Merge pull request #116 from hashicorp/f-no-colon

Omit empty colon when message is empty. Fixes #109

intlogger.go

@@ -269,11 +269,14 @@ func (l *intLogger) logPlain(t time.Time, name string, level Level, msg string,
 
 	if name != "" {
 		l.writer.WriteString(name)
-		l.writer.WriteString(": ")
+		if msg != "" {
+			l.writer.WriteString(": ")
+			l.writer.WriteString(msg)
+		}
+	} else if msg != "" {
+		l.writer.WriteString(msg)
 	}
 
-	l.writer.WriteString(msg)
-
 	args = append(l.implied, args...)
 
 	var stacktrace CapturedStacktrace

logger_test.go

@@ -1004,6 +1004,24 @@ func TestLogger_JSON(t *testing.T) {
 		assert.Equal(t, "this is test", raw["@message"])
 		assert.Equal(t, errJsonUnsupportedTypeMsg, raw["@warn"])
 	})
+
+	t.Run("omits the entry for the message when empty", func(t *testing.T) {
+		var buf bytes.Buffer
+		DefaultOutput = &buf
+
+		logger := New(&LoggerOptions{
+			Name: "test",
+		})
+
+		logger.Info("", "who", "programmer", "why", "testing")
+
+		str := buf.String()
+		dataIdx := strings.IndexByte(str, ' ')
+		rest := str[dataIdx+1:]
+
+		assert.Equal(t, "[INFO]  test: who=programmer why=testing\n", rest)
+	})
+
 }
 
 type customErrJSON struct {