unix-cpy: Remove unix-cpy. It's no longer needed.

unix-cpy was originally written to get semantic equivalent with CPython
without writing functional tests.  When writing the initial
implementation of uPy it was a long way between lexer and functional
tests, so the half-way test was to make sure that the bytecode was
correct.  The idea was that if the uPy bytecode matched CPython 1-1 then
uPy would be proper Python if the bytecodes acted correctly.  And having
matching bytecode meant that it was less likely to miss some deep
subtlety in the Python semantics that would require an architectural
change later on.

But that is all history and it no longer makes sense to retain the
ability to output CPython bytecode, because:

1. It outputs CPython 3.3 compatible bytecode.  CPython's bytecode
changes from version to version, and seems to have changed quite a bit
in 3.5.  There's no point in changing the bytecode output to match
CPython anymore.

2. uPy and CPy do different optimisations to the bytecode which makes it
harder to match.

3. The bytecode tests are not run.  They were never part of Travis and
are not run locally anymore.

4. The EMIT_CPYTHON option needs a lot of extra source code which adds
heaps of noise, especially in compile.c.

5. Now that there is an extensive test suite (which tests functionality)
there is no need to match the bytecode.  Some very subtle behaviour is
tested with the test suite and passing these tests is a much better
way to stay Python-language compliant, rather than trying to match
CPy bytecode.

1 files changed, 0 insertions, 78 deletions

diff --git a/tests/bytecode/pylib-tests/dummy_threading.py b/tests/bytecode/pylib-tests/dummy_threading.py
deleted file mode 100644
index 1bb7eee33..000000000
--- a/tests/bytecode/pylib-tests/dummy_threading.py
+++ /dev/null
@@ -1,78 +0,0 @@
-"""Faux ``threading`` version using ``dummy_thread`` instead of ``thread``.
-
-The module ``_dummy_threading`` is added to ``sys.modules`` in order
-to not have ``threading`` considered imported.  Had ``threading`` been
-directly imported it would have made all subsequent imports succeed
-regardless of whether ``_thread`` was available which is not desired.
-
-"""
-from sys import modules as sys_modules
-
-import _dummy_thread
-
-# Declaring now so as to not have to nest ``try``s to get proper clean-up.
-holding_thread = False
-holding_threading = False
-holding__threading_local = False
-
-try:
-    # Could have checked if ``_thread`` was not in sys.modules and gone
-    # a different route, but decided to mirror technique used with
-    # ``threading`` below.
-    if '_thread' in sys_modules:
-        held_thread = sys_modules['_thread']
-        holding_thread = True
-    # Must have some module named ``_thread`` that implements its API
-    # in order to initially import ``threading``.
-    sys_modules['_thread'] = sys_modules['_dummy_thread']
-
-    if 'threading' in sys_modules:
-        # If ``threading`` is already imported, might as well prevent
-        # trying to import it more than needed by saving it if it is
-        # already imported before deleting it.
-        held_threading = sys_modules['threading']
-        holding_threading = True
-        del sys_modules['threading']
-
-    if '_threading_local' in sys_modules:
-        # If ``_threading_local`` is already imported, might as well prevent
-        # trying to import it more than needed by saving it if it is
-        # already imported before deleting it.
-        held__threading_local = sys_modules['_threading_local']
-        holding__threading_local = True
-        del sys_modules['_threading_local']
-
-    import threading
-    # Need a copy of the code kept somewhere...
-    sys_modules['_dummy_threading'] = sys_modules['threading']
-    del sys_modules['threading']
-    sys_modules['_dummy__threading_local'] = sys_modules['_threading_local']
-    del sys_modules['_threading_local']
-    from _dummy_threading import *
-    from _dummy_threading import __all__
-
-finally:
-    # Put back ``threading`` if we overwrote earlier
-
-    if holding_threading:
-        sys_modules['threading'] = held_threading
-        del held_threading
-    del holding_threading
-
-    # Put back ``_threading_local`` if we overwrote earlier
-
-    if holding__threading_local:
-        sys_modules['_threading_local'] = held__threading_local
-        del held__threading_local
-    del holding__threading_local
-
-    # Put back ``thread`` if we overwrote, else del the entry we made
-    if holding_thread:
-        sys_modules['_thread'] = held_thread
-        del held_thread
-    else:
-        del sys_modules['_thread']
-    del holding_thread
-
-    del _dummy_thread
-    del sys_modules