1090 lines
27 KiB
Go
1090 lines
27 KiB
Go
// 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
|
|
|
|
import (
|
|
"bytes"
|
|
"errors"
|
|
"io"
|
|
"os"
|
|
"reflect"
|
|
"sync"
|
|
"unicode"
|
|
"unicode/utf8"
|
|
)
|
|
|
|
// Some constants in the form of bytes, to avoid string overhead.
|
|
// Needlessly fastidious, I suppose.
|
|
var (
|
|
commaSpaceBytes = []byte(", ")
|
|
nilAngleBytes = []byte("<nil>")
|
|
nilParenBytes = []byte("(nil)")
|
|
nilBytes = []byte("nil")
|
|
mapBytes = []byte("map[")
|
|
missingBytes = []byte("(MISSING)")
|
|
panicBytes = []byte("(PANIC=")
|
|
extraBytes = []byte("%!(EXTRA ")
|
|
irparenBytes = []byte("i)")
|
|
bytesBytes = []byte("[]byte{")
|
|
widthBytes = []byte("%!(BADWIDTH)")
|
|
precBytes = []byte("%!(BADPREC)")
|
|
noVerbBytes = []byte("%!(NOVERB)")
|
|
)
|
|
|
|
// State represents the printer state passed to custom formatters.
|
|
// It provides access to the io.Writer interface plus information about
|
|
// the flags and options for the operand's format specifier.
|
|
type State interface {
|
|
// Write is the function to call to emit formatted output to be printed.
|
|
Write(b []byte) (ret int, err error)
|
|
// Width returns the value of the width option and whether it has been set.
|
|
Width() (wid int, ok bool)
|
|
// Precision returns the value of the precision option and whether it has been set.
|
|
Precision() (prec int, ok bool)
|
|
|
|
// Flag returns whether the flag c, a character, has been set.
|
|
Flag(c int) bool
|
|
}
|
|
|
|
// Formatter is the interface implemented by values with a custom formatter.
|
|
// The implementation of Format may call Sprintf or Fprintf(f) etc.
|
|
// to generate its output.
|
|
type Formatter interface {
|
|
Format(f State, c rune)
|
|
}
|
|
|
|
// Stringer is implemented by any value that has a String method,
|
|
// which defines the ``native'' format for that value.
|
|
// The String method is used to print values passed as an operand
|
|
// to a %s or %v format or to an unformatted printer such as Print.
|
|
type Stringer interface {
|
|
String() string
|
|
}
|
|
|
|
// GoStringer is implemented by any value that has a GoString method,
|
|
// which defines the Go syntax for that value.
|
|
// The GoString method is used to print values passed as an operand
|
|
// to a %#v format.
|
|
type GoStringer interface {
|
|
GoString() string
|
|
}
|
|
|
|
type pp struct {
|
|
n int
|
|
panicking bool
|
|
erroring bool // printing an error condition
|
|
buf bytes.Buffer
|
|
// field holds the current item, as an interface{}.
|
|
field interface{}
|
|
// value holds the current item, as a reflect.Value, and will be
|
|
// the zero Value if the item has not been reflected.
|
|
value reflect.Value
|
|
runeBuf [utf8.UTFMax]byte
|
|
fmt fmt
|
|
}
|
|
|
|
// A cache holds a set of reusable objects.
|
|
// The slice is a stack (LIFO).
|
|
// If more are needed, the cache creates them by calling new.
|
|
type cache struct {
|
|
mu sync.Mutex
|
|
saved []interface{}
|
|
new func() interface{}
|
|
}
|
|
|
|
func (c *cache) put(x interface{}) {
|
|
c.mu.Lock()
|
|
if len(c.saved) < cap(c.saved) {
|
|
c.saved = append(c.saved, x)
|
|
}
|
|
c.mu.Unlock()
|
|
}
|
|
|
|
func (c *cache) get() interface{} {
|
|
c.mu.Lock()
|
|
n := len(c.saved)
|
|
if n == 0 {
|
|
c.mu.Unlock()
|
|
return c.new()
|
|
}
|
|
x := c.saved[n-1]
|
|
c.saved = c.saved[0 : n-1]
|
|
c.mu.Unlock()
|
|
return x
|
|
}
|
|
|
|
func newCache(f func() interface{}) *cache {
|
|
return &cache{saved: make([]interface{}, 0, 100), new: f}
|
|
}
|
|
|
|
var ppFree = newCache(func() interface{} { return new(pp) })
|
|
|
|
// Allocate a new pp struct or grab a cached one.
|
|
func newPrinter() *pp {
|
|
p := ppFree.get().(*pp)
|
|
p.panicking = false
|
|
p.erroring = false
|
|
p.fmt.init(&p.buf)
|
|
return p
|
|
}
|
|
|
|
// Save used pp structs in ppFree; avoids an allocation per invocation.
|
|
func (p *pp) free() {
|
|
// Don't hold on to pp structs with large buffers.
|
|
if cap(p.buf.Bytes()) > 1024 {
|
|
return
|
|
}
|
|
p.buf.Reset()
|
|
p.field = nil
|
|
p.value = reflect.Value{}
|
|
ppFree.put(p)
|
|
}
|
|
|
|
func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
|
|
|
|
func (p *pp) Precision() (prec int, ok bool) { return p.fmt.prec, p.fmt.precPresent }
|
|
|
|
func (p *pp) Flag(b int) bool {
|
|
switch b {
|
|
case '-':
|
|
return p.fmt.minus
|
|
case '+':
|
|
return p.fmt.plus
|
|
case '#':
|
|
return p.fmt.sharp
|
|
case ' ':
|
|
return p.fmt.space
|
|
case '0':
|
|
return p.fmt.zero
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (p *pp) add(c rune) {
|
|
p.buf.WriteRune(c)
|
|
}
|
|
|
|
// Implement Write so we can call Fprintf on a pp (through State), for
|
|
// recursive use in custom verbs.
|
|
func (p *pp) Write(b []byte) (ret int, err error) {
|
|
return p.buf.Write(b)
|
|
}
|
|
|
|
// These routines end in 'f' and take a format string.
|
|
|
|
// Fprintf formats according to a format specifier and writes to w.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
|
|
p := newPrinter()
|
|
p.doPrintf(format, a)
|
|
n64, err := p.buf.WriteTo(w)
|
|
p.free()
|
|
return int(n64), err
|
|
}
|
|
|
|
// Printf formats according to a format specifier and writes to standard output.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Printf(format string, a ...interface{}) (n int, err error) {
|
|
return Fprintf(os.Stdout, format, a...)
|
|
}
|
|
|
|
// Sprintf formats according to a format specifier and returns the resulting string.
|
|
func Sprintf(format string, a ...interface{}) string {
|
|
p := newPrinter()
|
|
p.doPrintf(format, a)
|
|
s := p.buf.String()
|
|
p.free()
|
|
return s
|
|
}
|
|
|
|
// Errorf formats according to a format specifier and returns the string
|
|
// as a value that satisfies error.
|
|
func Errorf(format string, a ...interface{}) error {
|
|
return errors.New(Sprintf(format, a...))
|
|
}
|
|
|
|
// These routines do not take a format string
|
|
|
|
// Fprint formats using the default formats for its operands and writes to w.
|
|
// Spaces are added between operands when neither is a string.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Fprint(w io.Writer, a ...interface{}) (n int, err error) {
|
|
p := newPrinter()
|
|
p.doPrint(a, false, false)
|
|
n64, err := p.buf.WriteTo(w)
|
|
p.free()
|
|
return int(n64), err
|
|
}
|
|
|
|
// Print formats using the default formats for its operands and writes to standard output.
|
|
// Spaces are added between operands when neither is a string.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Print(a ...interface{}) (n int, err error) {
|
|
return Fprint(os.Stdout, a...)
|
|
}
|
|
|
|
// Sprint formats using the default formats for its operands and returns the resulting string.
|
|
// Spaces are added between operands when neither is a string.
|
|
func Sprint(a ...interface{}) string {
|
|
p := newPrinter()
|
|
p.doPrint(a, false, false)
|
|
s := p.buf.String()
|
|
p.free()
|
|
return s
|
|
}
|
|
|
|
// These routines end in 'ln', do not take a format string,
|
|
// always add spaces between operands, and add a newline
|
|
// after the last operand.
|
|
|
|
// Fprintln formats using the default formats for its operands and writes to w.
|
|
// Spaces are always added between operands and a newline is appended.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Fprintln(w io.Writer, a ...interface{}) (n int, err error) {
|
|
p := newPrinter()
|
|
p.doPrint(a, true, true)
|
|
n64, err := p.buf.WriteTo(w)
|
|
p.free()
|
|
return int(n64), err
|
|
}
|
|
|
|
// Println formats using the default formats for its operands and writes to standard output.
|
|
// Spaces are always added between operands and a newline is appended.
|
|
// It returns the number of bytes written and any write error encountered.
|
|
func Println(a ...interface{}) (n int, err error) {
|
|
return Fprintln(os.Stdout, a...)
|
|
}
|
|
|
|
// Sprintln formats using the default formats for its operands and returns the resulting string.
|
|
// Spaces are always added between operands and a newline is appended.
|
|
func Sprintln(a ...interface{}) string {
|
|
p := newPrinter()
|
|
p.doPrint(a, true, true)
|
|
s := p.buf.String()
|
|
p.free()
|
|
return s
|
|
}
|
|
|
|
// Get the i'th arg of the struct value.
|
|
// If the arg itself is an interface, return a value for
|
|
// the thing inside the interface, not the interface itself.
|
|
func getField(v reflect.Value, i int) reflect.Value {
|
|
val := v.Field(i)
|
|
if val.Kind() == reflect.Interface && !val.IsNil() {
|
|
val = val.Elem()
|
|
}
|
|
return val
|
|
}
|
|
|
|
// Convert ASCII to integer. n is 0 (and got is false) if no number present.
|
|
func parsenum(s string, start, end int) (num int, isnum bool, newi int) {
|
|
if start >= end {
|
|
return 0, false, end
|
|
}
|
|
for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ {
|
|
num = num*10 + int(s[newi]-'0')
|
|
isnum = true
|
|
}
|
|
return
|
|
}
|
|
|
|
func (p *pp) unknownType(v interface{}) {
|
|
if v == nil {
|
|
p.buf.Write(nilAngleBytes)
|
|
return
|
|
}
|
|
p.buf.WriteByte('?')
|
|
p.buf.WriteString(reflect.TypeOf(v).String())
|
|
p.buf.WriteByte('?')
|
|
}
|
|
|
|
func (p *pp) badVerb(verb rune) {
|
|
p.erroring = true
|
|
p.add('%')
|
|
p.add('!')
|
|
p.add(verb)
|
|
p.add('(')
|
|
switch {
|
|
case p.field != nil:
|
|
p.buf.WriteString(reflect.TypeOf(p.field).String())
|
|
p.add('=')
|
|
p.printField(p.field, 'v', false, false, 0)
|
|
case p.value.IsValid():
|
|
p.buf.WriteString(p.value.Type().String())
|
|
p.add('=')
|
|
p.printValue(p.value, 'v', false, false, 0)
|
|
default:
|
|
p.buf.Write(nilAngleBytes)
|
|
}
|
|
p.add(')')
|
|
p.erroring = false
|
|
}
|
|
|
|
func (p *pp) fmtBool(v bool, verb rune) {
|
|
switch verb {
|
|
case 't', 'v':
|
|
p.fmt.fmt_boolean(v)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
// fmtC formats a rune for the 'c' format.
|
|
func (p *pp) fmtC(c int64) {
|
|
r := rune(c) // Check for overflow.
|
|
if int64(r) != c {
|
|
r = utf8.RuneError
|
|
}
|
|
w := utf8.EncodeRune(p.runeBuf[0:utf8.UTFMax], r)
|
|
p.fmt.pad(p.runeBuf[0:w])
|
|
}
|
|
|
|
func (p *pp) fmtInt64(v int64, verb rune) {
|
|
switch verb {
|
|
case 'b':
|
|
p.fmt.integer(v, 2, signed, ldigits)
|
|
case 'c':
|
|
p.fmtC(v)
|
|
case 'd', 'v':
|
|
p.fmt.integer(v, 10, signed, ldigits)
|
|
case 'o':
|
|
p.fmt.integer(v, 8, signed, ldigits)
|
|
case 'q':
|
|
if 0 <= v && v <= unicode.MaxRune {
|
|
p.fmt.fmt_qc(v)
|
|
} else {
|
|
p.badVerb(verb)
|
|
}
|
|
case 'x':
|
|
p.fmt.integer(v, 16, signed, ldigits)
|
|
case 'U':
|
|
p.fmtUnicode(v)
|
|
case 'X':
|
|
p.fmt.integer(v, 16, signed, udigits)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
|
|
// not, as requested, by temporarily setting the sharp flag.
|
|
func (p *pp) fmt0x64(v uint64, leading0x bool) {
|
|
sharp := p.fmt.sharp
|
|
p.fmt.sharp = leading0x
|
|
p.fmt.integer(int64(v), 16, unsigned, ldigits)
|
|
p.fmt.sharp = sharp
|
|
}
|
|
|
|
// fmtUnicode formats a uint64 in U+1234 form by
|
|
// temporarily turning on the unicode flag and tweaking the precision.
|
|
func (p *pp) fmtUnicode(v int64) {
|
|
precPresent := p.fmt.precPresent
|
|
sharp := p.fmt.sharp
|
|
p.fmt.sharp = false
|
|
prec := p.fmt.prec
|
|
if !precPresent {
|
|
// If prec is already set, leave it alone; otherwise 4 is minimum.
|
|
p.fmt.prec = 4
|
|
p.fmt.precPresent = true
|
|
}
|
|
p.fmt.unicode = true // turn on U+
|
|
p.fmt.uniQuote = sharp
|
|
p.fmt.integer(int64(v), 16, unsigned, udigits)
|
|
p.fmt.unicode = false
|
|
p.fmt.uniQuote = false
|
|
p.fmt.prec = prec
|
|
p.fmt.precPresent = precPresent
|
|
p.fmt.sharp = sharp
|
|
}
|
|
|
|
func (p *pp) fmtUint64(v uint64, verb rune, goSyntax bool) {
|
|
switch verb {
|
|
case 'b':
|
|
p.fmt.integer(int64(v), 2, unsigned, ldigits)
|
|
case 'c':
|
|
p.fmtC(int64(v))
|
|
case 'd':
|
|
p.fmt.integer(int64(v), 10, unsigned, ldigits)
|
|
case 'v':
|
|
if goSyntax {
|
|
p.fmt0x64(v, true)
|
|
} else {
|
|
p.fmt.integer(int64(v), 10, unsigned, ldigits)
|
|
}
|
|
case 'o':
|
|
p.fmt.integer(int64(v), 8, unsigned, ldigits)
|
|
case 'q':
|
|
if 0 <= v && v <= unicode.MaxRune {
|
|
p.fmt.fmt_qc(int64(v))
|
|
} else {
|
|
p.badVerb(verb)
|
|
}
|
|
case 'x':
|
|
p.fmt.integer(int64(v), 16, unsigned, ldigits)
|
|
case 'X':
|
|
p.fmt.integer(int64(v), 16, unsigned, udigits)
|
|
case 'U':
|
|
p.fmtUnicode(int64(v))
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtFloat32(v float32, verb rune) {
|
|
switch verb {
|
|
case 'b':
|
|
p.fmt.fmt_fb32(v)
|
|
case 'e':
|
|
p.fmt.fmt_e32(v)
|
|
case 'E':
|
|
p.fmt.fmt_E32(v)
|
|
case 'f':
|
|
p.fmt.fmt_f32(v)
|
|
case 'g', 'v':
|
|
p.fmt.fmt_g32(v)
|
|
case 'G':
|
|
p.fmt.fmt_G32(v)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtFloat64(v float64, verb rune) {
|
|
switch verb {
|
|
case 'b':
|
|
p.fmt.fmt_fb64(v)
|
|
case 'e':
|
|
p.fmt.fmt_e64(v)
|
|
case 'E':
|
|
p.fmt.fmt_E64(v)
|
|
case 'f':
|
|
p.fmt.fmt_f64(v)
|
|
case 'g', 'v':
|
|
p.fmt.fmt_g64(v)
|
|
case 'G':
|
|
p.fmt.fmt_G64(v)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtComplex64(v complex64, verb rune) {
|
|
switch verb {
|
|
case 'e', 'E', 'f', 'F', 'g', 'G':
|
|
p.fmt.fmt_c64(v, verb)
|
|
case 'v':
|
|
p.fmt.fmt_c64(v, 'g')
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtComplex128(v complex128, verb rune) {
|
|
switch verb {
|
|
case 'e', 'E', 'f', 'F', 'g', 'G':
|
|
p.fmt.fmt_c128(v, verb)
|
|
case 'v':
|
|
p.fmt.fmt_c128(v, 'g')
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtString(v string, verb rune, goSyntax bool) {
|
|
switch verb {
|
|
case 'v':
|
|
if goSyntax {
|
|
p.fmt.fmt_q(v)
|
|
} else {
|
|
p.fmt.fmt_s(v)
|
|
}
|
|
case 's':
|
|
p.fmt.fmt_s(v)
|
|
case 'x':
|
|
p.fmt.fmt_sx(v, ldigits)
|
|
case 'X':
|
|
p.fmt.fmt_sx(v, udigits)
|
|
case 'q':
|
|
p.fmt.fmt_q(v)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtBytes(v []byte, verb rune, goSyntax bool, depth int) {
|
|
if verb == 'v' || verb == 'd' {
|
|
if goSyntax {
|
|
p.buf.Write(bytesBytes)
|
|
} else {
|
|
p.buf.WriteByte('[')
|
|
}
|
|
for i, c := range v {
|
|
if i > 0 {
|
|
if goSyntax {
|
|
p.buf.Write(commaSpaceBytes)
|
|
} else {
|
|
p.buf.WriteByte(' ')
|
|
}
|
|
}
|
|
p.printField(c, 'v', p.fmt.plus, goSyntax, depth+1)
|
|
}
|
|
if goSyntax {
|
|
p.buf.WriteByte('}')
|
|
} else {
|
|
p.buf.WriteByte(']')
|
|
}
|
|
return
|
|
}
|
|
s := string(v)
|
|
switch verb {
|
|
case 's':
|
|
p.fmt.fmt_s(s)
|
|
case 'x':
|
|
p.fmt.fmt_sx(s, ldigits)
|
|
case 'X':
|
|
p.fmt.fmt_sx(s, udigits)
|
|
case 'q':
|
|
p.fmt.fmt_q(s)
|
|
default:
|
|
p.badVerb(verb)
|
|
}
|
|
}
|
|
|
|
func (p *pp) fmtPointer(value reflect.Value, verb rune, goSyntax bool) {
|
|
var u uintptr
|
|
switch value.Kind() {
|
|
case reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr, reflect.Slice, reflect.UnsafePointer:
|
|
u = value.Pointer()
|
|
default:
|
|
p.badVerb(verb)
|
|
return
|
|
}
|
|
if goSyntax {
|
|
p.add('(')
|
|
p.buf.WriteString(value.Type().String())
|
|
p.add(')')
|
|
p.add('(')
|
|
if u == 0 {
|
|
p.buf.Write(nilBytes)
|
|
} else {
|
|
p.fmt0x64(uint64(u), true)
|
|
}
|
|
p.add(')')
|
|
} else {
|
|
p.fmt0x64(uint64(u), !p.fmt.sharp)
|
|
}
|
|
}
|
|
|
|
var (
|
|
intBits = reflect.TypeOf(0).Bits()
|
|
floatBits = reflect.TypeOf(0.0).Bits()
|
|
complexBits = reflect.TypeOf(1i).Bits()
|
|
uintptrBits = reflect.TypeOf(uintptr(0)).Bits()
|
|
)
|
|
|
|
func (p *pp) catchPanic(field interface{}, verb rune) {
|
|
if err := recover(); err != nil {
|
|
// If it's a nil pointer, just say "<nil>". The likeliest causes are a
|
|
// Stringer that fails to guard against nil or a nil pointer for a
|
|
// value receiver, and in either case, "<nil>" is a nice result.
|
|
if v := reflect.ValueOf(field); v.Kind() == reflect.Ptr && v.IsNil() {
|
|
p.buf.Write(nilAngleBytes)
|
|
return
|
|
}
|
|
// Otherwise print a concise panic message. Most of the time the panic
|
|
// value will print itself nicely.
|
|
if p.panicking {
|
|
// Nested panics; the recursion in printField cannot succeed.
|
|
panic(err)
|
|
}
|
|
p.buf.WriteByte('%')
|
|
p.add(verb)
|
|
p.buf.Write(panicBytes)
|
|
p.panicking = true
|
|
p.printField(err, 'v', false, false, 0)
|
|
p.panicking = false
|
|
p.buf.WriteByte(')')
|
|
}
|
|
}
|
|
|
|
func (p *pp) handleMethods(verb rune, plus, goSyntax bool, depth int) (wasString, handled bool) {
|
|
if p.erroring {
|
|
return
|
|
}
|
|
// Is it a Formatter?
|
|
if formatter, ok := p.field.(Formatter); ok {
|
|
handled = true
|
|
wasString = false
|
|
defer p.catchPanic(p.field, verb)
|
|
formatter.Format(p, verb)
|
|
return
|
|
}
|
|
// Must not touch flags before Formatter looks at them.
|
|
if plus {
|
|
p.fmt.plus = false
|
|
}
|
|
|
|
// If we're doing Go syntax and the field knows how to supply it, take care of it now.
|
|
if goSyntax {
|
|
p.fmt.sharp = false
|
|
if stringer, ok := p.field.(GoStringer); ok {
|
|
wasString = false
|
|
handled = true
|
|
defer p.catchPanic(p.field, verb)
|
|
// Print the result of GoString unadorned.
|
|
p.fmtString(stringer.GoString(), 's', false)
|
|
return
|
|
}
|
|
} else {
|
|
// If a string is acceptable according to the format, see if
|
|
// the value satisfies one of the string-valued interfaces.
|
|
// Println etc. set verb to %v, which is "stringable".
|
|
switch verb {
|
|
case 'v', 's', 'x', 'X', 'q':
|
|
// Is it an error or Stringer?
|
|
// The duplication in the bodies is necessary:
|
|
// setting wasString and handled, and deferring catchPanic,
|
|
// must happen before calling the method.
|
|
switch v := p.field.(type) {
|
|
case error:
|
|
wasString = false
|
|
handled = true
|
|
defer p.catchPanic(p.field, verb)
|
|
p.printField(v.Error(), verb, plus, false, depth)
|
|
return
|
|
|
|
case Stringer:
|
|
wasString = false
|
|
handled = true
|
|
defer p.catchPanic(p.field, verb)
|
|
p.printField(v.String(), verb, plus, false, depth)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
handled = false
|
|
return
|
|
}
|
|
|
|
func (p *pp) printField(field interface{}, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
|
|
if field == nil {
|
|
if verb == 'T' || verb == 'v' {
|
|
p.buf.Write(nilAngleBytes)
|
|
} else {
|
|
p.badVerb(verb)
|
|
}
|
|
return false
|
|
}
|
|
|
|
p.field = field
|
|
p.value = reflect.Value{}
|
|
// Special processing considerations.
|
|
// %T (the value's type) and %p (its address) are special; we always do them first.
|
|
switch verb {
|
|
case 'T':
|
|
p.printField(reflect.TypeOf(field).String(), 's', false, false, 0)
|
|
return false
|
|
case 'p':
|
|
p.fmtPointer(reflect.ValueOf(field), verb, goSyntax)
|
|
return false
|
|
}
|
|
|
|
if wasString, handled := p.handleMethods(verb, plus, goSyntax, depth); handled {
|
|
return wasString
|
|
}
|
|
|
|
// Some types can be done without reflection.
|
|
switch f := field.(type) {
|
|
case bool:
|
|
p.fmtBool(f, verb)
|
|
case float32:
|
|
p.fmtFloat32(f, verb)
|
|
case float64:
|
|
p.fmtFloat64(f, verb)
|
|
case complex64:
|
|
p.fmtComplex64(complex64(f), verb)
|
|
case complex128:
|
|
p.fmtComplex128(f, verb)
|
|
case int:
|
|
p.fmtInt64(int64(f), verb)
|
|
case int8:
|
|
p.fmtInt64(int64(f), verb)
|
|
case int16:
|
|
p.fmtInt64(int64(f), verb)
|
|
case int32:
|
|
p.fmtInt64(int64(f), verb)
|
|
case int64:
|
|
p.fmtInt64(f, verb)
|
|
case uint:
|
|
p.fmtUint64(uint64(f), verb, goSyntax)
|
|
case uint8:
|
|
p.fmtUint64(uint64(f), verb, goSyntax)
|
|
case uint16:
|
|
p.fmtUint64(uint64(f), verb, goSyntax)
|
|
case uint32:
|
|
p.fmtUint64(uint64(f), verb, goSyntax)
|
|
case uint64:
|
|
p.fmtUint64(f, verb, goSyntax)
|
|
case uintptr:
|
|
p.fmtUint64(uint64(f), verb, goSyntax)
|
|
case string:
|
|
p.fmtString(f, verb, goSyntax)
|
|
wasString = verb == 's' || verb == 'v'
|
|
case []byte:
|
|
p.fmtBytes(f, verb, goSyntax, depth)
|
|
wasString = verb == 's'
|
|
default:
|
|
// Need to use reflection
|
|
return p.printReflectValue(reflect.ValueOf(field), verb, plus, goSyntax, depth)
|
|
}
|
|
p.field = nil
|
|
return
|
|
}
|
|
|
|
// printValue is like printField but starts with a reflect value, not an interface{} value.
|
|
func (p *pp) printValue(value reflect.Value, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
|
|
if !value.IsValid() {
|
|
if verb == 'T' || verb == 'v' {
|
|
p.buf.Write(nilAngleBytes)
|
|
} else {
|
|
p.badVerb(verb)
|
|
}
|
|
return false
|
|
}
|
|
|
|
// Special processing considerations.
|
|
// %T (the value's type) and %p (its address) are special; we always do them first.
|
|
switch verb {
|
|
case 'T':
|
|
p.printField(value.Type().String(), 's', false, false, 0)
|
|
return false
|
|
case 'p':
|
|
p.fmtPointer(value, verb, goSyntax)
|
|
return false
|
|
}
|
|
|
|
// Handle values with special methods.
|
|
// Call always, even when field == nil, because handleMethods clears p.fmt.plus for us.
|
|
p.field = nil // Make sure it's cleared, for safety.
|
|
if value.CanInterface() {
|
|
p.field = value.Interface()
|
|
}
|
|
if wasString, handled := p.handleMethods(verb, plus, goSyntax, depth); handled {
|
|
return wasString
|
|
}
|
|
|
|
return p.printReflectValue(value, verb, plus, goSyntax, depth)
|
|
}
|
|
|
|
// printReflectValue is the fallback for both printField and printValue.
|
|
// It uses reflect to print the value.
|
|
func (p *pp) printReflectValue(value reflect.Value, verb rune, plus, goSyntax bool, depth int) (wasString bool) {
|
|
oldValue := p.value
|
|
p.value = value
|
|
BigSwitch:
|
|
switch f := value; f.Kind() {
|
|
case reflect.Bool:
|
|
p.fmtBool(f.Bool(), verb)
|
|
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
|
|
p.fmtInt64(f.Int(), verb)
|
|
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
|
|
p.fmtUint64(uint64(f.Uint()), verb, goSyntax)
|
|
case reflect.Float32, reflect.Float64:
|
|
if f.Type().Size() == 4 {
|
|
p.fmtFloat32(float32(f.Float()), verb)
|
|
} else {
|
|
p.fmtFloat64(float64(f.Float()), verb)
|
|
}
|
|
case reflect.Complex64, reflect.Complex128:
|
|
if f.Type().Size() == 8 {
|
|
p.fmtComplex64(complex64(f.Complex()), verb)
|
|
} else {
|
|
p.fmtComplex128(complex128(f.Complex()), verb)
|
|
}
|
|
case reflect.String:
|
|
p.fmtString(f.String(), verb, goSyntax)
|
|
case reflect.Map:
|
|
if goSyntax {
|
|
p.buf.WriteString(f.Type().String())
|
|
if f.IsNil() {
|
|
p.buf.WriteString("(nil)")
|
|
break
|
|
}
|
|
p.buf.WriteByte('{')
|
|
} else {
|
|
p.buf.Write(mapBytes)
|
|
}
|
|
keys := f.MapKeys()
|
|
for i, key := range keys {
|
|
if i > 0 {
|
|
if goSyntax {
|
|
p.buf.Write(commaSpaceBytes)
|
|
} else {
|
|
p.buf.WriteByte(' ')
|
|
}
|
|
}
|
|
p.printValue(key, verb, plus, goSyntax, depth+1)
|
|
p.buf.WriteByte(':')
|
|
p.printValue(f.MapIndex(key), verb, plus, goSyntax, depth+1)
|
|
}
|
|
if goSyntax {
|
|
p.buf.WriteByte('}')
|
|
} else {
|
|
p.buf.WriteByte(']')
|
|
}
|
|
case reflect.Struct:
|
|
if goSyntax {
|
|
p.buf.WriteString(value.Type().String())
|
|
}
|
|
p.add('{')
|
|
v := f
|
|
t := v.Type()
|
|
for i := 0; i < v.NumField(); i++ {
|
|
if i > 0 {
|
|
if goSyntax {
|
|
p.buf.Write(commaSpaceBytes)
|
|
} else {
|
|
p.buf.WriteByte(' ')
|
|
}
|
|
}
|
|
if plus || goSyntax {
|
|
if f := t.Field(i); f.Name != "" {
|
|
p.buf.WriteString(f.Name)
|
|
p.buf.WriteByte(':')
|
|
}
|
|
}
|
|
p.printValue(getField(v, i), verb, plus, goSyntax, depth+1)
|
|
}
|
|
p.buf.WriteByte('}')
|
|
case reflect.Interface:
|
|
value := f.Elem()
|
|
if !value.IsValid() {
|
|
if goSyntax {
|
|
p.buf.WriteString(f.Type().String())
|
|
p.buf.Write(nilParenBytes)
|
|
} else {
|
|
p.buf.Write(nilAngleBytes)
|
|
}
|
|
} else {
|
|
wasString = p.printValue(value, verb, plus, goSyntax, depth+1)
|
|
}
|
|
case reflect.Array, reflect.Slice:
|
|
// Byte slices are special.
|
|
if f.Type().Elem().Kind() == reflect.Uint8 {
|
|
// We know it's a slice of bytes, but we also know it does not have static type
|
|
// []byte, or it would have been caught above. Therefore we cannot convert
|
|
// it directly in the (slightly) obvious way: f.Interface().([]byte); it doesn't have
|
|
// that type, and we can't write an expression of the right type and do a
|
|
// conversion because we don't have a static way to write the right type.
|
|
// So we build a slice by hand. This is a rare case but it would be nice
|
|
// if reflection could help a little more.
|
|
bytes := make([]byte, f.Len())
|
|
for i := range bytes {
|
|
bytes[i] = byte(f.Index(i).Uint())
|
|
}
|
|
p.fmtBytes(bytes, verb, goSyntax, depth)
|
|
wasString = verb == 's'
|
|
break
|
|
}
|
|
if goSyntax {
|
|
p.buf.WriteString(value.Type().String())
|
|
if f.Kind() == reflect.Slice && f.IsNil() {
|
|
p.buf.WriteString("(nil)")
|
|
break
|
|
}
|
|
p.buf.WriteByte('{')
|
|
} else {
|
|
p.buf.WriteByte('[')
|
|
}
|
|
for i := 0; i < f.Len(); i++ {
|
|
if i > 0 {
|
|
if goSyntax {
|
|
p.buf.Write(commaSpaceBytes)
|
|
} else {
|
|
p.buf.WriteByte(' ')
|
|
}
|
|
}
|
|
p.printValue(f.Index(i), verb, plus, goSyntax, depth+1)
|
|
}
|
|
if goSyntax {
|
|
p.buf.WriteByte('}')
|
|
} else {
|
|
p.buf.WriteByte(']')
|
|
}
|
|
case reflect.Ptr:
|
|
v := f.Pointer()
|
|
// pointer to array or slice or struct? ok at top level
|
|
// but not embedded (avoid loops)
|
|
if v != 0 && depth == 0 {
|
|
switch a := f.Elem(); a.Kind() {
|
|
case reflect.Array, reflect.Slice:
|
|
p.buf.WriteByte('&')
|
|
p.printValue(a, verb, plus, goSyntax, depth+1)
|
|
break BigSwitch
|
|
case reflect.Struct:
|
|
p.buf.WriteByte('&')
|
|
p.printValue(a, verb, plus, goSyntax, depth+1)
|
|
break BigSwitch
|
|
}
|
|
}
|
|
if goSyntax {
|
|
p.buf.WriteByte('(')
|
|
p.buf.WriteString(value.Type().String())
|
|
p.buf.WriteByte(')')
|
|
p.buf.WriteByte('(')
|
|
if v == 0 {
|
|
p.buf.Write(nilBytes)
|
|
} else {
|
|
p.fmt0x64(uint64(v), true)
|
|
}
|
|
p.buf.WriteByte(')')
|
|
break
|
|
}
|
|
if v == 0 {
|
|
p.buf.Write(nilAngleBytes)
|
|
break
|
|
}
|
|
p.fmt0x64(uint64(v), true)
|
|
case reflect.Chan, reflect.Func, reflect.UnsafePointer:
|
|
p.fmtPointer(value, verb, goSyntax)
|
|
default:
|
|
p.unknownType(f)
|
|
}
|
|
p.value = oldValue
|
|
return wasString
|
|
}
|
|
|
|
// intFromArg gets the fieldnumth element of a. On return, isInt reports whether the argument has type int.
|
|
func intFromArg(a []interface{}, end, i, fieldnum int) (num int, isInt bool, newi, newfieldnum int) {
|
|
newi, newfieldnum = end, fieldnum
|
|
if i < end && fieldnum < len(a) {
|
|
num, isInt = a[fieldnum].(int)
|
|
newi, newfieldnum = i+1, fieldnum+1
|
|
}
|
|
return
|
|
}
|
|
|
|
func (p *pp) doPrintf(format string, a []interface{}) {
|
|
end := len(format)
|
|
fieldnum := 0 // we process one field per non-trivial format
|
|
for i := 0; i < end; {
|
|
lasti := i
|
|
for i < end && format[i] != '%' {
|
|
i++
|
|
}
|
|
if i > lasti {
|
|
p.buf.WriteString(format[lasti:i])
|
|
}
|
|
if i >= end {
|
|
// done processing format string
|
|
break
|
|
}
|
|
|
|
// Process one verb
|
|
i++
|
|
// flags and widths
|
|
p.fmt.clearflags()
|
|
F:
|
|
for ; i < end; i++ {
|
|
switch format[i] {
|
|
case '#':
|
|
p.fmt.sharp = true
|
|
case '0':
|
|
p.fmt.zero = true
|
|
case '+':
|
|
p.fmt.plus = true
|
|
case '-':
|
|
p.fmt.minus = true
|
|
case ' ':
|
|
p.fmt.space = true
|
|
default:
|
|
break F
|
|
}
|
|
}
|
|
// do we have width?
|
|
if i < end && format[i] == '*' {
|
|
p.fmt.wid, p.fmt.widPresent, i, fieldnum = intFromArg(a, end, i, fieldnum)
|
|
if !p.fmt.widPresent {
|
|
p.buf.Write(widthBytes)
|
|
}
|
|
} else {
|
|
p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end)
|
|
}
|
|
// do we have precision?
|
|
if i < end && format[i] == '.' {
|
|
if format[i+1] == '*' {
|
|
p.fmt.prec, p.fmt.precPresent, i, fieldnum = intFromArg(a, end, i+1, fieldnum)
|
|
if !p.fmt.precPresent {
|
|
p.buf.Write(precBytes)
|
|
}
|
|
} else {
|
|
p.fmt.prec, p.fmt.precPresent, i = parsenum(format, i+1, end)
|
|
if !p.fmt.precPresent {
|
|
p.fmt.prec = 0
|
|
p.fmt.precPresent = true
|
|
}
|
|
}
|
|
}
|
|
if i >= end {
|
|
p.buf.Write(noVerbBytes)
|
|
continue
|
|
}
|
|
c, w := utf8.DecodeRuneInString(format[i:])
|
|
i += w
|
|
// percent is special - absorbs no operand
|
|
if c == '%' {
|
|
p.buf.WriteByte('%') // We ignore width and prec.
|
|
continue
|
|
}
|
|
if fieldnum >= len(a) { // out of operands
|
|
p.buf.WriteByte('%')
|
|
p.add(c)
|
|
p.buf.Write(missingBytes)
|
|
continue
|
|
}
|
|
field := a[fieldnum]
|
|
fieldnum++
|
|
|
|
goSyntax := c == 'v' && p.fmt.sharp
|
|
plus := c == 'v' && p.fmt.plus
|
|
p.printField(field, c, plus, goSyntax, 0)
|
|
}
|
|
|
|
if fieldnum < len(a) {
|
|
p.buf.Write(extraBytes)
|
|
for ; fieldnum < len(a); fieldnum++ {
|
|
field := a[fieldnum]
|
|
if field != nil {
|
|
p.buf.WriteString(reflect.TypeOf(field).String())
|
|
p.buf.WriteByte('=')
|
|
}
|
|
p.printField(field, 'v', false, false, 0)
|
|
if fieldnum+1 < len(a) {
|
|
p.buf.Write(commaSpaceBytes)
|
|
}
|
|
}
|
|
p.buf.WriteByte(')')
|
|
}
|
|
}
|
|
|
|
func (p *pp) doPrint(a []interface{}, addspace, addnewline bool) {
|
|
prevString := false
|
|
for fieldnum := 0; fieldnum < len(a); fieldnum++ {
|
|
p.fmt.clearflags()
|
|
// always add spaces if we're doing println
|
|
field := a[fieldnum]
|
|
if fieldnum > 0 {
|
|
isString := field != nil && reflect.TypeOf(field).Kind() == reflect.String
|
|
if addspace || !isString && !prevString {
|
|
p.buf.WriteByte(' ')
|
|
}
|
|
}
|
|
prevString = p.printField(field, 'v', false, false, 0)
|
|
}
|
|
if addnewline {
|
|
p.buf.WriteByte('\n')
|
|
}
|
|
}
|