Python: Drop support for Python 3.7

Debian 10 is not anymore a supported distro, since Debian 12 was
released on June 10, 2023.  Our supported build platforms as of today
all support at least 3.8 (and all of them except for Ubuntu 20.04
support 3.9):

openSUSE Leap 15.5: 3.6.15 (3.11.2)
CentOS Stream 8:    3.6.8  (3.8.13, 3.9.16, 3.11.4)
CentOS Stream 9:    3.9.17 (3.11.4)
Fedora 37:          3.11.4
Fedora 38:          3.11.4
Debian 11:          3.9.2
Debian 12:          3.11.2
Alpine 3.14, 3.15:  3.9.16
Alpine 3.16, 3.17:  3.10.10
Ubuntu 20.04 LTS:   3.8.10
Ubuntu 22.04 LTS:   3.10.12
NetBSD 9.3:         3.9.13*
FreeBSD 12.4:       3.9.16
FreeBSD 13.1:       3.9.18
OpenBSD 7.2:        3.9.17

Note: NetBSD does not appear to have a default meta-package, but offers
several options, the lowest of which is 3.7.15. However, "python39"
appears to be a pre-requisite to one of the other packages we request
in tests/vm/netbsd.

Since it is safe under our supported platform policy, bump our
minimum supported version of Python to 3.8.  The two most interesting
features to have by default include:

- the importlib.metadata module, whose lack is responsible for over 100
  lines of code in mkvenv.py

- improvements to asyncio, for example asyncio.CancelledError
  inherits from BaseException rather than Exception

In addition, code can now use the assignment operator ':='

Because mypy now learns about importlib.metadata, a small change to
mkvenv.py is needed to pass type checking.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/configure b/configure
index 48ae0fc05abefddb5bcab15eae14c4f8f1efdc7a..e08127045d0c9487951d897dde824434d5e42b9d 100755 (executable)
--- a/configure
+++ b/configure
@@ -552,16 +552,16 @@ if test -n "$linux_arch" && ! test -d "$source_path/linux-headers/asm-$linux_arc
 fi
 
 check_py_version() {
-    # We require python >= 3.7.
+    # We require python >= 3.8.
     # NB: a True python conditional creates a non-zero return code (Failure)
-    "$1" -c 'import sys; sys.exit(sys.version_info < (3,7))'
+    "$1" -c 'import sys; sys.exit(sys.version_info < (3,8))'
 }
 
 first_python=
 if test -z "${PYTHON}"; then
     # A bare 'python' is traditionally python 2.x, but some distros
     # have it as python 3.x, so check in both places.
-    for binary in python3 python python3.11 python3.10 python3.9 python3.8 python3.7; do
+    for binary in python3 python python3.11 python3.10 python3.9 python3.8; do
         if has "$binary"; then
             python=$(command -v "$binary")
             if check_py_version "$python"; then
@@ -952,7 +952,7 @@ then
 fi
 
 if ! check_py_version "$python"; then
-  error_exit "Cannot use '$python', Python >= 3.7 is required." \
+  error_exit "Cannot use '$python', Python >= 3.8 is required." \
              "Use --python=/path/to/python to specify a supported Python." \
              "Maybe try:" \
              "  openSUSE Leap 15.3+: zypper install python39" \

diff --git a/python/Makefile b/python/Makefile
index 7c70dcc8d144f50c0ae7eeeff7108bedd7fcb6e7..1fa4ba2498e6bebe179c8df13bd02aa2a46eef0a 100644 (file)
--- a/python/Makefile
+++ b/python/Makefile
@@ -9,13 +9,13 @@ help:
        @echo "make check-minreqs:"
        @echo "    Run tests in the minreqs virtual environment."
        @echo "    These tests use the oldest dependencies."
-       @echo "    Requires: Python 3.7"
-       @echo "    Hint (Fedora): 'sudo dnf install python3.7'"
+       @echo "    Requires: Python 3.8"
+       @echo "    Hint (Fedora): 'sudo dnf install python3.8'"
        @echo ""
        @echo "make check-tox:"
        @echo "    Run tests against multiple python versions."
        @echo "    These tests use the newest dependencies."
-       @echo "    Requires: Python 3.7 - 3.11, and tox."
+       @echo "    Requires: Python 3.8 - 3.11, and tox."
        @echo "    Hint (Fedora): 'sudo dnf install python3-tox python3.11'"
        @echo "    The variable QEMU_TOX_EXTRA_ARGS can be use to pass extra"
        @echo "    arguments to tox".
@@ -59,7 +59,7 @@ PIP_INSTALL = pip install --disable-pip-version-check
 min-venv: $(QEMU_MINVENV_DIR) $(QEMU_MINVENV_DIR)/bin/activate
 $(QEMU_MINVENV_DIR) $(QEMU_MINVENV_DIR)/bin/activate: setup.cfg tests/minreqs.txt
        @echo "VENV $(QEMU_MINVENV_DIR)"
-       @python3.7 -m venv $(QEMU_MINVENV_DIR)
+       @python3.8 -m venv $(QEMU_MINVENV_DIR)
        @(                                                              \
                echo "ACTIVATE $(QEMU_MINVENV_DIR)";                    \
                . $(QEMU_MINVENV_DIR)/bin/activate;                     \

diff --git a/python/scripts/mkvenv.py b/python/scripts/mkvenv.py
index 4f2349fbb65a451ec6c88ca956a0072d0e70635b..57a24948031499c3144ae24a222e3ade6c5fd644 100644 (file)
--- a/python/scripts/mkvenv.py
+++ b/python/scripts/mkvenv.py
@@ -435,6 +435,7 @@ def _gen_importlib(packages: Sequence[str]) -> Iterator[str]:
     try:
         # First preference: Python 3.8+ stdlib
         from importlib.metadata import (  # type: ignore
+            EntryPoint,
             PackageNotFoundError,
             distribution,
         )
@@ -442,6 +443,7 @@ def _gen_importlib(packages: Sequence[str]) -> Iterator[str]:
         logger.debug("%s", str(exc))
         # Second preference: Commonly available PyPI backport
         from importlib_metadata import (  # type: ignore
+            EntryPoint,
             PackageNotFoundError,
             distribution,
         )
@@ -449,7 +451,8 @@ def _gen_importlib(packages: Sequence[str]) -> Iterator[str]:
     def _generator() -> Iterator[str]:
         for package in packages:
             try:
-                entry_points = distribution(package).entry_points
+                entry_points: Iterator[EntryPoint] = \
+                    iter(distribution(package).entry_points)
             except PackageNotFoundError:
                 continue
 

diff --git a/python/setup.cfg b/python/setup.cfg
index e74b58a8c24a5cc7da393722347884d9d16d8813..f6d2d8a13622f0f8c8e3fef79bf3ac2e9941cbec 100644 (file)
--- a/python/setup.cfg
+++ b/python/setup.cfg
@@ -14,7 +14,6 @@ classifiers =
     Natural Language :: English
     Operating System :: OS Independent
     Programming Language :: Python :: 3 :: Only
-    Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
@@ -22,7 +21,7 @@ classifiers =
     Typing :: Typed
 
 [options]
-python_requires = >= 3.7
+python_requires = >= 3.8
 packages =
     qemu.qmp
     qemu.machine
@@ -76,7 +75,7 @@ exclude = __pycache__,
 
 [mypy]
 strict = True
-python_version = 3.7
+python_version = 3.8
 warn_unused_configs = True
 namespace_packages = True
 warn_unused_ignores = False
@@ -192,7 +191,7 @@ multi_line_output=3
 # of python available on your system to run this test.
 
 [tox:tox]
-envlist = py37, py38, py39, py310, py311
+envlist = py38, py39, py310, py311
 skip_missing_interpreters = true
 
 [testenv]

diff --git a/python/tests/minreqs.txt b/python/tests/minreqs.txt
index 979461be6bb35ecc09ef40459bbe74e624f77681..a3f423efd84ded946ad0c807ab5920df1b554c23 100644 (file)
--- a/python/tests/minreqs.txt
+++ b/python/tests/minreqs.txt
@@ -1,5 +1,5 @@
 # This file lists the ***oldest possible dependencies*** needed to run
-# "make check" successfully under ***Python 3.7***. It is used primarily
+# "make check" successfully under ***Python 3.8***. It is used primarily
 # by GitLab CI to ensure that our stated minimum versions in setup.cfg
 # are truthful and regularly validated.
 #

diff --git a/scripts/qapi/mypy.ini b/scripts/qapi/mypy.ini
index 3463307ddc721cc1a066016c3faadc39d7fc7b63..56e0dfb132788ef517ddb576cab1981a990b051a 100644 (file)
--- a/scripts/qapi/mypy.ini
+++ b/scripts/qapi/mypy.ini
@@ -1,7 +1,7 @@
 [mypy]
 strict = True
 disallow_untyped_calls = False
-python_version = 3.7
+python_version = 3.8
 
 [mypy-qapi.schema]
 disallow_untyped_defs = False