Revert "testing/fstest: test that ReadDirFile on a non-dir fails"

This reverts commit 1853411d8376570295711f9084d494d458822578.

Reason for revert: broke plan 9 builder. fixes #44967

Change-Id: Ib89448d37f7ab8bb05dbd89ce744431d807eb4da
Reviewed-on: https://go-review.googlesource.com/c/go/+/301190
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>

1 files changed, 0 insertions, 9 deletions

diff --git a/src/testing/fstest/testfs.go b/src/testing/fstest/testfs.go
index 27c603167f..e0ad60a17b 100644
--- a/src/testing/fstest/testfs.go
+++ b/src/testing/fstest/testfs.go
@@ -119,9 +119,6 @@ func (t *fsTester) openDir(dir string) fs.ReadDirFile {
 		t.errorf("%s: Open: %v", dir, err)
 		return nil
 	}
-	// It'd be nice to test here that f.Read fails, because f is a directory.
-	// However, FreeBSD supports calling read on a directory.
-	// See https://groups.google.com/g/golang-dev/c/rh8jwxyG1PQ.
 	d, ok := f.(fs.ReadDirFile)
 	if !ok {
 		f.Close()
@@ -517,12 +514,6 @@ func (t *fsTester) checkFile(file string) {
 		return
 	}
 
-	if dir, ok := f.(fs.ReadDirFile); ok {
-		if _, err := dir.ReadDir(-1); err == nil {
-			t.errorf("%s: ReadDir of non-dir file should return an error", file)
-		}
-	}
-
 	data, err := ioutil.ReadAll(f)
 	if err != nil {
 		f.Close()