tree 703f9640ab46cb879bddd951e253555af602e596
parent be7544be237b279e45be73963e84ab59916b8ac2
author Dan Peterson <dpiddy@gmail.com> 1447961082 -0400
committer Russ Cox <rsc@golang.org> 1450365426 +0000

net: prefer error for original name on lookups

With certain names and search domain configurations the
returned error would be one encountered while querying a
generated name instead of the original name. This caused
confusion when a manual check of the same name produced
different results.

Now prefer errors encountered for the original name.

Also makes the low-level DNS connection plumbing swappable
in tests enabling tighter control over responses without
relying on the network.

Fixes #12712
Updates #13295

Change-Id: I780d628a762006bb11899caf20b5f97b462a717f
Reviewed-on: https://go-review.googlesource.com/16953
Reviewed-by: Russ Cox <rsc@golang.org>