github.com/uber/kraken@v0.1.4/utils/rwutil/cappedbuffer_test.go (about) 1 // Copyright (c) 2016-2019 Uber Technologies, Inc. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 package rwutil 15 16 import ( 17 "testing" 18 19 "bytes" 20 21 "github.com/stretchr/testify/require" 22 ) 23 24 func TestCappedBuffer_write_drain_success(t *testing.T) { 25 require := require.New(t) 26 27 content := []byte("hello this is a stream of bytes") 28 buffer := NewCappedBuffer(len(content)) 29 buffer.WriteAt(content[7:], 7) 30 buffer.WriteAt(content[:7], 0) 31 32 var dst bytes.Buffer 33 buffer.DrainInto(&dst) 34 require.Equal(content, dst.Bytes()) 35 } 36 37 func TestCappedBuffer_write_drain_error(t *testing.T) { 38 require := require.New(t) 39 40 content := []byte("hello this is a stream of bytes") 41 buffer := NewCappedBuffer(len(content) - 10) 42 _, err := buffer.WriteAt(content[7:], 7) 43 require.Error(err) 44 45 _, err = buffer.WriteAt(content[:7], 0) 46 require.NoError(err) 47 }