Merge pull request #147 from ec2-software/unwarp-error-list

Allow checking gqlerror.List for wrapped errors with `errors.Is` and `errors.As`

.circleci/config.yml

@@ -2,7 +2,7 @@ version: 2
 jobs:
   build:
     docker:
-      - image: golang:1.11
+      - image: golang:1.13
     working_directory: /gqlparser
     steps:
       - checkout

go.mod

@@ -1,6 +1,6 @@
 module github.com/vektah/gqlparser/v2
 
-go 1.12
+go 1.13
 
 require (
 	github.com/agnivade/levenshtein v1.0.1

gqlerror/error.go

@@ -2,6 +2,7 @@ package gqlerror
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"strconv"
 
@@ -80,6 +81,24 @@ func (errs List) Error() string {
 	return buf.String()
 }
 
+func (errs List) Is(target error) bool {
+	for _, err := range errs {
+		if errors.Is(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
+func (errs List) As(target interface{}) bool {
+	for _, err := range errs {
+		if errors.As(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
 func WrapPath(path ast.Path, err error) *Error {
 	return &Error{
 		err:     err,