This reverts commit 0f4ed2cd (though, the tests are retained) and the followup 58ab4b57.

See discussion on bpo-29094.

Don't rebuild generated files based on file modification time
anymore, the action is now explicit. Replace "make touch"
with "make regen-all".

Changes:

* Remove "make touch", Tools/hg/hgtouch.py and .hgtouch
* Add a new "make regen-all" command to rebuild all generated files
* Add subcommands to only generate specific files:

  - regen-ast: Include/Python-ast.h and Python/Python-ast.c
  - regen-grammar: Include/graminit.h and Python/graminit.c
  - regen-opcode-targets: Python/opcode_targets.h

* Add PYTHON_FOR_REGEN variable
* pgen is now only built by by "make regen-grammar"
* Add $(srcdir)/ prefix to paths to source files to handle correctly
  compilation outside the source directory

Oops, I forgot that PermissionError was introduced in Python 3.3!
Replace PermissionError with OSError and check on errno.

Add setUpModule() and tearDownModule() functions to test_site to
save/restore sys.path at the module level to prevent warning if the
user site directory is created, since site.addsitedir() modifies
sys.path.
(cherry picked from commit b85c1369)

DummyFTPServer now calls del_channel() on bind() error to prevent the
following warning in TestIPv6Environment.setUpClass():

Warning -- asyncore.socket_map was modified by test_ftplib
  Before: {}
  After:  {3: <test.test_ftplib.DummyFTPServer 127.0.0.1:0 at ...>}

Use EnvironGuard on BuildExtTestCase to save/restore os.environ, to fix the
following warning:

Warning -- os.environ was modified by test_distutils

MSVCCompiler.initialize() of distutils.msvc9compiler modifies
os.environ.

Replace
   File "<stdin>", line 1, in ?
with
   File "<stdin>", line 1, in <module>.
(cherry picked from commit 8856940c)

* Add Appveyor to Python 2.7 branch

* Adapt AppVeyor config for Python 2

* Replace -j0 with -j2: -j0 is ignored on Python 2
* Replace --slowest with --slow
* Remove --timeout option (it was introduced in Python 3)

Don't set cursorSetReturnsNone to DEFAULT_CURSOR_SET_RETURNS_NONE
anymore if self->myenvobj is set.

Fix a GCC warning on the strange indentation.

Backport the CHILD_ERROR status from master: a test is considered as
failed if a worker process running a test exited with a code
different than zero.

Change also the output: write stdout and stderr of the child process
after the test name, instead of writing it before.

accumulate_result(): don't use time of CHILD_ERROR or INTERRUPTED
results.

Use EnvironGuard on InstallTestCase and UtilTestCase.

Backport fixes from master to prevent the following warning:

Warning -- os.environ was modified by test_distutils

Ignore more generated files and test data downloaded by tests.

In PySlice_IndicesEx, clip the step to [-PY_SSIZE_T_MAX,
PY_SSIZE_T_MAX] rather than [PY_SSIZE_T_MIN, PY_SSIZE_T_MAX].

(cherry picked from commit e6fc7401)

Buildbots don't run tests with -vv and so only log "xxx was modified
by test_xxx" which is not enough to debug such random issue. In many
cases, I'm unable to reproduce the warning and so unable to fix it.

Always logging the value before and value after should help to debug
such warning on buildbots.
(cherry picked from commit ec4b1723)
(cherry picked from commit 22982350235f8c5821b71661a5616423e1c7fcc0)

AsyncoreEchoServer of test_ssl now calls
asyncore.close_all(ignore_all=True) to ensure that
asyncore.socket_map is cleared once the test completes, even if
ConnectionHandler was not correctly unregistered.

Fix the following warning:

Warning -- asyncore.socket_map was modified by test_ssl
  Before: {}
  After:  {6: <test.test_ssl.AsyncoreEchoServer.EchoServer.ConnectionHandler>}
(cherry picked from commit 1dae7450)

Don't test if .git/HEAD file exists, but only if the .git file (or
directory) exists.

Use --short form of git hash.  Use output from "git describe" for tag.

Expected outputs:
1. previous hg
2. previous git
3. updated git

Release (tagged) build:
1. Python 3.7.0a0 (v3.7.0a0:4def2a2901a5, ...
2. Python 3.7.0a0 (v3.7.0a0^0:05f53735, ...
3. Python 3.7.0a0 (v3.7.0a0:05f53735, ...

Development build:
1. Python 3.7.0a0 (default:41df79263a11, ...
2. Python 3.7.0a0 (master:05f53735, ...
3. Python 3.7.0a0 (heads/master-dirty:05f53735, ...

"dirty" means the working tree has uncommitted changes.
See "git help describe" for more info.
(cherry picked from commit 554626ad)
(cherry picked from commit ed512cba78af211da4d83cbb7cc533c39176f374)

To unify running tests in Python 2.7 and Python 3, the test
package can be run as a script.  This is equivalent to running the
test.regrtest module as a script.

Based on commit 5c4b0d06 by Ned
Deily, which is based on original patches by Brett Cannon and Steve
Dower.

Remove also the private _Py_svnversion() function and SVNVERSION
variable.

Note: Py_SubversionRevision() and Py_SubversionShortBranch() are
unchanged, they are part of the public API.

To simplify backports from Python 3, the test.test_support module
was converted into a package and renamed to test.support.  The
test.script_helper module was moved into the test.support package.
Names test.test_support and test.script_helper are left as aliases to
test.support and test.support.script_helper.

(cherry picked from commit d9af73330f46d79cc0c56d369f65ebeec3cb5334)

(cherry picked from commit d1a1def7)

Backport enhancements from master, commits:

* 9c4bfa66: "make tags": remove -t
  option of ctags. The option was kept for backward compatibility,
  but it was completly removed recently. Patch written by Stéphane
  Wirtel.
* cf0ac6a7: Fix "make tags": set
  locale to C to call sort
* 8a543c0b: `make tags` fixes (GH-717)

Ignore more generated files.

(cherry picked from commit 6fde770e)

(cherry picked from commit 85157cd8)

(cherry picked from commit 8e675286)

Reported by Sean Canavan on docs@p.o.

(cherry picked from commit 8526fb74)

[2.7] [3.5] bpo-30070: Fixed leaks and crashes in errors handling in the parser module. (GH-1131). (GH-1185) (#1189)

(cherry picked from commit a79f4c21).
(cherry picked from commit 952a05e4e2cf082b74a1676a2804f1f43a9b7702)

[2.7] bpo-30061: Check if PyObject_Size()/PySequence_Size()/PyMapping_Size() (GH-1096) (GH-1180) (#1183)

raised an error.

(cherry picked from commit bf623ae8)
(cherry picked from commit 680fea4)

PySlice_GetIndicesEx in _ctypes.c.