chore: update Python version and GitHub Actions to use latest versions

.github/workflows/integration.yml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       matrix:
         os: [ Ubuntu, macOS, Windows ]
-        python-version: [ "3.11" ]
+        python-version: [ "3.12" ]
         project: [ "poetry", "poetry-core" ]
         include:
           - os: Ubuntu
@@ -34,16 +34,16 @@ jobs:
         shell: bash
     steps:
       - name: Checkout Source (${{ matrix.project }})
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           repository: python-poetry/${{ matrix.project }}
 
       - name: Checkout Source (tomlkit)
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           path: tomlkit
 
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -61,7 +61,7 @@ jobs:
         run: echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info))")
 
       - name: Set up cache
-        uses: actions/cache@v3
+        uses: actions/cache@v5
         if: matrix.project != 'poetry-core'
         id: cache
         with:

.github/workflows/release.yml

@@ -11,7 +11,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v6
         with:
           submodules: "recursive"
 
@@ -20,7 +20,7 @@ jobs:
         run: echo ::set-output name=tag::${GITHUB_REF#refs/tags/}
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v6
         with:
           python-version: 3.x
 

.github/workflows/tests.yml

@@ -16,16 +16,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-13, windows-latest]
-        python-version: [3.8, 3.9, "3.10", 3.11, 3.12, 3.13]
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        python-version: [3.9, "3.10", 3.11, 3.12, 3.13, 3.14]
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           submodules: "recursive"
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
           allow-prereleases: true
@@ -46,7 +46,7 @@ jobs:
           poetry env use python
 
       - name: Set up cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         id: cache
         with:
           path: .venv

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Changed
+
+- Drop support for Python older than 3.9. Remove 3.8 from the CI matrix.
+
 ### Added
 
 - Custom encoders can now receive `_parent` and `_sort_keys` parameters to enable proper encoding of nested structures. ([#429](https://github.com/python-poetry/tomlkit/issues/429))

pyproject.toml

@@ -21,7 +21,7 @@ include = [
 ]
 
 [tool.poetry.dependencies]
-python = ">=3.8"
+python = ">=3.9"
 
 [tool.poetry.group.dev.dependencies]
 pytest = "^7.2.0"