fix: SetLogger via klog.SetLogger will output an unexpected newline

klog always adds a newline to the msg. klog will work fine without klog.

Set logr with klog.SetLogger, and klog will also pass the msg with the newline added to logr, which will result in an accidental newline being added.

step1: klog.Info("hello world")
step2: msg = msg + "\n"
step3: stdout.W(msg) or logr.Info(msg[:len(msg)-1])

fix #370

Signed-off-by: aimuz <mr.imuz@gmail.com>

klog.go

@@ -873,6 +873,9 @@ func (l *loggingT) output(s severity.Severity, logger *logWriter, buf *buffer.Bu
 		if logger.writeKlogBuffer != nil {
 			logger.writeKlogBuffer(data)
 		} else {
+			if data[len(data)-1] == '\n' {
+				data = data[:len(data)-1]
+			}
 			// TODO: set 'severity' and caller information as structured log info
 			// keysAndValues := []interface{}{"severity", severityName[s], "file", file, "line", line}
 			if s == severity.ErrorLog {

klog_test.go

@@ -1522,15 +1522,15 @@ func TestInfoSWithLogr(t *testing.T) {
 		keysValues: []interface{}{},
 		expected: testLogrEntry{
 			severity:      severity.InfoLog,
-			msg:           "foo",
+			msg:           "foo\n",
 			keysAndValues: []interface{}{},
 		},
 	}, {
 		msg:        "bar",
 		keysValues: []interface{}{"a", 1},
 		expected: testLogrEntry{
 			severity:      severity.InfoLog,
-			msg:           "bar",
+			msg:           "bar\n",
 			keysAndValues: []interface{}{"a", 1},
 		},
 	}}
@@ -1810,7 +1810,7 @@ func (l *testLogr) Info(level int, msg string, keysAndValues ...interface{}) {
 	defer l.mutex.Unlock()
 	l.entries = append(l.entries, testLogrEntry{
 		severity:      severity.InfoLog,
-		msg:           msg,
+		msg:           msg + "\n",
 		keysAndValues: keysAndValues,
 	})
 }