feat: fix possible line loss and duplication when file name is changed

.github/workflows/ci.yml

@@ -4,16 +4,16 @@ jobs:
   test-build:
     strategy:
       matrix:
-        go-version: [1.21.x, 1.20.x, 1.19.x, 1.18.x]
-        os: [ubuntu-20.04, macos-latest, windows-latest]
+        go-version: [1.26.x, 1.25.x]
+        os: [ubuntu-22.04, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
     - name: Install Go
-      uses: actions/setup-go@v2
+      uses: actions/setup-go@v4
       with:
         go-version: ${{ matrix.go-version }}
     - name: Checkout code
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
           fetch-depth: 0
     - name: Test

CHANGES.md

@@ -1,3 +1,6 @@
+# Unreleased
+* PR #1: possible line loss and duplication when file is renamed.
+
 # Version v1.4.11
 * Bump fsnotify to v1.6.0. Should fix some issues.
 

Dockerfile

@@ -1,17 +1,17 @@
 FROM golang
 
-RUN mkdir -p $GOPATH/src/github.com/nxadm/tail/
-ADD . $GOPATH/src/github.com/nxadm/tail/
+RUN mkdir -p $GOPATH/src/github.com/tarantool/go-tail/
+ADD . $GOPATH/src/github.com/tarantool/go-tail/
 
 # expecting to fetch dependencies successfully.
-RUN go get -v github.com/nxadm/tail
+RUN go get -v github.com/tarantool/go-tail
 
 # expecting to run the test successfully.
-RUN go test -v github.com/nxadm/tail
+RUN go test -v github.com/tarantool/go-tail
 
 # expecting to install successfully
-RUN go install -v github.com/nxadm/tail
-RUN go install -v github.com/nxadm/tail/cmd/gotail
+RUN go install -v github.com/tarantool/go-tail
+RUN go install -v github.com/tarantool/go-tail/cmd/gotail
 
 RUN $GOPATH/bin/gotail -h || true
 

README.md

@@ -1,9 +1,8 @@
-[![Go Reference](https://pkg.go.dev/badge/github.com/nxadm/tail.svg)](https://pkg.go.dev/github.com/nxadm/tail#section-documentation)
-![ci](https://github.com/nxadm/tail/workflows/ci/badge.svg)
-[![FreeBSD](https://api.cirrus-ci.com/github/nxadm/tail.svg)](https://cirrus-ci.com/github/nxadm/tail)
+[![Go Reference](https://pkg.go.dev/badge/github.com/tarantool/go-tail.svg)](https://pkg.go.dev/github.com/tarantool/go-tail#section-documentation)
+![ci](https://github.com/tarantool/go-tail/workflows/ci/badge.svg)
 # tail functionality in Go
 
-nxadm/tail provides a Go library that emulates the features of the BSD `tail`
+tarantool/go-tail provides a Go library that emulates the features of the BSD `tail`
 program. The library comes with full support for truncation/move detection as
 it is designed to work with log rotation tools. The library works on all
 operating systems supported by Go, including POSIX systems like Linux, *BSD,
@@ -25,11 +24,11 @@ for line := range t.Lines {
 }
 ```
 
-See [API documentation](https://pkg.go.dev/github.com/nxadm/tail#section-documentation).
+See [API documentation](https://pkg.go.dev/github.com/tarantool/go-tail#section-documentation).
 
 ## Installing
 
-    go get github.com/nxadm/tail/...
+    go get github.com/tarantool/go-tail/...
 
 ## History
 

cmd/gotail/gotail.go

@@ -1,3 +1,4 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/go-tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
 // Copyright (c) 2015 HPE Software Inc. All rights reserved.
 // Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
@@ -7,9 +8,10 @@ package main
 import (
 	"flag"
 	"fmt"
-    "io"
+	"io"
 	"os"
-	"github.com/nxadm/tail"
+
+	"github.com/tarantool/go-tail"
 )
 
 func args2config() (tail.Config, int64) {

examples/01-tailAndPrint/main.go

@@ -7,7 +7,7 @@ package main
 import (
 	"fmt"
 
-	"github.com/nxadm/tail"
+	"github.com/tarantool/go-tail"
 )
 
 var logFile = "/var/log/syslog"

examples/02-closeAndReopen/main.go

@@ -8,7 +8,7 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/nxadm/tail"
+	"github.com/tarantool/go-tail"
 )
 
 var logFile = "/var/log/syslog"

examples/03-consumeJSON/main.go

@@ -11,8 +11,8 @@ import (
 	"io/ioutil"
 	"os"
 	"strconv"
-	
-	"github.com/nxadm/tail"
+
+	"github.com/tarantool/go-tail"
 )
 
 type jsonStruct struct {
@@ -36,13 +36,13 @@ func main() {
 	go createJSON(file)
 	var js jsonStruct
 	for line := range t.Lines {
-		fmt.Printf("JSON: " + line.Text + "\n")
+		fmt.Println("JSON: " + line.Text)
 
 		err := json.Unmarshal([]byte(line.Text), &js)
 		if err != nil {
 			panic(err)
 		}
-		fmt.Printf("JSON counter field: " + js.Counter + "\n")
+		fmt.Println("JSON counter field: " + js.Counter)
 	}
 }
 

go.mod

@@ -1,8 +1,10 @@
-module github.com/nxadm/tail
+module github.com/tarantool/go-tail
 
-go 1.13
+go 1.25.7
 
 require (
 	github.com/fsnotify/fsnotify v1.6.0
 	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7
 )
+
+require golang.org/x/sys v0.0.0-20220908164124-27713097b956 // indirect

tail.go

@@ -1,12 +1,13 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/go-tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
 // Copyright (c) 2015 HPE Software Inc. All rights reserved.
 // Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
 
-//nxadm/tail provides a Go library that emulates the features of the BSD `tail`
-//program. The library comes with full support for truncation/move detection as
-//it is designed to work with log rotation tools. The library works on all
-//operating systems supported by Go, including POSIX systems like Linux and
-//*BSD, and MS Windows. Go 1.9 is the oldest compiler release supported.
+// tarantool/go-tail provides a Go library that emulates the features of the BSD `tail`
+// program. The library comes with full support for truncation/move detection as
+// it is designed to work with log rotation tools. The library works on all
+// operating systems supported by Go, including POSIX systems like Linux and
+// *BSD, and MS Windows. Go 1.9 is the oldest compiler release supported.
 package tail
 
 import (
@@ -21,10 +22,11 @@ import (
 	"sync"
 	"time"
 
-	"github.com/nxadm/tail/ratelimiter"
-	"github.com/nxadm/tail/util"
-	"github.com/nxadm/tail/watch"
 	"gopkg.in/tomb.v1"
+
+	"github.com/tarantool/go-tail/ratelimiter"
+	"github.com/tarantool/go-tail/util"
+	"github.com/tarantool/go-tail/watch"
 )
 
 var (
@@ -383,6 +385,13 @@ func (tail *Tail) waitForChanges() error {
 		}
 	}
 
+	// The write event should be handled first.
+	select {
+	case <-tail.changes.Modified:
+		return nil
+	default:
+	}
+
 	select {
 	case <-tail.changes.Modified:
 		return nil

tail_posix.go

@@ -1,4 +1,6 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/go-tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
+//go:build !windows
 // +build !windows
 
 package tail

tail_test.go

@@ -1,3 +1,4 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/go-tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
 // Copyright (c) 2015 HPE Software Inc. All rights reserved.
 // Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
@@ -17,8 +18,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/nxadm/tail/ratelimiter"
-	"github.com/nxadm/tail/watch"
+	"github.com/tarantool/go-tail/ratelimiter"
+	"github.com/tarantool/go-tail/watch"
 )
 
 func TestTailFile(t *testing.T) {

tail_windows.go

@@ -1,12 +1,14 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/go-tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
+//go:build windows
 // +build windows
 
 package tail
 
 import (
 	"os"
 
-	"github.com/nxadm/tail/winfile"
+	"github.com/tarantool/go-tail/winfile"
 )
 
 // Deprecated: this function is only useful internally and, as such,

util/util.go

@@ -1,3 +1,4 @@
+// Copyright (c) 2026 FOSS contributors of https://github.com/tarantool/tail
 // Copyright (c) 2019 FOSS contributors of https://github.com/nxadm/tail
 // Copyright (c) 2015 HPE Software Inc. All rights reserved.
 // Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
@@ -19,7 +20,7 @@ var LOGGER = &Logger{log.New(os.Stderr, "", log.LstdFlags)}
 
 // fatal is like panic except it displays only the current goroutine's stack.
 func Fatal(format string, v ...interface{}) {
-	// https://github.com/nxadm/log/blob/master/log.go#L45
+	// https://github.com/hpcloud/log/blob/master/log.go#L45
 	LOGGER.Output(2, fmt.Sprintf("FATAL -- "+format, v...)+"\n"+string(debug.Stack()))
 	os.Exit(1)
 }