Honor the 'SOURCE_DATE_EPOCH' environment variable to allow for
determinitic builds.

--- a/Lib/py_compile.py
+++ b/Lib/py_compile.py
@@ -105,7 +105,10 @@ def compile(file, cfile=None, dfile=None, doraise=False):
     """
     with open(file, 'U') as f:
         try:
-            timestamp = long(os.fstat(f.fileno()).st_mtime)
+            if 'SOURCE_DATE_EPOCH' in os.environ:
+                timestamp = long(os.environ['SOURCE_DATE_EPOCH'])
+            else:
+                timestamp = long(os.fstat(f.fileno()).st_mtime)
         except AttributeError:
             timestamp = long(os.stat(file).st_mtime)
         codestring = f.read()
diff --git a/Python/import.c b/Python/import.c
index e47ce63..7eecf9c 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -945,6 +945,11 @@ write_compiled_module(PyCodeObject *co, char *cpathname, struct stat *srcstat, t
     /* Now write the true mtime (as a 32-bit field) */
     fseek(fp, 4L, 0);
     assert(mtime <= 0xFFFFFFFF);
+    if (Py_GETENV("SOURCE_DATE_EPOCH") != NULL) {
+	const char *epoch = Py_GETENV("SOURCE_DATE_EPOCH");
+	mtime = atoi(epoch);
+    }
+
     PyMarshal_WriteLongToFile((long)mtime, fp, Py_MARSHAL_VERSION);
     fflush(fp);
     fclose(fp);
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<div class='path'>path: <a href='/guix/log/?id=fd9599f2b92263337f7821aad5669fd728d34da2'>root</a>/<a href='/guix/log/tests?id=fd9599f2b92263337f7821aad5669fd728d34da2'>tests</a>/<a href='/guix/log/tests/guix-refresh.sh?id=fd9599f2b92263337f7821aad5669fd728d34da2'>guix-refresh.sh</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/guix-refresh.sh?id=fd9599f2b92263337f7821aad5669fd728d34da2&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-08-15 09:38:29 -0400'>2023-08-15</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=2884abb3df4f95cef75219435ce9c1c968068568'>refresh: Add --target-version option.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/scripts/refresh.scm (%options): Register 'target-version' long version.
(update-specification-&gt;update-spec): Add a fallback-version argument.
(options-&gt;update-specs): Honor target-version option.
* tests/guix-refresh.sh: Test it.
* doc/guix.texi (Invoking guix refresh): Document it.

Reviewed-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-05-31 23:25:26 +0200'>2023-05-31</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=57ceb64e3464c347f42bd883e394163904f928ec'>upstream: Honor package properties for ignored and extra inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/upstream.scm (update-package-inputs)[filtered-inputs]
[regular-inputs, native-inputs, propagated-inputs]: New procedures.
Use them in 'update-field' calls.
* tests/guix-refresh.sh (GUIX_TEST_UPDATER_TARGETS): Add "libreoffice"
to the dependencies of "the-test-package".  Add 'updater-ignored-inputs'
property to "the-test-package".
* doc/guix.texi (Invoking guix refresh): Document it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-05-31 23:25:25 +0200'>2023-05-31</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=ec0a2fc87bd651ebc8f253f6369ba4485912d9b2'>upstream: 'update-package-source' edits input fields.</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, 'guix refresh r-ggplot2 -u' and similar commands would print
of list of input changes that would have to be made manually.  With this
change, 'guix refresh -u' takes care of updating input fields
automatically.

* guix/upstream.scm (update-package-inputs): New procedure.
(update-package-source): Call it when 'upstream-source-inputs' returns
true.
* guix/scripts/refresh.scm (update-package): Remove iteration over the
result of 'changed-inputs'.
* guix/import/test.scm (available-updates): Add support for input
lists.
* tests/guix-refresh.sh (GUIX_TEST_UPDATER_TARGETS): Add input list for
"the-test-package".
Make sure 'guix refresh -u' updates 'inputs' accordingly.
* doc/guix.texi (Invoking guix refresh): Mention it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-04-21 17:09:46 +0200'>2023-04-21</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=61a6b05850f99dcff65c83585c97604466d4ecf3'>tests: Relax two tests that expected a non-zero error code.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/guix-package-aliases.sh: "guix upgrade foo bar" has always
returned zero; adjust accordingly.
* tests/guix-refresh.sh: "guix refresh -t test idutils" and similar
return zero; adjust accordingly.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-04-21 16:16:38 +0200'>2023-04-21</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=37dd69b44511dc73eb04bdebe8d82c9a0386338e'>tests: Fix checks for expected failures.</a><span class='msg-avail'>...<span class='msg-tooltip'>Addresses &lt;https://issues.guix.gnu.org/62406&gt;.

With 'set -e', a return status inverted with '!' does not cause the shell to
exit immediately.  Instead use '&amp;&amp; false' to indicate an expected failure.

* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh,
tests/guix-environment-container.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-home.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh, tests/guix-refresh.sh, tests/guix-shell.sh,
tests/guix-style.sh, tests/guix-system.sh: Replace uses of '! ...' with
'... &amp;&amp; false' or `test ! ...` as appropriate.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2023-01-25 22:53:20 +0100'>2023-01-25</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=ebcb5c8e120b39a3dd07c27bc17d520ee653ec23'>tests: Do not try to create "$HOME/.config".</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously this test would fail when HOME=/homeless-shelter and said
directory cannot be created.

* tests/guix-refresh.sh: Pass '--keyring' together with '-u'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-01-08 16:11:45 +0100'>2023-01-08</span></td><td><a href='/guix/commit/tests/guix-refresh.sh?id=04f247be81dcb5296ecab776f735bb615a1039d3'>refresh: Add CLI tests.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/import/test.scm, tests/guix-refresh.sh: New files.
* Makefile.am (MODULES, SH_TESTS): Add them.
</span></span></td><td>Ludovic Courtès</td></tr>