hugo/common/herrors/error_locator.go
2023-03-15 08:54:34 +01:00

177 lines
4.4 KiB
Go

// Copyright 2022 The Hugo Authors. All rights reserved.
//
// 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 herrors contains common Hugo errors and error related utilities.
package herrors
import (
"io"
"path/filepath"
"strings"
"github.com/gohugoio/hugo/common/text"
)
// LineMatcher contains the elements used to match an error to a line
type LineMatcher struct {
Position text.Position
Error error
LineNumber int
Offset int
Line string
}
// LineMatcherFn is used to match a line with an error.
// It returns the column number or 0 if the line was found, but column could not be determinde. Returns -1 if no line match.
type LineMatcherFn func(m LineMatcher) int
// SimpleLineMatcher simply matches by line number.
var SimpleLineMatcher = func(m LineMatcher) int {
if m.Position.LineNumber == m.LineNumber {
// We found the line, but don't know the column.
return 0
}
return -1
}
// NopLineMatcher is a matcher that always returns 1.
// This will effectively give line 1, column 1.
var NopLineMatcher = func(m LineMatcher) int {
return 1
}
// OffsetMatcher is a line matcher that matches by offset.
var OffsetMatcher = func(m LineMatcher) int {
if m.Offset+len(m.Line) >= m.Position.Offset {
// We found the line, but return 0 to signal that we want to determine
// the column from the error.
return 0
}
return -1
}
// ContainsMatcher is a line matcher that matches by line content.
func ContainsMatcher(text string) func(m LineMatcher) int {
return func(m LineMatcher) int {
if idx := strings.Index(m.Line, text); idx != -1 {
return idx + 1
}
return -1
}
}
// ErrorContext contains contextual information about an error. This will
// typically be the lines surrounding some problem in a file.
type ErrorContext struct {
// If a match will contain the matched line and up to 2 lines before and after.
// Will be empty if no match.
Lines []string
// The position of the error in the Lines above. 0 based.
LinesPos int
// The position of the content in the file. Note that this may be different from the error's position set
// in FileError.
Position text.Position
// The lexer to use for syntax highlighting.
// https://gohugo.io/content-management/syntax-highlighting/#list-of-chroma-highlighting-languages
ChromaLexer string
}
func chromaLexerFromType(fileType string) string {
switch fileType {
case "html", "htm":
return "go-html-template"
}
return fileType
}
func extNoDelimiter(filename string) string {
return strings.TrimPrefix(filepath.Ext(filename), ".")
}
func chromaLexerFromFilename(filename string) string {
if strings.Contains(filename, "layouts") {
return "go-html-template"
}
ext := extNoDelimiter(filename)
return chromaLexerFromType(ext)
}
func locateErrorInString(src string, matcher LineMatcherFn) *ErrorContext {
return locateError(strings.NewReader(src), &fileError{}, matcher)
}
func locateError(r io.Reader, le FileError, matches LineMatcherFn) *ErrorContext {
if le == nil {
panic("must provide an error")
}
ectx := &ErrorContext{LinesPos: -1, Position: text.Position{Offset: -1}}
b, err := io.ReadAll(r)
if err != nil {
return ectx
}
lines := strings.Split(string(b), "\n")
lineNo := 0
posBytes := 0
for li, line := range lines {
lineNo = li + 1
m := LineMatcher{
Position: le.Position(),
Error: le,
LineNumber: lineNo,
Offset: posBytes,
Line: line,
}
v := matches(m)
if ectx.LinesPos == -1 && v != -1 {
ectx.Position.LineNumber = lineNo
ectx.Position.ColumnNumber = v
break
}
posBytes += len(line)
}
if ectx.Position.LineNumber > 0 {
low := ectx.Position.LineNumber - 3
if low < 0 {
low = 0
}
if ectx.Position.LineNumber > 2 {
ectx.LinesPos = 2
} else {
ectx.LinesPos = ectx.Position.LineNumber - 1
}
high := ectx.Position.LineNumber + 2
if high > len(lines) {
high = len(lines)
}
ectx.Lines = lines[low:high]
}
return ectx
}