mirror of https://github.com/miguelmota/cointop
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
59 lines
1.6 KiB
Go
59 lines
1.6 KiB
Go
/*
|
|
Copyright 2011 Google Inc.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
// Package errorutil helps make better error messages.
|
|
package errorutil // import "go4.org/errorutil"
|
|
|
|
import (
|
|
"bufio"
|
|
"bytes"
|
|
"fmt"
|
|
"io"
|
|
"strings"
|
|
)
|
|
|
|
// HighlightBytePosition takes a reader and the location in bytes of a parse
|
|
// error (for instance, from json.SyntaxError.Offset) and returns the line, column,
|
|
// and pretty-printed context around the error with an arrow indicating the exact
|
|
// position of the syntax error.
|
|
func HighlightBytePosition(f io.Reader, pos int64) (line, col int, highlight string) {
|
|
line = 1
|
|
br := bufio.NewReader(f)
|
|
lastLine := ""
|
|
thisLine := new(bytes.Buffer)
|
|
for n := int64(0); n < pos; n++ {
|
|
b, err := br.ReadByte()
|
|
if err != nil {
|
|
break
|
|
}
|
|
if b == '\n' {
|
|
lastLine = thisLine.String()
|
|
thisLine.Reset()
|
|
line++
|
|
col = 1
|
|
} else {
|
|
col++
|
|
thisLine.WriteByte(b)
|
|
}
|
|
}
|
|
if line > 1 {
|
|
highlight += fmt.Sprintf("%5d: %s\n", line-1, lastLine)
|
|
}
|
|
highlight += fmt.Sprintf("%5d: %s\n", line, thisLine.String())
|
|
highlight += fmt.Sprintf("%s^\n", strings.Repeat(" ", col+5))
|
|
return
|
|
}
|