chore: drop Python 3.5 (pybind#3719)

* chore: drop Python 3.5 support

* chore: more fstrings with flynt's help

* ci: drop Python 3.5

* chore: bump dependency versions

* docs: touch up py::args

* tests: remove deprecation warning

* Ban smartquotes

* Very minor tweaks (by-product of reviewing PR pybind#3719).

Co-authored-by: Aaron Gokaslan <[email protected]>
Co-authored-by: Ralf W. Grosse-Kunstleve <[email protected]>

Author: 3 people

.github/CONTRIBUTING.md

@@ -93,19 +93,18 @@ cmake --build build -j4
 
 Tips:
 
-* You can use `virtualenv` (from PyPI) instead of `venv` (which is Python 3
-  only).
+* You can use `virtualenv` (faster, from PyPI) instead of `venv`.
 * You can select any name for your environment folder; if it contains "env" it
   will be ignored by git.
-* If you don’t have CMake 3.14+, just add “cmake” to the pip install command.
+* If you don't have CMake 3.14+, just add "cmake" to the pip install command.
 * You can use `-DPYBIND11_FINDPYTHON=ON` to use FindPython on CMake 3.12+
 * In classic mode, you may need to set `-DPYTHON_EXECUTABLE=/path/to/python`.
   FindPython uses `-DPython_ROOT_DIR=/path/to` or
   `-DPython_EXECUTABLE=/path/to/python`.
 
 ### Configuration options
 
-In CMake, configuration options are given with “-D”. Options are stored in the
+In CMake, configuration options are given with "-D". Options are stored in the
 build directory, in the `CMakeCache.txt` file, so they are remembered for each
 build directory. Two selections are special - the generator, given with `-G`,
 and the compiler, which is selected based on environment variables `CXX` and
@@ -115,7 +114,7 @@ after the initial run.
 The valid options are:
 
 * `-DCMAKE_BUILD_TYPE`: Release, Debug, MinSizeRel, RelWithDebInfo
-* `-DPYBIND11_FINDPYTHON=ON`: Use CMake 3.12+’s FindPython instead of the
+* `-DPYBIND11_FINDPYTHON=ON`: Use CMake 3.12+'s FindPython instead of the
   classic, deprecated, custom FindPythonLibs
 * `-DPYBIND11_NOPYTHON=ON`: Disable all Python searching (disables tests)
 * `-DBUILD_TESTING=ON`: Enable the tests
@@ -257,7 +256,7 @@ The report is sent to stderr; you can pipe it into a file if you wish.
 ### Build recipes
 
 This builds with the Intel compiler (assuming it is in your path, along with a
-recent CMake and Python 3):
+recent CMake and Python):
 
 ```bash
 python3 -m venv venv

.github/workflows/ci.yml

@@ -15,6 +15,8 @@ concurrency:
 
 env:
   PIP_ONLY_BINARY: numpy
+  FORCE_COLOR: 3
+  PYTEST_TIMEOUT: 300
 
 jobs:
   # This is the "main" test suite, which tests a large number of different
@@ -25,7 +27,6 @@ jobs:
       matrix:
         runs-on: [ubuntu-latest, windows-2022, macos-latest]
         python:
-        - '3.5'
         - '3.6'
         - '3.9'
         - '3.10'
@@ -167,7 +168,7 @@ jobs:
     # setuptools
     - name: Setuptools helpers test
       run: pytest tests/extra_setuptools
-      if: "!(matrix.python == '3.5' && matrix.runs-on == 'windows-2022')"
+      if: "!(matrix.runs-on == 'windows-2022')"
 
 
   deadsnakes:
@@ -624,9 +625,9 @@ jobs:
 
   # This tests an "install" with the CMake tools
   install-classic:
-    name: "🐍 3.5 • Debian • x86 •  Install"
+    name: "🐍 3.7 • Debian • x86 •  Install"
     runs-on: ubuntu-latest
-    container: i386/debian:stretch
+    container: i386/debian:buster
 
     steps:
     - uses: actions/checkout@v1
@@ -635,7 +636,7 @@ jobs:
       run: |
         apt-get update
         apt-get install -y git make cmake g++ libeigen3-dev python3-dev python3-pip
-        pip3 install "pytest==3.1.*"
+        pip3 install "pytest==6.*"
 
     - name: Configure for install
       run: >
@@ -704,12 +705,10 @@ jobs:
       fail-fast: false
       matrix:
         python:
-        - 3.5
         - 3.6
         - 3.7
         - 3.8
         - 3.9
-        - pypy-3.6
 
         include:
           - python: 3.9
@@ -810,7 +809,7 @@ jobs:
       fail-fast: false
       matrix:
         python:
-          - 3.5
+          - 3.6
           - 3.7
         std:
           - 14

.pre-commit-config.yaml

@@ -15,7 +15,7 @@
 repos:
 # Standard hooks
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v4.1.0
+  rev: "v4.1.0"
   hooks:
   - id: check-added-large-files
   - id: check-case-conflict
@@ -32,59 +32,64 @@ repos:
 
 # Upgrade old Python syntax
 - repo: https://github.com/asottile/pyupgrade
-  rev: v2.31.0
+  rev: "v2.31.0"
   hooks:
   - id: pyupgrade
-    args: [--py3-plus]
+    args: [--py36-plus]
 
 # Nicely sort includes
 - repo: https://github.com/PyCQA/isort
-  rev: 5.10.1
+  rev: "5.10.1"
   hooks:
   - id: isort
 
 # Black, the code formatter, natively supports pre-commit
 - repo: https://github.com/psf/black
-  rev: 22.1.0 # Keep in sync with blacken-docs
+  rev: "22.1.0" # Keep in sync with blacken-docs
   hooks:
   - id: black
 
 # Also code format the docs
 - repo: https://github.com/asottile/blacken-docs
-  rev: v1.12.1
+  rev: "v1.12.1"
   hooks:
   - id: blacken-docs
     additional_dependencies:
     - black==22.1.0 # keep in sync with black hook
 
 # Changes tabs to spaces
 - repo: https://github.com/Lucas-C/pre-commit-hooks
-  rev: v1.1.11
+  rev: "v1.1.11"
   hooks:
   - id: remove-tabs
 
+- repo: https://github.com/sirosen/texthooks
+  rev: "0.2.2"
+  hooks:
+  - id: fix-ligatures
+  - id: fix-smartquotes
+
 # Autoremoves unused imports
 - repo: https://github.com/hadialqattan/pycln
-  rev: v1.1.0
+  rev: "v1.1.0"
   hooks:
   - id: pycln
 
 # Checking for common mistakes
 - repo: https://github.com/pre-commit/pygrep-hooks
-  rev: v1.9.0
+  rev: "v1.9.0"
   hooks:
   - id: python-check-blanket-noqa
   - id: python-check-blanket-type-ignore
   - id: python-no-log-warn
-  # Python 3.6
-  # - id: python-use-type-annotations
+  - id: python-use-type-annotations
   - id: rst-backticks
   - id: rst-directive-colons
   - id: rst-inline-touching-normal
 
 # Flake8 also supports pre-commit natively (same author)
 - repo: https://github.com/PyCQA/flake8
-  rev: 4.0.1
+  rev: "4.0.1"
   hooks:
   - id: flake8
     additional_dependencies: &flake8_dependencies
@@ -94,14 +99,14 @@ repos:
 
 # Automatically remove noqa that are not used
 - repo: https://github.com/asottile/yesqa
-  rev: v1.3.0
+  rev: "v1.3.0"
   hooks:
   - id: yesqa
     additional_dependencies: *flake8_dependencies
 
 # CMake formatting
 - repo: https://github.com/cheshirekow/cmake-format-precommit
-  rev: v0.6.13
+  rev: "v0.6.13"
   hooks:
   - id: cmake-format
     additional_dependencies: [pyyaml]
@@ -110,7 +115,7 @@ repos:
 
 # Check static types with mypy
 - repo: https://github.com/pre-commit/mirrors-mypy
-  rev: v0.931
+  rev: "v0.931"
   hooks:
   - id: mypy
     args: [--show-error-codes]
@@ -128,15 +133,15 @@ repos:
 
 # Check for spelling
 - repo: https://github.com/codespell-project/codespell
-  rev: v2.1.0
+  rev: "v2.1.0"
   hooks:
   - id: codespell
     exclude: ".supp$"
     args: ["-L", "nd,ot,thist"]
 
 # Check for common shell mistakes
 - repo: https://github.com/shellcheck-py/shellcheck-py
-  rev: v0.8.0.4
+  rev: "v0.8.0.4"
   hooks:
   - id: shellcheck
 

README.rst

@@ -32,9 +32,9 @@ this heavy machinery has become an excessively large and unnecessary
 dependency.
 
 Think of this library as a tiny self-contained version of Boost.Python
-with everything stripped away that isn’t relevant for binding
+with everything stripped away that isn't relevant for binding
 generation. Without comments, the core header files only require ~4K
-lines of code and depend on Python (3.5+, or PyPy) and the C++
+lines of code and depend on Python (3.6+, or PyPy) and the C++
 standard library. This compact implementation was possible thanks to
 some of the new C++11 language features (specifically: tuples, lambda
 functions and variadic templates). Since its creation, this library has
@@ -78,8 +78,8 @@ Goodies
 In addition to the core functionality, pybind11 provides some extra
 goodies:
 
-- Python 3.5+, and PyPy3 7.3 are supported with an implementation-agnostic
-  interface (pybind11 2.9 was the last version to support Python 2).
+- Python 3.6+, and PyPy3 7.3 are supported with an implementation-agnostic
+  interface (pybind11 2.9 was the last version to support Python 2 and 3.5).
 
 - It is possible to bind C++11 lambda functions with captured
   variables. The lambda capture data is stored inside the resulting
@@ -88,8 +88,8 @@ goodies:
 - pybind11 uses C++11 move constructors and move assignment operators
   whenever possible to efficiently transfer custom data types.
 
-- It’s easy to expose the internal storage of custom data types through
-  Pythons’ buffer protocols. This is handy e.g. for fast conversion
+- It's easy to expose the internal storage of custom data types through
+  Pythons' buffer protocols. This is handy e.g. for fast conversion
   between C++ matrix classes like Eigen and NumPy without expensive
   copy operations.
 
@@ -119,7 +119,7 @@ goodies:
 Supported compilers
 -------------------
 
-1. Clang/LLVM 3.3 or newer (for Apple Xcode’s clang, this is 5.0.0 or
+1. Clang/LLVM 3.3 or newer (for Apple Xcode's clang, this is 5.0.0 or
    newer)
 2. GCC 4.8 or newer
 3. Microsoft Visual Studio 2015 Update 3 or newer

docs/advanced/cast/overview.rst

@@ -167,5 +167,4 @@ as arguments and return values, refer to the section on binding :ref:`classes`.
 +------------------------------------+---------------------------+-----------------------------------+
 
 .. [#] ``std::filesystem::path`` is converted to ``pathlib.Path`` and
-   ``os.PathLike`` is converted to ``std::filesystem::path``, but this requires
-   Python 3.6 (for ``__fspath__`` support).
+   ``os.PathLike`` is converted to ``std::filesystem::path``.

docs/advanced/functions.rst

@@ -372,7 +372,7 @@ like so:
 Keyword-only arguments
 ======================
 
-Python 3 introduced keyword-only arguments by specifying an unnamed ``*``
+Python implements keyword-only arguments by specifying an unnamed ``*``
 argument in a function definition:
 
 .. code-block:: python
@@ -395,19 +395,18 @@ argument annotations when registering the function:
     m.def("f", [](int a, int b) { /* ... */ },
           py::arg("a"), py::kw_only(), py::arg("b"));
 
-Note that you currently cannot combine this with a ``py::args`` argument.  This
-feature does *not* require Python 3 to work.
-
 .. versionadded:: 2.6
 
-As of pybind11 2.9, a ``py::args`` argument implies that any following arguments
-are keyword-only, as if ``py::kw_only()`` had been specified in the same
-relative location of the argument list as the ``py::args`` argument.  The
-``py::kw_only()`` may be included to be explicit about this, but is not
-required.  (Prior to 2.9 ``py::args`` may only occur at the end of the argument
-list, or immediately before a ``py::kwargs`` argument at the end).
+A ``py::args`` argument implies that any following arguments are keyword-only,
+as if ``py::kw_only()`` had been specified in the same relative location of the
+argument list as the ``py::args`` argument.  The ``py::kw_only()`` may be
+included to be explicit about this, but is not required.
+
+.. versionchanged:: 2.9
+   This can now be combined with ``py::args``. Before, ``py::args`` could only
+   occur at the end of the argument list, or immediately before a ``py::kwargs``
+   argument at the end.
 
-.. versionadded:: 2.9
 
 Positional-only arguments
 =========================

docs/advanced/pycpp/numpy.rst

@@ -395,7 +395,7 @@ uses of ``py::array``:
 Ellipsis
 ========
 
-Python 3 provides a convenient ``...`` ellipsis notation that is often used to
+Python provides a convenient ``...`` ellipsis notation that is often used to
 slice multidimensional arrays. For instance, the following snippet extracts the
 middle dimensions of a tensor with the first and last index set to zero.
 

docs/benchmark.py

@@ -11,20 +11,20 @@ def generate_dummy_code_pybind11(nclasses=10):
     bindings = ""
 
     for cl in range(nclasses):
-        decl += "class cl%03i;\n" % cl
+        decl += f"class cl{cl:03};\n"
     decl += "\n"
 
     for cl in range(nclasses):
-        decl += "class cl%03i {\n" % cl
+        decl += f"class {cl:03} {{\n"
         decl += "public:\n"
-        bindings += '    py::class_<cl%03i>(m, "cl%03i")\n' % (cl, cl)
+        bindings += f'    py::class_<cl{cl:03}>(m, "cl{cl:03}")\n'
         for fn in range(nfns):
             ret = random.randint(0, nclasses - 1)
             params = [random.randint(0, nclasses - 1) for i in range(nargs)]
-            decl += "    cl%03i *fn_%03i(" % (ret, fn)
-            decl += ", ".join("cl%03i *" % p for p in params)
+            decl += f"    cl{ret:03} *fn_{fn:03}("
+            decl += ", ".join(f"cl{p:03} *" for p in params)
             decl += ");\n"
-            bindings += '        .def("fn_%03i", &cl%03i::fn_%03i)\n' % (fn, cl, fn)
+            bindings += f'        .def("fn_{fn:03}", &cl{cl:03}::fn_{fn:03})\n'
         decl += "};\n\n"
         bindings += "        ;\n"
 
@@ -42,23 +42,20 @@ def generate_dummy_code_boost(nclasses=10):
     bindings = ""
 
     for cl in range(nclasses):
-        decl += "class cl%03i;\n" % cl
+        decl += f"class cl{cl:03};\n"
     decl += "\n"
 
     for cl in range(nclasses):
         decl += "class cl%03i {\n" % cl
         decl += "public:\n"
-        bindings += '    py::class_<cl%03i>("cl%03i")\n' % (cl, cl)
+        bindings += f'    py::class_<cl{cl:03}>("cl{cl:03}")\n'
         for fn in range(nfns):
             ret = random.randint(0, nclasses - 1)
             params = [random.randint(0, nclasses - 1) for i in range(nargs)]
-            decl += "    cl%03i *fn_%03i(" % (ret, fn)
-            decl += ", ".join("cl%03i *" % p for p in params)
+            decl += f"    cl{ret:03} *fn_{fn:03}("
+            decl += ", ".join(f"cl{p:03} *" for p in params)
             decl += ");\n"
-            bindings += (
-                '        .def("fn_%03i", &cl%03i::fn_%03i, py::return_value_policy<py::manage_new_object>())\n'
-                % (fn, cl, fn)
-            )
+            bindings += f'        .def("fn_{fn:03}", &cl{cl:03}::fn_{fn:03}, py::return_value_policy<py::manage_new_object>())\n'
         decl += "};\n\n"
         bindings += "        ;\n"