mirror of
https://github.com/dolthub/dolt.git
synced 2026-01-20 19:00:20 -06:00
101 lines
2.6 KiB
Go
101 lines
2.6 KiB
Go
// Copyright 2019 Dolthub, Inc.
|
|
//
|
|
// 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 test
|
|
|
|
import (
|
|
"io"
|
|
"math"
|
|
|
|
"github.com/google/uuid"
|
|
)
|
|
|
|
// TestError is an error that stores a uniquely generated id
|
|
type TestError struct {
|
|
ErrId uuid.UUID
|
|
}
|
|
|
|
// NewTestError creates a TestError with a newly created id
|
|
func NewTestError() *TestError {
|
|
id, _ := uuid.NewRandom()
|
|
return &TestError{id}
|
|
}
|
|
|
|
// Error is the only method defined in the error interface
|
|
func (te *TestError) Error() string {
|
|
return "Error! Error! Error!"
|
|
}
|
|
|
|
// TestReader is an io.Reader that will error after some number of bytes have been read
|
|
type TestReader struct {
|
|
data []byte
|
|
errorAfter int
|
|
totalRead int
|
|
}
|
|
|
|
// NewTestReader takes a size, and the number of bytes that should be read before the
|
|
// reader errors. The size is used to generate a buffer of random data that will be
|
|
// read by the caller. After the caller has read the specified number of bytes the
|
|
// call to read will fail.
|
|
func NewTestReader(dataSize, errorAfter int) *TestReader {
|
|
data := make([]byte, dataSize)
|
|
for i := 0; i < dataSize; i++ {
|
|
data[i] = byte(i % 256)
|
|
}
|
|
|
|
return NewTestReaderWithData(data, errorAfter)
|
|
}
|
|
|
|
// NewTestReaderWithData creates a TestReader with user supplied data and the number
|
|
// of bytes that can be read before errors start occurring on Read calls.
|
|
func NewTestReaderWithData(data []byte, errorAfter int) *TestReader {
|
|
return &TestReader{data, errorAfter, 0}
|
|
}
|
|
|
|
// Read reads data from the internal buffer
|
|
func (tr *TestReader) Read(p []byte) (int, error) {
|
|
dataRemaining := len(tr.data) - tr.totalRead
|
|
|
|
if dataRemaining == 0 {
|
|
return 0, io.EOF
|
|
}
|
|
|
|
remainingBeforeErr := math.MaxInt32
|
|
if tr.errorAfter != -1 {
|
|
remainingBeforeErr = tr.errorAfter - tr.totalRead
|
|
}
|
|
|
|
toRead := dataRemaining
|
|
if dataRemaining > remainingBeforeErr {
|
|
toRead = remainingBeforeErr
|
|
}
|
|
|
|
if toRead > len(p) {
|
|
toRead = len(p)
|
|
}
|
|
|
|
var copied int
|
|
if toRead > 0 {
|
|
copied = copy(p[:toRead], tr.data[tr.totalRead:tr.totalRead+toRead])
|
|
tr.totalRead += copied
|
|
}
|
|
|
|
var err error
|
|
if tr.totalRead == tr.errorAfter && copied != len(p) {
|
|
err = NewTestError()
|
|
}
|
|
|
|
return copied, err
|
|
}
|