www: do not obfuscate addresses in URLs

As they are likely Message-IDs.   If an email address ends up in
a URL, then it's likely public, so there's even less reason to
obfuscate that particular address.

[km: add xt/perf-obfuscate.t]
[ew: modernize perf test (5.10.1), use diag instead of print]

This version of the patch avoids the massive slowdown noted by Kyle in
<https://public-inbox.org/meta/87wnt9or6t.fsf@kyleam.com/>.
Performance remains roughly the same, if not slightly faster
(which may be due to me testing this on a busy server).  Results
from xt/perf-obfuscate.t against 6078 messages on a local mirror
of <https://public-inbox.org/meta/>:

	before: 6.67 usr + 0.04 sys = 6.71 CPU
	 after: 6.64 usr + 0.04 sys = 6.68 CPU

Reported-by: Kyle Meyer <kyle@kyleam.com>
Helped-by: Kyle Meyer <kyle@kyleam.com>
Link: https://public-inbox.org/meta/87a6q8p5qa.fsf@kyleam.com/

1 files changed, 4 insertions, 0 deletions

diff --git a/t/hval.t b/t/hval.t
index 9d0dab7a..5afc2052 100644
--- a/t/hval.t
+++ b/t/hval.t
@@ -47,6 +47,10 @@ EOF
 
 is($html, $exp, 'only obfuscated relevant addresses');
 
+$exp = 'https://example.net/foo@example.net';
+PublicInbox::Hval::obfuscate_addrs($ibx, my $res = $exp);
+is($res, $exp, 'does not obfuscate URL with Message-ID');
+
 is(PublicInbox::Hval::to_filename('foo bar  '), 'foo-bar',
         'to_filename has no trailing -');