Drop Python 3.7, support 3.11, improve installation (#134)

- Require Python 3.8 as minimum version
- Remove `setup.py` and create `pyproject.toml`
- Do not run CI tests with Python 3.7
- Run CI tests with Python 3.11
- Read `__version__` in "smart" way: either from metadata of installed
package, or directly from `pyproject.toml`
- Update package version to 0.17.2

.github/workflows/continuous-integration.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.7, 3.8, 3.9, '3.10']
+        python-version: [3.8, 3.9, '3.10', '3.11']
 
     steps:
       - uses: actions/checkout@v2

pyproject.toml

@@ -0,0 +1,36 @@
+[build-system]
+requires = ["setuptools >= 64.0", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name            = "sympde"
+version         = "0.17.2"
+description     = "Symbolic calculus for partial differential equations (and variational forms)"
+readme          = "README.rst"
+requires-python = ">= 3.8, < 3.12"
+license         = {file = "LICENSE"}
+authors         = [{name = "Ahmed Ratnani", email = "ratnaniahmed@gmail.com"}]
+maintainers = [
+    {name = "Yaman Güçlü", email = "yaman.guclu@gmail.com"},
+    {name = "Said Hadjout"},
+]
+keywords     = ["math"]
+classifiers  = ["Programming Language :: Python :: 3"]
+dependencies = [
+    'sympy >= 1.2, < 1.7',
+    'h5py',
+    'pytest',
+    'pyyaml',
+    'numpy',
+    'matplotlib'
+]
+
+[project.urls]
+Repository = "https://github.com/pyccel/sympde"
+
+[tool.setuptools.packages.find]
+include = ["sympde*"]
+namespaces = false
+
+[tool.setuptools.package-data]
+"*" = ["README.rst"]

sympde/version.py

@@ -1 +1,30 @@
-__version__ = "0.17.1"
+def extract_version() -> str:
+    """
+    Returns either the version of the installed package (e.g. "0.17.1") or the
+    one found in pyproject.toml (e.g. "0.17.1-dev (at /project/location)").
+
+    Returns
+    -------
+    str
+        The package version.
+
+    See also
+    --------
+    https://stackoverflow.com/a/76206192
+
+    """
+    from contextlib import suppress
+    from pathlib    import Path
+
+    with suppress(FileNotFoundError, StopIteration):
+        root_dir = Path(__file__).parent.parent
+        with open(root_dir / "pyproject.toml", encoding="utf-8") as pyproject_toml:
+            version_line = next(line for line in pyproject_toml if line.startswith("version"))
+            version = version_line.split("=")[1].strip("'\"\n ")
+            return f"{version}-dev (at {root_dir})"
+
+    import importlib.metadata
+    return importlib.metadata.version(__package__)
+
+
+__version__ = extract_version()