gopls: use fmt.Fprintf

Change-Id: Ife7f3269df554d2ecb6d1ccf6d1c1fa6de49587c
GitHub-Last-Rev: 9faefaefc2cc344859edeb2912cc60e9f2be4850
GitHub-Pull-Request: golang/tools#406
Reviewed-on: https://go-review.googlesource.com/c/tools/+/438537
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
diff --git a/gopls/doc/generate.go b/gopls/doc/generate.go
index 449751e..9ab2d01 100644
--- a/gopls/doc/generate.go
+++ b/gopls/doc/generate.go
@@ -621,7 +621,7 @@
 			writeTitle(section, h.final, level)
 			for _, opt := range h.options {
 				header := strMultiply("#", level+1)
-				section.Write([]byte(fmt.Sprintf("%s ", header)))
+				fmt.Fprintf(section, "%s ", header)
 				opt.Write(section)
 			}
 		}
diff --git a/gopls/internal/hooks/diff.go b/gopls/internal/hooks/diff.go
index 01a37ae..46faae1 100644
--- a/gopls/internal/hooks/diff.go
+++ b/gopls/internal/hooks/diff.go
@@ -113,7 +113,7 @@
 	fname := fmt.Sprintf("%s/gopls-failed-%x", os.TempDir(), os.Getpid())
 	fd, err := os.Create(fname)
 	defer fd.Close()
-	_, err = fd.Write([]byte(fmt.Sprintf("%s\n%s\n", string(first), string(second))))
+	_, err = fmt.Fprintf(fd, "%s\n%s\n", first, second)
 	if err != nil {
 		// what do we tell the user?
 		return ""