I think it's Test::TCP that is broken on Windows. It relies on fork(), and I don't think that sockets and fork() play well under plain Win32. You seem to be using Cygwin, so maybe the problem lies elsewhere, but maybe the problems extend from plain Win32 to Cygwin as well.

My approach to debugging this would be to run the Test::TCP tests in isolation:

> cpanm --look Test::TCP
C:\...Test-TCP> perl Makefile.PL
C:\...Test-TCP> make test
C:\...Test-TCP> perl -Ilib t\test-that-hung-or-failed.t
... debug the test
C:\...Test-TCP> make install
[download]

I followed your instructions and here is the result:





perl Makefile.PL 
cp META.json MYMETA.json
cp META.yml MYMETA.yml
Checking if your kit is complete...
Looks good
Generating a Unix-style Makefile
Writing Makefile for Test::TCP
/home/user/.cpanm/work/1404793946.7456/Test-TCP-2.06[102]> make test
cp lib/Test/TCP/CheckPort.pm blib/lib/Test/TCP/CheckPort.pm
cp lib/Net/EmptyPort.pm blib/lib/Net/EmptyPort.pm
cp lib/Test/TCP.pm blib/lib/Test/TCP.pm
PERL_DL_NONLAZY=1 /usr/bin/perl.exe "-MExtUtils::Command::MM" "-MTest:
+:Harness" "-e" "undef *Test::Harness::Switches; test_harness(0, 'blib
+/lib', 'blib/arch')" t/*.t
t/00_compile.t ................. 1/1 # Test::More: 0.98
t/00_compile.t ................. ok   
t/01_simple.t .................. empty port not found at /home/user/.c
+panm/work/1404793946.7456/Test-TCP-2.06/blib/lib/Net/EmptyPort.pm lin
+e 37.
# Looks like your test exited with 255 before it could output anything
+.
t/01_simple.t .................. Dubious, test returned 255 (wstat 652
+80, 0xff00)
Failed 22/22 subtests 
t/02_abrt.t .................... empty port not found at /home/user/.c
+panm/work/1404793946.7456/Test-TCP-2.06/blib/lib/Net/EmptyPort.pm lin
+e 37.
# Looks like your test exited with 255 before it could output anything
+.
t/02_abrt.t .................... Dubious, test returned 255 (wstat 652
+80, 0xff00)
Failed 2/2 subtests 
t/03_return_when_sigterm.t ..... empty port not found at /home/user/.c
+panm/work/1404793946.7456/Test-TCP-2.06/blib/lib/Net/EmptyPort.pm lin
+e 37.
# Looks like your test exited with 255 before it could output anything
+.
t/03_return_when_sigterm.t ..... Dubious, test returned 255 (wstat 652
+80, 0xff00)
Failed 2/2 subtests 
t/04_die.t ..................... 1/3 
#   Failed test at t/04_die.t line 25.
#                   'empty port not found at /home/user/.cpanm/work/14
+04793946.7456/Test-TCP-2.06/blib/lib/Net/EmptyPort.pm line 37.
# '
#     doesn't match '(?^:sinamon)'
Can't kill a non-numeric process ID at t/04_die.t line 26.
# Looks like you planned 3 tests but ran 2.
# Looks like you failed 1 test of 2 run.
# Looks like your test exited with 255 just after 2.
t/04_die.t ..................... Dubious, test returned 255 (wstat 652
+80, 0xff00)
Failed 2/3 subtests 
t/05_sigint.t .................. 1/2 # $Config{sig_name}: ZERO HUP INT
+ QUIT ILL TRAP ABRT EMT FPE KILL BUS SEGV SYS PIPE ALRM TERM URG STOP
+ TSTP CONT CHLD TTIN TTOU IO XCPU XFSZ VTALRM PROF WINCH LOST USR1 US
+R2 RTMAX CLD POLL PWR RTMIN 
# CHILD_ERROR_NATIVE: 2
# $?: 2
t/05_sigint.t .................. ok   
t/06_nest.t .................... empty port not found at /home/user/.c
+panm/work/1404793946.7456/Test-TCP-2.06/blib/lib/Net/EmptyPort.pm lin
+e 37.
# Looks like your test exited with 255 before it could output anything
+.
t/06_nest.t .................... Dubious, test returned 255 (wstat 652
+80, 0xff00)
Failed 1/1 subtests 
t/07_optional.t ................ ok   
t/08_exit.t ....................
[download]





I'm seeing a lot of "empty port not found" messages. Do you know what the problem could be?

I'm seeing a lot of "empty port not found" messages. Do you know what the problem could be?

Maybe you have some kind of firewall running? Maybe you need to run this test as root due to too-low port number or some such :/

See also Failing tests of Test::TCP on Windows

I read that thread and the other links it contains, but all I see is an acknowledgement of problems with no official solutions. Or did I miss something?

Let me ask a different question: I have had problems installing perl modules from CPAN before, and occasionally the "solution" is to do a force install because the test itself is either broken or isn't testing for something that really matters in the context in which the module is used. Could that be the case here? If I force install Test::TCP given my current build failures will WWW::Mechanize::PhantomJS still work?

Test::TCP is a module for testing TCP connections. WWW::Mechanize::PhantomJS does not use Test::TCP, so the two are not interrelated. I think Test::TCP is pulled in by LWP::Protocol::PSGI for self-testing.

There may be problems with your setup that prevent Test::TCP from passing its test suite that may also prevent WWW::Mechanize::PhantomJS from working, but they are not apparent to me.