [1]flagPrinter{}, "[[%#a]]"},
{"% a", [1]flagPrinter{}, "[[% a]]"},
{"%0a", [1]flagPrinter{}, "[[%0a]]"},
{"%1.2a", [1]flagPrinter{}, "[[%1.2a]]"},
{"%-1.2a", [1]flagPrinter{}, "[[%-1.2a]]"},
{"%+1.2a", [1]flagPrinter{}, "[[%+1.2a]]"},
{"%-+1.2a", [1]flagPrinter{}, "[[%+-1.2a]]"},
{"%-+1.2abc", [1]flagPrinter{}, "[[%+-1.2a]]bc"},
{"%-1.2abc", [1]flagPrinter{}, "[[%-1.2a]]bc"},
// simple values with the 'v' verb
{"%v", flagPrinter{}, "[%v]"},
{"%-v", flagPrinter{}, "[%-v]"},
{"%+v", flagPrinter{}, "[%+v]"},
{"%#v", flagPrinter{}, "[%#v]"},
{"% v", flagPrinter{}, "[% v]"},
{"%0v", flagPrinter{}, "[%0v]"},
{"%1.2v", flagPrinter{}, "[%1.2v]"},
{"%-1.2v", flagPrinter{}, "[%-1.2v]"},
{"%+1.2v", flagPrinter{}, "[%+1.2v]"},
{"%-+1.2v", flagPrinter{}, "[%+-1.2v]"},
{"%-+1.2vbc", flagPrinter{}, "[%+-1.2v]bc"},
{"%-1.2vbc", flagPrinter{}, "[%-1.2v]bc"},
// composite values with the 'v' verb.
{"%v", [1]flagPrinter{}, "[[%v]]"},
{"%-v", [1]flagPrinter{}, "[[%-v]]"},
{"%+v", [1]flagPrinter{}, "[[%+v]]"},
{"%#v", [1]flagPrinter{}, "[1]fmt_test.flagPrinter{[%#v]}"},
{"% v", [1]flagPrinter{}, "[[% v]]"},
{"%0v", [1]flagPrinter{}, "[[%0v]]"},
{"%1.2v", [1]flagPrinter{}, "[[%1.2v]]"},
{"%-1.2v", [1]flagPrinter{}, "[[%-1.2v]]"},
{"%+1.2v", [1]flagPrinter{}, "[[%+1.2v]]"},
{"%-+1.2v", [1]flagPrinter{}, "[[%+-1.2v]]"},
{"%-+1.2vbc", [1]flagPrinter{}, "[[%+-1.2v]]bc"},
{"%-1.2vbc", [1]flagPrinter{}, "[[%-1.2v]]bc"},
}
func TestFormatterFlags(t *testing.T) {
for _, tt := range formatterFlagTests {
s := Sprintf(tt.in, tt.val)
if s != tt.out {
t.Errorf("Sprintf(%q, %T) = %q, want %q", tt.in, tt.val, s, tt.out)
}
}
}