forked from Shiloh/githaven
328 lines
7.1 KiB
Go
Vendored
328 lines
7.1 KiB
Go
Vendored
package pretty
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
"reflect"
|
|
"strconv"
|
|
"text/tabwriter"
|
|
|
|
"github.com/kr/text"
|
|
)
|
|
|
|
type formatter struct {
|
|
v reflect.Value
|
|
force bool
|
|
quote bool
|
|
}
|
|
|
|
// Formatter makes a wrapper, f, that will format x as go source with line
|
|
// breaks and tabs. Object f responds to the "%v" formatting verb when both the
|
|
// "#" and " " (space) flags are set, for example:
|
|
//
|
|
// fmt.Sprintf("%# v", Formatter(x))
|
|
//
|
|
// If one of these two flags is not set, or any other verb is used, f will
|
|
// format x according to the usual rules of package fmt.
|
|
// In particular, if x satisfies fmt.Formatter, then x.Format will be called.
|
|
func Formatter(x interface{}) (f fmt.Formatter) {
|
|
return formatter{v: reflect.ValueOf(x), quote: true}
|
|
}
|
|
|
|
func (fo formatter) String() string {
|
|
return fmt.Sprint(fo.v.Interface()) // unwrap it
|
|
}
|
|
|
|
func (fo formatter) passThrough(f fmt.State, c rune) {
|
|
s := "%"
|
|
for i := 0; i < 128; i++ {
|
|
if f.Flag(i) {
|
|
s += string(i)
|
|
}
|
|
}
|
|
if w, ok := f.Width(); ok {
|
|
s += fmt.Sprintf("%d", w)
|
|
}
|
|
if p, ok := f.Precision(); ok {
|
|
s += fmt.Sprintf(".%d", p)
|
|
}
|
|
s += string(c)
|
|
fmt.Fprintf(f, s, fo.v.Interface())
|
|
}
|
|
|
|
func (fo formatter) Format(f fmt.State, c rune) {
|
|
if fo.force || c == 'v' && f.Flag('#') && f.Flag(' ') {
|
|
w := tabwriter.NewWriter(f, 4, 4, 1, ' ', 0)
|
|
p := &printer{tw: w, Writer: w, visited: make(map[visit]int)}
|
|
p.printValue(fo.v, true, fo.quote)
|
|
w.Flush()
|
|
return
|
|
}
|
|
fo.passThrough(f, c)
|
|
}
|
|
|
|
type printer struct {
|
|
io.Writer
|
|
tw *tabwriter.Writer
|
|
visited map[visit]int
|
|
depth int
|
|
}
|
|
|
|
func (p *printer) indent() *printer {
|
|
q := *p
|
|
q.tw = tabwriter.NewWriter(p.Writer, 4, 4, 1, ' ', 0)
|
|
q.Writer = text.NewIndentWriter(q.tw, []byte{'\t'})
|
|
return &q
|
|
}
|
|
|
|
func (p *printer) printInline(v reflect.Value, x interface{}, showType bool) {
|
|
if showType {
|
|
io.WriteString(p, v.Type().String())
|
|
fmt.Fprintf(p, "(%#v)", x)
|
|
} else {
|
|
fmt.Fprintf(p, "%#v", x)
|
|
}
|
|
}
|
|
|
|
// printValue must keep track of already-printed pointer values to avoid
|
|
// infinite recursion.
|
|
type visit struct {
|
|
v uintptr
|
|
typ reflect.Type
|
|
}
|
|
|
|
func (p *printer) printValue(v reflect.Value, showType, quote bool) {
|
|
if p.depth > 10 {
|
|
io.WriteString(p, "!%v(DEPTH EXCEEDED)")
|
|
return
|
|
}
|
|
|
|
switch v.Kind() {
|
|
case reflect.Bool:
|
|
p.printInline(v, v.Bool(), showType)
|
|
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
|
|
p.printInline(v, v.Int(), showType)
|
|
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
|
|
p.printInline(v, v.Uint(), showType)
|
|
case reflect.Float32, reflect.Float64:
|
|
p.printInline(v, v.Float(), showType)
|
|
case reflect.Complex64, reflect.Complex128:
|
|
fmt.Fprintf(p, "%#v", v.Complex())
|
|
case reflect.String:
|
|
p.fmtString(v.String(), quote)
|
|
case reflect.Map:
|
|
t := v.Type()
|
|
if showType {
|
|
io.WriteString(p, t.String())
|
|
}
|
|
writeByte(p, '{')
|
|
if nonzero(v) {
|
|
expand := !canInline(v.Type())
|
|
pp := p
|
|
if expand {
|
|
writeByte(p, '\n')
|
|
pp = p.indent()
|
|
}
|
|
keys := v.MapKeys()
|
|
for i := 0; i < v.Len(); i++ {
|
|
k := keys[i]
|
|
mv := v.MapIndex(k)
|
|
pp.printValue(k, false, true)
|
|
writeByte(pp, ':')
|
|
if expand {
|
|
writeByte(pp, '\t')
|
|
}
|
|
showTypeInStruct := t.Elem().Kind() == reflect.Interface
|
|
pp.printValue(mv, showTypeInStruct, true)
|
|
if expand {
|
|
io.WriteString(pp, ",\n")
|
|
} else if i < v.Len()-1 {
|
|
io.WriteString(pp, ", ")
|
|
}
|
|
}
|
|
if expand {
|
|
pp.tw.Flush()
|
|
}
|
|
}
|
|
writeByte(p, '}')
|
|
case reflect.Struct:
|
|
t := v.Type()
|
|
if v.CanAddr() {
|
|
addr := v.UnsafeAddr()
|
|
vis := visit{addr, t}
|
|
if vd, ok := p.visited[vis]; ok && vd < p.depth {
|
|
p.fmtString(t.String()+"{(CYCLIC REFERENCE)}", false)
|
|
break // don't print v again
|
|
}
|
|
p.visited[vis] = p.depth
|
|
}
|
|
|
|
if showType {
|
|
io.WriteString(p, t.String())
|
|
}
|
|
writeByte(p, '{')
|
|
if nonzero(v) {
|
|
expand := !canInline(v.Type())
|
|
pp := p
|
|
if expand {
|
|
writeByte(p, '\n')
|
|
pp = p.indent()
|
|
}
|
|
for i := 0; i < v.NumField(); i++ {
|
|
showTypeInStruct := true
|
|
if f := t.Field(i); f.Name != "" {
|
|
io.WriteString(pp, f.Name)
|
|
writeByte(pp, ':')
|
|
if expand {
|
|
writeByte(pp, '\t')
|
|
}
|
|
showTypeInStruct = labelType(f.Type)
|
|
}
|
|
pp.printValue(getField(v, i), showTypeInStruct, true)
|
|
if expand {
|
|
io.WriteString(pp, ",\n")
|
|
} else if i < v.NumField()-1 {
|
|
io.WriteString(pp, ", ")
|
|
}
|
|
}
|
|
if expand {
|
|
pp.tw.Flush()
|
|
}
|
|
}
|
|
writeByte(p, '}')
|
|
case reflect.Interface:
|
|
switch e := v.Elem(); {
|
|
case e.Kind() == reflect.Invalid:
|
|
io.WriteString(p, "nil")
|
|
case e.IsValid():
|
|
pp := *p
|
|
pp.depth++
|
|
pp.printValue(e, showType, true)
|
|
default:
|
|
io.WriteString(p, v.Type().String())
|
|
io.WriteString(p, "(nil)")
|
|
}
|
|
case reflect.Array, reflect.Slice:
|
|
t := v.Type()
|
|
if showType {
|
|
io.WriteString(p, t.String())
|
|
}
|
|
if v.Kind() == reflect.Slice && v.IsNil() && showType {
|
|
io.WriteString(p, "(nil)")
|
|
break
|
|
}
|
|
if v.Kind() == reflect.Slice && v.IsNil() {
|
|
io.WriteString(p, "nil")
|
|
break
|
|
}
|
|
writeByte(p, '{')
|
|
expand := !canInline(v.Type())
|
|
pp := p
|
|
if expand {
|
|
writeByte(p, '\n')
|
|
pp = p.indent()
|
|
}
|
|
for i := 0; i < v.Len(); i++ {
|
|
showTypeInSlice := t.Elem().Kind() == reflect.Interface
|
|
pp.printValue(v.Index(i), showTypeInSlice, true)
|
|
if expand {
|
|
io.WriteString(pp, ",\n")
|
|
} else if i < v.Len()-1 {
|
|
io.WriteString(pp, ", ")
|
|
}
|
|
}
|
|
if expand {
|
|
pp.tw.Flush()
|
|
}
|
|
writeByte(p, '}')
|
|
case reflect.Ptr:
|
|
e := v.Elem()
|
|
if !e.IsValid() {
|
|
writeByte(p, '(')
|
|
io.WriteString(p, v.Type().String())
|
|
io.WriteString(p, ")(nil)")
|
|
} else {
|
|
pp := *p
|
|
pp.depth++
|
|
writeByte(pp, '&')
|
|
pp.printValue(e, true, true)
|
|
}
|
|
case reflect.Chan:
|
|
x := v.Pointer()
|
|
if showType {
|
|
writeByte(p, '(')
|
|
io.WriteString(p, v.Type().String())
|
|
fmt.Fprintf(p, ")(%#v)", x)
|
|
} else {
|
|
fmt.Fprintf(p, "%#v", x)
|
|
}
|
|
case reflect.Func:
|
|
io.WriteString(p, v.Type().String())
|
|
io.WriteString(p, " {...}")
|
|
case reflect.UnsafePointer:
|
|
p.printInline(v, v.Pointer(), showType)
|
|
case reflect.Invalid:
|
|
io.WriteString(p, "nil")
|
|
}
|
|
}
|
|
|
|
func canInline(t reflect.Type) bool {
|
|
switch t.Kind() {
|
|
case reflect.Map:
|
|
return !canExpand(t.Elem())
|
|
case reflect.Struct:
|
|
for i := 0; i < t.NumField(); i++ {
|
|
if canExpand(t.Field(i).Type) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
case reflect.Interface:
|
|
return false
|
|
case reflect.Array, reflect.Slice:
|
|
return !canExpand(t.Elem())
|
|
case reflect.Ptr:
|
|
return false
|
|
case reflect.Chan, reflect.Func, reflect.UnsafePointer:
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func canExpand(t reflect.Type) bool {
|
|
switch t.Kind() {
|
|
case reflect.Map, reflect.Struct,
|
|
reflect.Interface, reflect.Array, reflect.Slice,
|
|
reflect.Ptr:
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func labelType(t reflect.Type) bool {
|
|
switch t.Kind() {
|
|
case reflect.Interface, reflect.Struct:
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (p *printer) fmtString(s string, quote bool) {
|
|
if quote {
|
|
s = strconv.Quote(s)
|
|
}
|
|
io.WriteString(p, s)
|
|
}
|
|
|
|
func writeByte(w io.Writer, b byte) {
|
|
w.Write([]byte{b})
|
|
}
|
|
|
|
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
|
|
}
|