encoding/json: add Decoder.InputOffset for offset access

rentziass · ianlancetaylor · commit ba108c93b864 · 2019-10-11T16:34:01.000Z
This makes Decoder.offset public while renaming it to Decoder.InputOffset to match encoding/xml Decoder API Code changes made by Adam Stankiewicz [sheerun@sher.pl] Fixes golang#29688 Change-Id: I86dbfd2b2da80160846e92bfa580c53d8d45e2db Reviewed-on: https://go-review.googlesource.com/c/go/+/200677 Run-TryBot: Johan Brandhorst <johan.brandhorst@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/encoding/json/stream.go b/src/encoding/json/stream.go
@@ -56,7 +56,7 @@ func (dec *Decoder) Decode(v interface{}) error {
 	}
 
 	if !dec.tokenValueAllowed() {
-		return &SyntaxError{msg: "not at beginning of value", Offset: dec.offset()}
+		return &SyntaxError{msg: "not at beginning of value", Offset: dec.InputOffset()}
 	}
 
 	// Read whole value into buffer.
@@ -314,7 +314,7 @@ func (dec *Decoder) tokenPrepareForDecode() error {
 			return err
 		}
 		if c != ',' {
-			return &SyntaxError{"expected comma after array element", dec.offset()}
+			return &SyntaxError{"expected comma after array element", dec.InputOffset()}
 		}
 		dec.scanp++
 		dec.tokenState = tokenArrayValue
@@ -324,7 +324,7 @@ func (dec *Decoder) tokenPrepareForDecode() error {
 			return err
 		}
 		if c != ':' {
-			return &SyntaxError{"expected colon after object key", dec.offset()}
+			return &SyntaxError{"expected colon after object key", dec.InputOffset()}
 		}
 		dec.scanp++
 		dec.tokenState = tokenObjectValue
@@ -477,7 +477,7 @@ func (dec *Decoder) tokenError(c byte) (Token, error) {
 	case tokenObjectComma:
 		context = " after object key:value pair"
 	}
-	return nil, &SyntaxError{"invalid character " + quoteChar(c) + context, dec.offset()}
+	return nil, &SyntaxError{"invalid character " + quoteChar(c) + context, dec.InputOffset()}
 }
 
 // More reports whether there is another element in the
@@ -506,6 +506,9 @@ func (dec *Decoder) peek() (byte, error) {
 	}
 }
 
-func (dec *Decoder) offset() int64 {
+// InputOffset returns the input stream byte offset of the current decoder position.
+// The offset gives the location of the end of the most recently returned token
+// and the beginning of the next token.
+func (dec *Decoder) InputOffset() int64 {
 	return dec.scanned + int64(dec.scanp)
 }

Original file line number	Diff line number	Diff line change
`@@ -56,7 +56,7 @@ func (dec *Decoder) Decode(v interface{}) error {`
`56`	`56`	`}`
`57`	`57`
`58`	`58`	`if !dec.tokenValueAllowed() {`
`59`		`- return &SyntaxError{msg: "not at beginning of value", Offset: dec.offset()}`
	`59`	`+ return &SyntaxError{msg: "not at beginning of value", Offset: dec.InputOffset()}`
`60`	`60`	`}`
`61`	`61`
`62`	`62`	`// Read whole value into buffer.`
`@@ -314,7 +314,7 @@ func (dec *Decoder) tokenPrepareForDecode() error {`
`314`	`314`	`return err`
`315`	`315`	`}`
`316`	`316`	`if c != ',' {`
`317`		`- return &SyntaxError{"expected comma after array element", dec.offset()}`
	`317`	`+ return &SyntaxError{"expected comma after array element", dec.InputOffset()}`
`318`	`318`	`}`
`319`	`319`	`dec.scanp++`
`320`	`320`	`dec.tokenState = tokenArrayValue`
`@@ -324,7 +324,7 @@ func (dec *Decoder) tokenPrepareForDecode() error {`
`324`	`324`	`return err`
`325`	`325`	`}`
`326`	`326`	`if c != ':' {`
`327`		`- return &SyntaxError{"expected colon after object key", dec.offset()}`
	`327`	`+ return &SyntaxError{"expected colon after object key", dec.InputOffset()}`
`328`	`328`	`}`
`329`	`329`	`dec.scanp++`
`330`	`330`	`dec.tokenState = tokenObjectValue`
`@@ -477,7 +477,7 @@ func (dec *Decoder) tokenError(c byte) (Token, error) {`
`477`	`477`	`case tokenObjectComma:`
`478`	`478`	`context = " after object key:value pair"`
`479`	`479`	`}`
`480`		`- return nil, &SyntaxError{"invalid character " + quoteChar(c) + context, dec.offset()}`
	`480`	`+ return nil, &SyntaxError{"invalid character " + quoteChar(c) + context, dec.InputOffset()}`
`481`	`481`	`}`
`482`	`482`
`483`	`483`	`// More reports whether there is another element in the`
`@@ -506,6 +506,9 @@ func (dec *Decoder) peek() (byte, error) {`
`506`	`506`	`}`
`507`	`507`	`}`
`508`	`508`
`509`		`-func (dec *Decoder) offset() int64 {`
	`509`	`+// InputOffset returns the input stream byte offset of the current decoder position.`
	`510`	`+// The offset gives the location of the end of the most recently returned token`
	`511`	`+// and the beginning of the next token.`
	`512`	`+func (dec *Decoder) InputOffset() int64 {`
`510`	`513`	`return dec.scanned + int64(dec.scanp)`
`511`	`514`	`}`