Retain environment setting of "HOME" for tests that need os.path.expanduser()
to return a readable directory in the build chroot.

--- thefuck-3.25/tests/conftest.py
+++ thefuck-3.25/tests/conftest.py
@@ -64,6 +64,7 @@ def set_shell(monkeypatch):
 
 @pytest.fixture(autouse=True)
 def os_environ(monkeypatch):
-    env = {'PATH': os.environ['PATH']}
+    env = {'PATH': os.environ['PATH'],
+           'HOME': os.environ['HOME']}
     monkeypatch.setattr('os.environ', env)
     return env
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<tr><td><span title='2019-05-31 20:22:20 +0100'>2019-05-31</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=f6b0e1f8ff6a6459d7d39238ced165f4caa988fe'>services: Add getmail.</a><span class='msg-avail'>...</span></td><td>Christopher Baines</td></tr>
<tr><td><span title='2018-10-18 01:12:22 +0200'>2018-10-18</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=39d7fdce453b0ca23ecbed72048647debbaa58a6'>services: dhcp-client: Deprecate 'dhcp-client-service' procedure.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-06-13 09:11:45 +0200'>2018-06-13</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=c24b15472baaa7ec67d48cbf296bbe5ab727b78f'>tests: Honor the return value of 'start-service'.</a><span class='msg-avail'>...</span></td><td>Clément Lassieur</td></tr>
<tr><td><span title='2018-03-09 17:24:45 +0300'>2018-03-09</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=a9079b488037371f90514b82961dc075ea0b3985'>tests: mail: Add test for dovecot.</a><span class='msg-avail'>...</span></td><td>Oleg Pykhalov</td></tr>
<tr><td><span title='2017-07-20 11:57:13 +0200'>2017-07-20</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=8b113790fa3bfd2300c737901ba161f079fedbdf'>tests: Use 'virtual-machine' records instead of monadic procedures.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-04-19 23:43:50 +0200'>2017-04-19</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=950026ac7f17b3b4d5420cde9709c24e9af76dcb'>tests: mail: Add test for exim</a><span class='msg-avail'>...</span></td><td>Carlo Zancanaro</td></tr>
<tr><td><span title='2017-04-01 00:45:18 +0200'>2017-04-01</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=892d9089a88abaa2ef1127f16308d03f4f08a4ce'>tests: Introduce 'simple-operating-system' and use it.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-11-27 10:15:43 +0800'>2016-11-27</span></td><td><a href='/guix/commit/gnu/tests/mail.scm?id=a82f0b36177848eda340d880ae0802c3e26c4ea8'>tests: Add 'opensmtpd-service-type' test.</a><span class='msg-avail'>...</span></td><td>宋文武</td></tr>