added .Unwrap()error methods, and some error checking

badgateway.go

@@ -5,6 +5,8 @@ type BadGateway interface {
 	BadGateway()
 }
 
+var _ BadGateway = internalBadGateway{}
+
 type internalBadGateway struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalBadGateway) ServerError() {
 func (internalBadGateway) BadGateway() {
 	// Nothing here.
 }
+
+func (receiver internalBadGateway) Unwrap() error {
+	return receiver.err
+}

badrequest.go

@@ -30,3 +30,7 @@ func (internalBadRequest) ClientError() {
 func (internalBadRequest) BadRequest() {
 	// Nothing here.
 }
+
+func (receiver internalBadRequest) Unwrap() error {
+	return receiver.err
+}

conflict.go

@@ -30,3 +30,7 @@ func (internalConflict) ClientError() {
 func (internalConflict) Conflict() {
 	// Nothing here.
 }
+
+func (receiver internalConflict) Unwrap() error {
+	return receiver.err
+}

error.go

@@ -3,4 +3,5 @@ package errhttp
 type Error interface {
 	error
 	Err() error
+	Unwrap() error
 }

expectationfailed.go

@@ -30,3 +30,7 @@ func (internalExpectationFailed) ClientError() {
 func (internalExpectationFailed) ExpectationFailed() {
 	// Nothing here.
 }
+
+func (receiver internalExpectationFailed) Unwrap() error {
+	return receiver.err
+}

faileddependency.go

@@ -31,3 +31,6 @@ func (internalFailedDependency) FailedDependency() {
 	// Nothing here.
 }
 
+func (receiver internalFailedDependency) Unwrap() error {
+	return receiver.err
+}

forbidden.go

@@ -31,3 +31,6 @@ func (internalForbidden) Forbidden() {
 	// Nothing here.
 }
 
+func (receiver internalForbidden) Unwrap() error {
+	return receiver.err
+}

gatewaytimeout.go

@@ -5,6 +5,8 @@ type GatewayTimeout interface {
 	GatewayTimeout()
 }
 
+var _ GatewayTimeout = internalGatewayTimeout{}
+
 type internalGatewayTimeout struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalGatewayTimeout) ServerError() {
 func (internalGatewayTimeout) GatewayTimeout() {
 	// Nothing here.
 }
+
+func (receiver internalGatewayTimeout) Unwrap() error {
+	return receiver.err
+}

gone.go

@@ -31,3 +31,6 @@ func (internalGone) Gone() {
 	// Nothing here.
 }
 
+func (receiver internalGone) Unwrap() error {
+	return receiver.err
+}

httpversionnotsupported.go

@@ -5,6 +5,8 @@ type HTTPVersionNotSupported interface {
 	HTTPVersionNotSupported()
 }
 
+var _ HTTPVersionNotSupported = internalHTTPVersionNotSupported{}
+
 type internalHTTPVersionNotSupported struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalHTTPVersionNotSupported) ServerError() {
 func (internalHTTPVersionNotSupported) HTTPVersionNotSupported() {
 	// Nothing here.
 }
+
+func (receiver internalHTTPVersionNotSupported) Unwrap() error {
+	return receiver.err
+}

insufficientstorage.go

@@ -5,6 +5,8 @@ type InsufficientStorage interface {
 	InsufficientStorage()
 }
 
+var _ InsufficientStorage = internalInsufficientStorage{}
+
 type internalInsufficientStorage struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalInsufficientStorage) ServerError() {
 func (internalInsufficientStorage) InsufficientStorage() {
 	// Nothing here.
 }
+
+func (receiver internalInsufficientStorage) Unwrap() error {
+	return receiver.err
+}

internalservererror.go

@@ -5,6 +5,8 @@ type InternalServerError interface {
 	InternalServerError()
 }
 
+var _ InternalServerError = internalInternalServerError{}
+
 type internalInternalServerError struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalInternalServerError) ServerError() {
 func (internalInternalServerError) InternalServerError() {
 	// Nothing here.
 }
+
+func (receiver internalInternalServerError) Unwrap() error {
+	return receiver.err
+}

lengthrequired.go

@@ -31,3 +31,6 @@ func (internalLengthRequired) LengthRequired() {
 	// Nothing here.
 }
 
+func (receiver internalLengthRequired) Unwrap() error {
+	return receiver.err
+}

locked.go

@@ -30,3 +30,7 @@ func (internalLocked) ClientError() {
 func (internalLocked) Locked() {
 	// Nothing here.
 }
+
+func (receiver internalLocked) Unwrap() error {
+	return receiver.err
+}

loopdetected.go

@@ -5,6 +5,8 @@ type LoopDetected interface {
 	LoopDetected()
 }
 
+var _ LoopDetected = internalLoopDetected{}
+
 type internalLoopDetected struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalLoopDetected) ServerError() {
 func (internalLoopDetected) LoopDetected() {
 	// Nothing here.
 }
+
+func (receiver internalLoopDetected) Unwrap() error {
+	return receiver.err
+}

methodnotallowed.go

@@ -31,3 +31,6 @@ func (internalMethodNotAllowed) MethodNotAllowed() {
 	// Nothing here.
 }
 
+func (receiver internalMethodNotAllowed) Unwrap() error {
+	return receiver.err
+}

networkauthenticationrequired.go

@@ -5,6 +5,8 @@ type NetworkAuthenticationRequired interface {
 	NetworkAuthenticationRequired()
 }
 
+var _ NetworkAuthenticationRequired = internalNetworkAuthenticationRequired{}
+
 type internalNetworkAuthenticationRequired struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalNetworkAuthenticationRequired) ServerError() {
 func (internalNetworkAuthenticationRequired) NetworkAuthenticationRequired() {
 	// Nothing here.
 }
+
+func (receiver internalNetworkAuthenticationRequired) Unwrap() error {
+	return receiver.err
+}

notacceptable.go

@@ -30,3 +30,7 @@ func (internalNotAcceptable) ClientError() {
 func (internalNotAcceptable) NotAcceptable() {
 	// Nothing here.
 }
+
+func (receiver internalNotAcceptable) Unwrap() error {
+	return receiver.err
+}

notextended.go

@@ -5,6 +5,8 @@ type NotExtended interface {
 	NotExtended()
 }
 
+var _ NotExtended = internalNotExtended{}
+
 type internalNotExtended struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalNotExtended) ServerError() {
 func (internalNotExtended) NotExtended() {
 	// Nothing here.
 }
+
+func (receiver internalNotExtended) Unwrap() error {
+	return receiver.err
+}

notfound.go

@@ -30,3 +30,7 @@ func (internalNotFound ) ClientError() {
 func (internalNotFound ) NotFound() {
 	// Nothing here.
 }
+
+func (receiver internalNotFound) Unwrap() error {
+	return receiver.err
+}

notimplemented.go

@@ -5,6 +5,8 @@ type NotImplemented interface {
 	NotImplemented()
 }
 
+var _ NotImplemented = internalNotImplemented{}
+
 type internalNotImplemented struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalNotImplemented) ServerError() {
 func (internalNotImplemented) NotImplemented() {
 	// Nothing here.
 }
+
+func (receiver internalNotImplemented) Unwrap() error {
+	return receiver.err
+}

payloadtoolarge.go

@@ -30,3 +30,7 @@ func (internalPayloadTooLarge) ClientError() {
 func (internalPayloadTooLarge) PayloadTooLarge() {
 	// Nothing here.
 }
+
+func (receiver internalPayloadTooLarge) Unwrap() error {
+	return receiver.err
+}

paymentrequired.go

@@ -30,3 +30,7 @@ func (internalPaymentRequired) ClientError() {
 func (internalPaymentRequired) PaymentRequired() {
 	// Nothing here.
 }
+
+func (receiver internalPaymentRequired) Unwrap() error {
+	return receiver.err
+}

preconditionfailed.go

@@ -30,3 +30,7 @@ func (internalPreconditionFailed) ClientError() {
 func (internalPreconditionFailed) PreconditionFailed() {
 	// Nothing here.
 }
+
+func (receiver internalPreconditionFailed) Unwrap() error {
+	return receiver.err
+}

preconditionrequired.go

@@ -31,3 +31,6 @@ func (internalPreconditionRequired) PreconditionRequired() {
 	// Nothing here.
 }
 
+func (receiver internalPreconditionRequired) Unwrap() error {
+	return receiver.err
+}

proxyauthrequired.go

@@ -30,3 +30,7 @@ func (internalProxyAuthRequired) ClientError() {
 func (internalProxyAuthRequired) ProxyAuthRequired() {
 	// Nothing here.
 }
+
+func (receiver internalProxyAuthRequired) Unwrap() error {
+	return receiver.err
+}

requestedrangenotsatisfiable.go

@@ -30,3 +30,7 @@ func (internalRequestedRangeNotSatisfiable) ClientError() {
 func (internalRequestedRangeNotSatisfiable) RequestedRangeNotSatisfiable() {
 	// Nothing here.
 }
+
+func (receiver internalRequestedRangeNotSatisfiable) Unwrap() error {
+	return receiver.err
+}

requestentitytoolarge.go

@@ -30,3 +30,7 @@ func (internalRequestEntityTooLarge) ClientError() {
 func (internalRequestEntityTooLarge) RequestEntityTooLarge() {
 	// Nothing here.
 }
+
+func (receiver internalRequestEntityTooLarge) Unwrap() error {
+	return receiver.err
+}

requestheaderfieldstoolarge.go

@@ -31,3 +31,7 @@ func (internalRequestHeaderFieldsTooLarge) ClientError() {
 func (internalRequestHeaderFieldsTooLarge) RequestHeaderFieldsTooLarge() {
 	// Nothing here.
 }
+
+func (receiver internalRequestHeaderFieldsTooLarge) Unwrap() error {
+	return receiver.err
+}

requesttimeout.go

@@ -31,3 +31,7 @@ func (internalRequestTimeout) ClientError() {
 func (internalRequestTimeout) RequestTimeout() {
 	// Nothing here.
 }
+
+func (receiver internalRequestTimeout) Unwrap() error {
+	return receiver.err
+}

requesturitoolong.go

@@ -31,3 +31,7 @@ func (internalRequestURITooLong) ClientError() {
 func (internalRequestURITooLong) RequestURITooLong() {
 	// Nothing here.
 }
+
+func (receiver internalRequestURITooLong) Unwrap() error {
+	return receiver.err
+}

serviceunavailable.go

@@ -30,3 +30,7 @@ func (internalServiceUnavailable) ServerError() {
 func (internalServiceUnavailable) ServiceUnavailable() {
 	// Nothing here.
 }
+
+func (receiver internalServiceUnavailable) Unwrap() error {
+	return receiver.err
+}

teapot.go

@@ -30,3 +30,7 @@ func (internalTeapot) ClientError() {
 func (internalTeapot) Teapot() {
 	// Nothing here.
 }
+
+func (receiver internalTeapot) Unwrap() error {
+	return receiver.err
+}

toomanyrequests.go

@@ -30,3 +30,7 @@ func (internalTooManyRequests) ClientError() {
 func (internalTooManyRequests) TooManyRequests() {
 	// Nothing here.
 }
+
+func (receiver internalTooManyRequests) Unwrap() error {
+	return receiver.err
+}

unauthorized.go

@@ -30,3 +30,7 @@ func (internalUnauthorized) ClientError() {
 func (internalUnauthorized) Unauthorized() {
 	// Nothing here.
 }
+
+func (receiver internalUnauthorized) Unwrap() error {
+	return receiver.err
+}

unavailableforlegalreasons.go

@@ -31,3 +31,6 @@ func (internalUnavailableForLegalReasons) UnavailableForLegalReasons() {
 	// Nothing here.
 }
 
+func (receiver internalUnavailableForLegalReasons) Unwrap() error {
+	return receiver.err
+}

unprocessableentity.go

@@ -30,3 +30,7 @@ func (internalUnprocessableEntity) ClientError() {
 func (internalUnprocessableEntity) UnprocessableEntity() {
 	// Nothing here.
 }
+
+func (receiver internalUnprocessableEntity) Unwrap() error {
+	return receiver.err
+}

unsupportedmediatype.go

@@ -30,3 +30,7 @@ func (internalUnsupportedMediaType) ClientError() {
 func (internalUnsupportedMediaType) UnsupportedMediaType() {
 	// Nothing here.
 }
+
+func (receiver internalUnsupportedMediaType) Unwrap() error {
+	return receiver.err
+}

upgraderequired.go

@@ -30,3 +30,7 @@ func (internalUpgradeRequired) ClientError() {
 func (internalUpgradeRequired) UpgradeRequired() {
 	// Nothing here.
 }
+
+func (receiver internalUpgradeRequired) Unwrap() error {
+	return receiver.err
+}

uritoolong.go

@@ -30,3 +30,7 @@ func (internalURITooLong) ClientError() {
 func (internalURITooLong) URITooLong() {
 	// Nothing here.
 }
+
+func (receiver internalURITooLong) Unwrap() error {
+	return receiver.err
+}

variantaisonegotiates.go

@@ -5,6 +5,8 @@ type VariantAlsoNegotiates interface {
 	VariantAlsoNegotiates()
 }
 
+var _ VariantAlsoNegotiates = internalVariantAlsoNegotiates{}
+
 type internalVariantAlsoNegotiates struct {
 	err error
 }
@@ -30,3 +32,7 @@ func (internalVariantAlsoNegotiates) ServerError() {
 func (internalVariantAlsoNegotiates) VariantAlsoNegotiates() {
 	// Nothing here.
 }
+
+func (receiver internalVariantAlsoNegotiates) Unwrap() error {
+	return receiver.err
+}