move function

src/textfile/collector.go

@@ -37,3 +37,7 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) {
 		c.collectFileErrors(ch)
 	}
 }
+
+func (c *Collector) appendErrorForPath(path string) {
+	c.fileMap[path].readErrors++
+}

src/textfile/writer.go

@@ -19,6 +19,3 @@ func (c *Collector) WriteTextFileMetrics(w http.ResponseWriter, r *http.Request)
 	}
 }
 
-func (c *Collector) appendErrorForPath(path string) {
-	c.fileMap[path].readErrors++
-}