From 2c096b513273a758b446405d9e5efe4860af1036 Mon Sep 17 00:00:00 2001
From: Elvis Pranskevichus <elvis@magic.io>
Date: Thu, 27 Sep 2018 13:05:14 -0400
Subject: [PATCH] bpo-34022: Stop forcing of hash-based invalidation with
 SOURCE_DATE_EPOCH

Unconditional forcing of ``CHECKED_HASH`` invalidation was introduced in
3.7.0 in bpo-29708.  The change is bad, as it unconditionally overrides
*invalidation_mode*, even if it was passed as an explicit argument to
``py_compile.compile()`` or ``compileall``.  An environment variable
should *never* override an explicit argument to a library function.
That change leads to multiple test failures if the ``SOURCE_DATE_EPOCH``
environment variable is set.

This changes ``py_compile.compile()`` to only look at
``SOURCE_DATE_EPOCH`` if no explicit *invalidation_mode* was specified.
I also made various relevant tests run with explicit control over the
value of ``SOURCE_DATE_EPOCH``.

While looking at this, I noticed that ``zipimport`` does not work
with hash-based .pycs _at all_, though I left the fixes for
subsequent commits.
---
 Doc/library/compileall.rst                    | 11 ++--
 Doc/library/py_compile.rst                    | 13 ++--
 Lib/compileall.py                             | 20 ++++--
 Lib/py_compile.py                             | 13 +++-
 Lib/test/test_compileall.py                   | 50 ++++++++++++--
 .../test_importlib/source/test_file_loader.py | 15 +++++
 Lib/test/test_py_compile.py                   | 66 +++++++++++++++++--
 .../2018-09-27-13-14-15.bpo-34022.E2cl0r.rst  |  3 +
 8 files changed, 161 insertions(+), 30 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2018-09-27-13-14-15.bpo-34022.E2cl0r.rst

--- a/Doc/library/py_compile.rst
+++ b/Doc/library/py_compile.rst
@@ -92,6 +92,11 @@ byte-code cache files in the directory c
    .. versionchanged:: 3.8
       The *quiet* parameter was added.
 
+   .. versionchanged:: 3.7.2
+      The :envvar:`SOURCE_DATE_EPOCH` environment variable no longer
+      overrides the value of the *invalidation_mode* argument, and determines
+      its default value instead.
+
 
 .. class:: PycInvalidationMode
 
--- a/Lib/test/test_compileall.py
+++ b/Lib/test/test_compileall.py
@@ -209,6 +209,21 @@ class CompileallTestsWithoutSourceEpoch(
     pass
 
 
+
+class CompileallTestsWithSourceEpoch(CompileallTestsBase,
+                                     unittest.TestCase,
+                                     metaclass=SourceDateEpochTestMeta,
+                                     source_date_epoch=True):
+    pass
+
+
+class CompileallTestsWithoutSourceEpoch(CompileallTestsBase,
+                                        unittest.TestCase,
+                                        metaclass=SourceDateEpochTestMeta,
+                                        source_date_epoch=False):
+    pass
+
+
 class EncodingTest(unittest.TestCase):
     """Issue 6716: compileall should escape source code when printing errors
     to stdout."""
@@ -620,6 +635,21 @@ class CommandLineTestsBase:
 
 
 class CommmandLineTestsWithSourceEpoch(CommandLineTestsBase,
+                                       unittest.TestCase,
+                                       metaclass=SourceDateEpochTestMeta,
+                                       source_date_epoch=True):
+    pass
+
+
+class CommmandLineTestsNoSourceEpoch(CommandLineTestsBase,
+                                     unittest.TestCase,
+                                     metaclass=SourceDateEpochTestMeta,
+                                     source_date_epoch=False):
+    pass
+
+
+
+class CommmandLineTestsWithSourceEpoch(CommandLineTestsBase,
                                        unittest.TestCase,
                                        metaclass=SourceDateEpochTestMeta,
                                        source_date_epoch=True):
--- a/Lib/test/test_importlib/source/test_file_loader.py
+++ b/Lib/test/test_importlib/source/test_file_loader.py
@@ -22,6 +22,9 @@ from test.support import make_legacy_pyc
 from test.test_py_compile import without_source_date_epoch
 from test.test_py_compile import SourceDateEpochTestMeta
 
+from test.test_py_compile import without_source_date_epoch
+from test.test_py_compile import SourceDateEpochTestMeta
+
 
 class SimpleTest(abc.LoaderTests):
 
@@ -363,6 +366,17 @@ class SimpleTest(abc.LoaderTests):
 
 
 class SourceDateEpochTestMeta(SourceDateEpochTestMeta,
+                              type(Source_SimpleTest)):
+    pass
+
+
+class SourceDateEpoch_SimpleTest(Source_SimpleTest,
+                                 metaclass=SourceDateEpochTestMeta,
+                                 source_date_epoch=True):
+    pass
+
+
+class SourceDateEpochTestMeta(SourceDateEpochTestMeta,
                               type(Source_SimpleTest)):
     pass
 
--- a/Lib/test/test_py_compile.py
+++ b/Lib/test/test_py_compile.py
@@ -272,5 +272,19 @@ class PyCompileCLITestCase(unittest.Test
         self.assertIn(b'No such file or directory', stderr)
 
 
+class PyCompileTestsWithSourceEpoch(PyCompileTestsBase,
+                                    unittest.TestCase,
+                                    metaclass=SourceDateEpochTestMeta,
+                                    source_date_epoch=True):
+    pass
+
+
+class PyCompileTestsWithoutSourceEpoch(PyCompileTestsBase,
+                                       unittest.TestCase,
+                                       metaclass=SourceDateEpochTestMeta,
+                                       source_date_epoch=False):
+    pass
+
+
 if __name__ == "__main__":
     unittest.main()
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-09-27-13-14-15.bpo-34022.E2cl0r.rst
@@ -0,0 +1,3 @@
+The :envvar:`SOURCE_DATE_EPOCH` environment variable no longer overrides the
+value of the *invalidation_mode* argument to :func:`py_compile.compile`, and
+determines its default value instead.