The current version of File::Temp (0.2310) is failing tests consistently in blead and when downloaded from CPAN.
t/tempfile.t is failing for what I assume is related to running the tests as root on a linux system.
Output from a perl 5.30 run:
$>prove -wbvm t/tempfile.t
t/tempfile.t ..
1..30
ok 1 - Start test
ok 2 - Tempfile exists
ok 3 - Tempfile closed
ok 4 - Tempfile exists
# Template: tmpdirXXXXXX
# TEMPDIR: tmpdirsQAUeh
ok 5 - Local tempdir exists
# TEMPDIR2: customU984k
ok 6 - tempdir with TEMPLATE
# TEMPFILE: Created tmpdirsQAUeh/xzmCLuGZZy.dat
ok 7 - Local temp file exists with .dat extension
ok 8 - Local tempfile in tempdir exists
ok 9 - Created tempfile with default permissions
not ok 10 - Created tempfile with changed permissions
# Failed test 'Created tempfile with changed permissions'
# at t/tempfile.t line 126.
# TEMPFILE: Created tmpdirsQAUeh/V8j5pa6oaF
# TEMPFILE: Created tmpdirsQAUeh/hellokDhHot1.dat
ok 11 - Local tempfile in tempdir with .dat extension exists
# TEMPFILE: Created tmpdirsQAUeh/goodbyeVBdQB9T.dat
ok 12 - Local tempfile in tempdir with TEMPLATE
# TEMPFILE: Created permj9dWpGP
ok 13 - Long-lived temp file
ok 14 - Close long-lived temp file
ok 15 - Write to temp file
ok 16 - Close temp file
# TEMPDIR: /tmp/4eY4QqbN2j
ok 17 - Temp directory in temp dir
# End of tests. Execute END blocks in directory /tmp/4eY4QqbN2j
ok 18 - Dir /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh should not be present
ok 19 - Dir /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh should not be present
ok 20 - Dir /tmp/4eY4QqbN2j should not be present
ok 21 - File /tmp/NFgesclmBy.txt should not be present
ok 22 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/xzmCLuGZZy.dat should not be present
ok 23 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/ISD1GfL2El should not be present
ok 24 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/bVizVJXEWi should not be present
ok 25 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/V8j5pa6oaF should not be present
ok 26 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/hellokDhHot1.dat should not be present
ok 27 - File /root/.cpan/build/File-Temp-0.2310-0/tmpdirsQAUeh/goodbyeVBdQB9T.dat should not be present
ok 28 - File /root/.cpan/build/File-Temp-0.2310-0/permj9dWpGP is still present
ok 29 - Unlink file
ok 30 - File is no longer present
# Looks like you failed 1 test of 30.
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/30 subtests
Test Summary Report
-------------------
t/tempfile.t (Wstat: 256 Tests: 30 Failed: 1)
Failed test: 10
Non-zero exit status: 1
Files=1, Tests=30, 0 wallclock secs ( 0.04 usr 0.00 sys + 0.12 cusr 0.02 csys = 0.18 CPU)
Result: FAIL