Enable more golang-ci linters (github#1149)

.golangci.yml

@@ -4,8 +4,21 @@ linters:
   disable:
     - errcheck
   enable:
+    - contextcheck
+    - durationcheck
+    - errname
+    - execinquery
+    - gofmt
+    - ifshort
+    - misspell
+    - nilerr
     - noctx
+    - nolintlint
+    - nosprintfhostport
+    - prealloc
     - rowserrcheck
     - sqlclosecheck
+    - unconvert
     - unused
-
+    - wastedassign
+    - whitespace

go/cmd/gh-ost/main.go

@@ -271,7 +271,7 @@ func main() {
 	}
 	if *askPass {
 		fmt.Println("Password:")
-		bytePassword, err := term.ReadPassword(int(syscall.Stdin))
+		bytePassword, err := term.ReadPassword(syscall.Stdin)
 		if err != nil {
 			migrationContext.Log.Fatale(err)
 		}
@@ -301,10 +301,9 @@ func main() {
 	acceptSignals(migrationContext)
 
 	migrator := logic.NewMigrator(migrationContext, AppVersion)
-	err := migrator.Migrate()
-	if err != nil {
+	if err := migrator.Migrate(); err != nil {
 		migrator.ExecOnFailureHook()
 		migrationContext.Log.Fatale(err)
 	}
-	fmt.Fprintf(os.Stdout, "# Done\n")
+	fmt.Fprintln(os.Stdout, "# Done")
 }

go/logic/applier.go

@@ -1034,7 +1034,6 @@ func (this *Applier) buildDMLEventQuery(dmlEvent *binlog.BinlogDMLEvent) (result
 
 // ApplyDMLEventQueries applies multiple DML queries onto the _ghost_ table
 func (this *Applier) ApplyDMLEventQueries(dmlEvents [](*binlog.BinlogDMLEvent)) error {
-
 	var totalDelta int64
 
 	err := func() error {

go/logic/migrator.go

@@ -979,7 +979,7 @@ func (this *Migrator) printStatus(rule PrintStatusRule, writers ...io.Writer) {
 		state = fmt.Sprintf("throttled, %s", throttleReason)
 	}
 
-	shouldPrintStatus := false
+	var shouldPrintStatus bool
 	if rule == HeuristicPrintStatusRule {
 		if elapsedSeconds <= 60 {
 			shouldPrintStatus = true
@@ -1298,7 +1298,7 @@ func (this *Migrator) executeWriteFuncs() error {
 						if niceRatio := this.migrationContext.GetNiceRatio(); niceRatio > 0 {
 							copyRowsDuration := time.Since(copyRowsStartTime)
 							sleepTimeNanosecondFloat64 := niceRatio * float64(copyRowsDuration.Nanoseconds())
-							sleepTime := time.Duration(time.Duration(int64(sleepTimeNanosecondFloat64)) * time.Nanosecond)
+							sleepTime := time.Duration(int64(sleepTimeNanosecondFloat64)) * time.Nanosecond
 							time.Sleep(sleepTime)
 						}
 					}

go/logic/server.go

@@ -1,5 +1,5 @@
 /*
-   Copyright 2021 GitHub Inc.
+   Copyright 2022 GitHub Inc.
 	 See https://github.com/github/gh-ost/blob/master/LICENSE
 */
 
@@ -122,8 +122,6 @@ func (this *Server) onServerCommand(command string, writer *bufio.Writer) (err e
 
 // applyServerCommand parses and executes commands by user
 func (this *Server) applyServerCommand(command string, writer *bufio.Writer) (printStatusRule PrintStatusRule, err error) {
-	printStatusRule = NoPrintStatusRule
-
 	tokens := strings.SplitN(command, "=", 2)
 	command = strings.TrimSpace(tokens[0])
 	arg := ""

go/logic/streamer.go

@@ -59,7 +59,6 @@ func NewEventsStreamer(migrationContext *base.MigrationContext) *EventsStreamer
 // AddListener registers a new listener for binlog events, on a per-table basis
 func (this *EventsStreamer) AddListener(
 	async bool, databaseName string, tableName string, onDmlEvent func(event *binlog.BinlogDMLEvent) error) (err error) {
-
 	this.listenersMutex.Lock()
 	defer this.listenersMutex.Unlock()
 

go/logic/throttler.go

@@ -180,7 +180,6 @@ func (this *Throttler) collectReplicationLag(firstThrottlingCollected chan<- boo
 
 // collectControlReplicasLag polls all the control replicas to get maximum lag value
 func (this *Throttler) collectControlReplicasLag() {
-
 	if atomic.LoadInt64(&this.migrationContext.HibernateUntil) > 0 {
 		return
 	}

go/mysql/instance_key.go

@@ -35,8 +35,7 @@ const detachHint = "//"
 
 // ParseInstanceKey will parse an InstanceKey from a string representation such as 127.0.0.1:3306
 func NewRawInstanceKey(hostPort string) (*InstanceKey, error) {
-	hostname := ""
-	port := ""
+	var hostname, port string
 	if submatch := ipv4HostPortRegexp.FindStringSubmatch(hostPort); len(submatch) > 0 {
 		hostname = submatch[1]
 		port = submatch[2]

go/sql/builder.go

@@ -167,7 +167,7 @@ func BuildRangeComparison(columns []string, values []string, args []interface{},
 	if includeEquals {
 		comparison, err := BuildEqualsComparison(columns, values)
 		if err != nil {
-			return "", explodedArgs, nil
+			return "", explodedArgs, err
 		}
 		comparisons = append(comparisons, comparison)
 		explodedArgs = append(explodedArgs, args...)

go/sql/parser.go

@@ -1,5 +1,5 @@
 /*
-   Copyright 2016 GitHub Inc.
+   Copyright 2022 GitHub Inc.
 	 See https://github.com/github/gh-ost/blob/master/LICENSE
 */
 
@@ -135,7 +135,6 @@ func (this *AlterTableParser) parseAlterToken(alterToken string) (err error) {
 }
 
 func (this *AlterTableParser) ParseAlterStatement(alterStatement string) (err error) {
-
 	this.alterStatementOptions = alterStatement
 	for _, alterTableRegexp := range alterTableExplicitSchemaTableRegexps {
 		if submatch := alterTableRegexp.FindStringSubmatch(this.alterStatementOptions); len(submatch) > 0 {