hugo/common/herrors/file_error.go

107 lines
2.8 KiB
Go
Raw Normal View History

// Copyright 2018 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
// limitatio ns under the License.
package herrors
var _ causer = (*fileError)(nil)
// FileError represents an error when handling a file: Parsing a config file,
// execute a template etc.
type FileError interface {
error
// LineNumber gets the error location, starting at line 1.
LineNumber() int
ColumnNumber() int
// A string identifying the type of file, e.g. JSON, TOML, markdown etc.
Type() string
}
var _ FileError = (*fileError)(nil)
type fileError struct {
lineNumber int
columnNumber int
fileType string
cause error
}
func (e *fileError) LineNumber() int {
return e.lineNumber
}
func (e *fileError) ColumnNumber() int {
return e.columnNumber
}
func (e *fileError) Type() string {
return e.fileType
}
func (e *fileError) Error() string {
if e.cause == nil {
return ""
}
return e.cause.Error()
}
func (f *fileError) Cause() error {
return f.cause
}
// NewFileError creates a new FileError.
func NewFileError(fileType string, lineNumber, columnNumber int, err error) FileError {
return &fileError{cause: err, fileType: fileType, lineNumber: lineNumber, columnNumber: columnNumber}
}
// UnwrapFileError tries to unwrap a FileError from err.
// It returns nil if this is not possible.
func UnwrapFileError(err error) FileError {
for err != nil {
switch v := err.(type) {
case FileError:
return v
case causer:
err = v.Cause()
default:
return nil
}
}
return nil
}
// ToFileError will try to convert the given error to an error supporting
// the FileError interface.
// If will fall back to returning the original error if a line number cannot be extracted.
func ToFileError(fileType string, err error) error {
return ToFileErrorWithOffset(fileType, err, 0)
}
// ToFileErrorWithOffset will try to convert the given error to an error supporting
// the FileError interface. It will take any line number offset given into account.
// If will fall back to returning the original error if a line number cannot be extracted.
func ToFileErrorWithOffset(fileType string, err error, offset int) error {
for _, handle := range lineNumberExtractors {
lno, col := handle(err)
if lno > 0 {
return NewFileError(fileType, lno+offset, col, err)
}
}
// Fall back to the original.
return err
}