github.com/waynz0r/controller-tools@v0.4.1-0.20200916220028-16254aeef2d7/pkg/loader/errors.go (about)

     1  /*
     2  Copyright 2019 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package loader
    18  
    19  import (
    20  	"fmt"
    21  	"go/ast"
    22  	"go/token"
    23  )
    24  
    25  // PositionedError represents some error with an associated position.
    26  // The position is tied to some external token.FileSet.
    27  type PositionedError struct {
    28  	Pos token.Pos
    29  	error
    30  }
    31  
    32  // ErrFromNode returns the given error, with additional information
    33  // attaching it to the given AST node.  It will automatically map
    34  // over error lists.
    35  func ErrFromNode(err error, node ast.Node) error {
    36  	if asList, isList := err.(ErrList); isList {
    37  		resList := make(ErrList, len(asList))
    38  		for i, baseErr := range asList {
    39  			resList[i] = ErrFromNode(baseErr, node)
    40  		}
    41  		return resList
    42  	}
    43  	return PositionedError{
    44  		Pos:   node.Pos(),
    45  		error: err,
    46  	}
    47  }
    48  
    49  // MaybeErrList constructs an ErrList if the given list of
    50  // errors has any errors, otherwise returning nil.
    51  func MaybeErrList(errs []error) error {
    52  	if len(errs) == 0 {
    53  		return nil
    54  	}
    55  	return ErrList(errs)
    56  }
    57  
    58  // ErrList is a list of errors aggregated together into a single error.
    59  type ErrList []error
    60  
    61  func (l ErrList) Error() string {
    62  	return fmt.Sprintf("%v", []error(l))
    63  }