Merge branch 'feature/drop_py2_support' into 'master'

Drop support for unsupported Python versions

Closes IDF-1676

See merge request espressif/esp-idf!13622

tools/ci/check_build_warnings.py

@@ -35,8 +35,6 @@ IGNORE_WARNS = [
         r'changes choice state',
         r'crosstool_version_check\.cmake',
         r'CryptographyDeprecationWarning',
-        r'Python 3 versions older than 3.6 are not supported.',
-        r'Support for Python 2 is deprecated and will be removed in future versions.',
         r'Warning: \d+/\d+ app partitions are too small for binary'
     ]
 ]

tools/ci/check_public_headers.py

@@ -141,7 +141,7 @@ class PublicHeaderChecker:
 
     def join(self):
         for t in self.check_threads:
-            while t.isAlive and not self.terminate.is_set():
+            while t.is_alive() and not self.terminate.is_set():
                 t.join(1)  # joins with timeout to respond to keyboard interrupt
 
     # Checks one header calling:

tools/ci/setup_python.sh

@@ -2,9 +2,9 @@
 
 if [ -z ${PYTHON_VER+x} ]; then
     # Use this version of the Python interpreter if it was not defined before.
-    # 3.4.8 is the default python3 interpreter in esp32-ci-env
+    # 3.6.13 is the default python3 interpreter in esp32-ci-env
     # Jobs which doesn't support this version should define PYTHON_VER themselves
-    PYTHON_VER=3.4.8
+    PYTHON_VER=3.6.13
 fi
 
 if [ -f /opt/pyenv/activate ];

tools/idf.py

@@ -1,26 +1,13 @@
 #!/usr/bin/env python
 #
+# SPDX-FileCopyrightText: 2019-2021 Espressif Systems (Shanghai) CO LTD
+#
+# SPDX-License-Identifier: Apache-2.0
+#
 # 'idf.py' is a top-level config/build command line tool for ESP-IDF
 #
 # You don't have to use idf.py, you can use cmake directly
 # (or use cmake in an IDE)
-#
-#
-#
-# Copyright 2019 Espressif Systems (Shanghai) PTE LTD
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
 
 # WARNING: we don't check for Python build-time dependencies until
 # check_environment() function below. If possible, avoid importing
@@ -44,6 +31,7 @@ from pkgutil import iter_modules
 # idf.py extensions. Therefore, pyc file generation is turned off:
 sys.dont_write_bytecode = True
 
+import python_version_checker  # noqa: E402
 from idf_py_actions.errors import FatalError  # noqa: E402
 from idf_py_actions.tools import executable_exists, idf_version, merge_action_lists, realpath  # noqa: E402
 
@@ -93,11 +81,13 @@ def check_environment():
         print_warning('Setting IDF_PATH environment variable: %s' % detected_idf_path)
         os.environ['IDF_PATH'] = detected_idf_path
 
-    # check Python version
-    if sys.version_info[0] < 3:
-        print_warning('WARNING: Support for Python 2 is deprecated and will be removed in future versions.')
-    elif sys.version_info[0] == 3 and sys.version_info[1] < 6:
-        print_warning('WARNING: Python 3 versions older than 3.6 are not supported.')
+    try:
+        # The Python compatibility check could have been done earlier (tools/detect_python.{sh,fish}) but PATH is
+        # not set for import at that time. Even if the check would be done before, the same check needs to be done
+        # here as well (for example one can call idf.py from a not properly set-up environment).
+        python_version_checker.check()
+    except RuntimeError as e:
+        raise FatalError(e)
 
     # check Python dependencies
     checks_output.append('Checking Python dependencies...')

tools/idf_tools.py

@@ -1,6 +1,10 @@
 #!/usr/bin/env python
 # coding=utf-8
 #
+# SPDX-FileCopyrightText: 2019-2021 Espressif Systems (Shanghai) CO LTD
+#
+# SPDX-License-Identifier: Apache-2.0
+#
 # This script helps installing tools required to use the ESP-IDF, and updating PATH
 # to use the installed tools. It can also create a Python virtual environment,
 # and install Python requirements into it.
@@ -23,22 +27,6 @@
 # * To start using the tools, run `eval "$(idf_tools.py export)"` — this will update
 #   the PATH to point to the installed tools and set up other environment variables
 #   needed by the tools.
-#
-###
-#
-# Copyright 2019 Espressif Systems (Shanghai) PTE LTD
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
 
 import argparse
 import contextlib
@@ -60,19 +48,22 @@ from ssl import SSLContext  # noqa: F401
 from tarfile import TarFile  # noqa: F401
 from zipfile import ZipFile
 
+# Important notice: Please keep the lines above compatible with old Pythons so it won't fail with ImportError but with
+# a nice message printed by python_version_checker.check()
 try:
-    from typing import IO, Callable, Optional, Tuple, Union  # noqa: F401
-except ImportError:
-    pass
+    import python_version_checker
 
-try:
-    from urllib.error import ContentTooShortError
-    from urllib.request import urlopen
-    # the following is only for typing annotation
-    from urllib.response import addinfourl  # noqa: F401
-except ImportError:
-    # Python 2
-    from urllib import ContentTooShortError, urlopen  # type: ignore
+    # check the Python version before it will fail with an exception on syntax or package incompatibility.
+    python_version_checker.check()
+except RuntimeError as e:
+    print(e)
+    raise SystemExit(1)
+
+from typing import IO, Callable, Optional, Tuple, Union  # noqa: F401
+from urllib.error import ContentTooShortError
+from urllib.request import urlopen
+# the following is only for typing annotation
+from urllib.response import addinfourl  # noqa: F401
 
 try:
     from exceptions import WindowsError

tools/python_version_checker.py

@@ -0,0 +1,36 @@
+# SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Script for checking the compatibility of the Python interpreter with ESP-IDF.
+#
+# There are related tools/detect_python.{sh,fish} scripts which are called earlier when the paths are not properly
+# set-up and they only intend to prefer the use of Python 3 over Python 2. Why not more? All possible executables
+# (python3.6, python3.7, ...) cannot be hardcoded there and at the end, the user is responsible to set-up a system
+# where "python" or "python3" of compatible version is available.
+
+import sys
+
+try:
+    # Python 2 is not supported anymore but still the old way of typing is used here in order to give a nice Python
+    # version failure and not a typing exception.
+    from typing import Iterable
+except ImportError:
+    pass
+
+OLDEST_PYTHON_SUPPORTED = (3, 6)  # keep it as tuple for comparison with sys.version_info
+
+
+def _ver_to_str(it):  # type: (Iterable) -> str
+    return '.'.join(str(x) for x in it)
+
+
+def is_supported():  # type: () -> bool
+    return sys.version_info[:2] >= OLDEST_PYTHON_SUPPORTED[:2]
+
+
+def check():  # type: () -> None
+    if not is_supported():
+        raise RuntimeError('ESP-IDF supports Python {} or newer but you are using Python {}. Please upgrade your '
+                           'installation as described in the documentation.'.format(_ver_to_str(OLDEST_PYTHON_SUPPORTED),
+                                                                                    _ver_to_str(sys.version_info[:3])))