func: Implement TextMarshaler for map keys
Tim Hockin
2 years ago
| 35 | 35 |
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import (
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"bytes"
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"encoding"
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"fmt"
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"path/filepath"
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"reflect"
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if i > 0 {
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buf.WriteByte(',')
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}
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// prettyWithFlags will produce already-escaped values
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keystr := f.prettyWithFlags(it.Key().Interface(), 0)
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if t.Key().Kind() != reflect.String {
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// JSON only does string keys. Unlike Go's standard JSON, we'll
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// convert just about anything to a string.
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// If a map key supports TextMarshaler, use it.
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keystr := ""
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if m, ok := it.Key().Interface().(encoding.TextMarshaler); ok {
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txt, err := m.MarshalText()
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if err != nil {
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keystr = fmt.Sprintf("<error-MarshalText: %s>", err.Error())
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} else {
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keystr = string(txt)
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}
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keystr = prettyString(keystr)
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} else {
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// prettyWithFlags will produce already-escaped values
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keystr = f.prettyWithFlags(it.Key().Interface(), 0)
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if t.Key().Kind() != reflect.String {
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// JSON only does string keys. Unlike Go's standard JSON, we'll
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// convert just about anything to a string.
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keystr = prettyString(keystr)
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}
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}
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buf.WriteString(keystr)
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buf.WriteByte(':')
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}
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func ptrstr(s string) *string {
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return &s
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}
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// point implements encoding.TextMarshaler and can be used as a map key.
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type point struct{ x, y int }
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func (p point) MarshalText() ([]byte, error) {
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return []byte(fmt.Sprintf("(%d, %d)", p.x, p.y)), nil
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}
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// pointErr implements encoding.TextMarshaler but returns an error.
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type pointErr struct{ x, y int }
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func (p pointErr) MarshalText() ([]byte, error) {
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return nil, fmt.Errorf("uh oh: %d, %d", p.x, p.y)
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}
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// Logging this should result in the MarshalLog() value.
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exp: `{"9.5":3}`,
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},
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{
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val: map[point]int{
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{x: 1, y: 2}: 3,
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},
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},
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{
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val: map[pointErr]int{
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{x: 1, y: 2}: 3,
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},
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exp: `{"<error-MarshalText: uh oh: 1, 2>":3}`,
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},
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{
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val: struct {
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X int `json:"x"`
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Y int `json:"y"`
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} else {
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jb, err := json.Marshal(tc.val)
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| 497 | 522 |
if err != nil {
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t.Fatalf("[%d]: unexpected error: %v", i, err)
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t.Fatalf("[%d]: unexpected error: %v\ngot: %q", i, err, ours)
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}
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want = string(jb)
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}
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