No commit message

.github/actions/setup-python/action.yml

@@ -0,0 +1,14 @@
+name: Setup Python and UV
+runs:
+  using: "composite"
+  steps:
+    # Use the setup-python action to take advantage of the cache. uv will symlink
+    # to this version
+    - name: Setup system python
+      uses: actions/setup-python@v5
+      with:
+        python-version-file: '.python-version'
+    - name: Install uv
+      uses: astral-sh/setup-uv@v4
+      with:
+        version: "0.5.6"

.github/workflows/android.yml

@@ -59,8 +59,8 @@ jobs:
         uses: mozilla-actions/[email protected]
       - name: Install crown
         run: cargo install --path support/crown
-      - name: Bootstrap Python
-        run: python3 -m pip install --upgrade pip virtualenv
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Bootstrap dependencies
         run: sudo apt update && python3 ./mach bootstrap --skip-lints
       - name: Set up JDK 17

.github/workflows/docs.yml

@@ -13,9 +13,10 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Bootstrap
         run: |
-          python3 -m pip install --upgrade pip
           sudo apt update
           python3 ./mach bootstrap --skip-lints
       - name: Set LIBCLANG_PATH # This is needed for bindgen in mozangle.

.github/workflows/lint.yml

@@ -31,9 +31,8 @@ jobs:
         uses: mozilla-actions/[email protected]
       - name: Set LIBCLANG_PATH env # needed for bindgen in mozangle
         run: echo "LIBCLANG_PATH=/usr/lib/llvm-14/lib" >> $GITHUB_ENV
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.10'
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Install taplo
         uses: baptiste0928/cargo-install@v3
         with:
@@ -46,8 +45,6 @@ jobs:
           locked: true
           # 0.16.2 requires Rust 1.81 or newer.
           version: '0.16.1'
-      - name: Bootstrap Python
-        run: python3 -m pip install --upgrade pip
       - name: Bootstrap dependencies
         run: |
           sudo apt update
@@ -57,4 +54,4 @@ jobs:
         run: |
           python3 ./mach clippy --use-crown --locked -- -- --deny warnings
       - name: Tidy
-        run: python3 ./mach test-tidy --no-progress --all
+        run: python3 ./mach test-tidy --no-progress --all

.github/workflows/linux-wpt.yml

@@ -52,9 +52,10 @@ jobs:
           path: ${{ inputs.profile }}-binary-linux
       - name: unPackage binary
         run: tar -xzf ${{ inputs.profile }}-binary-linux/target.tar.gz
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Bootstrap dependencies
         run: |
-          python3 -m pip install --upgrade pip
           sudo apt update
           sudo apt install -qy --no-install-recommends mesa-vulkan-drivers
           python3 ./mach bootstrap --skip-lints

.github/workflows/linux.yml

@@ -131,13 +131,9 @@ jobs:
       - name: Set LIBCLANG_PATH env # needed for bindgen in mozangle
         if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && !inputs.upload }} # not needed on ubuntu 20.04 used for nightly
         run: echo "LIBCLANG_PATH=/usr/lib/llvm-14/lib" >> $GITHUB_ENV
-      - uses: actions/setup-python@v5
+      - name: Setup Python
         if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
-        with:
-          python-version: '3.10'
-      - name: Bootstrap Python
-        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
-        run: python3 -m pip install --upgrade pip
+        uses: ./.github/actions/setup-python
       - name: Bootstrap dependencies
         if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |

.github/workflows/mac-wpt.yml

@@ -41,15 +41,11 @@ jobs:
       - uses: actions/download-artifact@v4
         with:
           name: ${{ inputs.profile }}-binary-macos
-      # Python 3.13 breaks wptrunner, so pin the version until
-      # web-platform-tests/wpt#48585 is fixed.
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.12'
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Prep test environment
         run: |
           gtar -xzf target.tar.gz
-          python3 -m pip install --upgrade pip
           python3 ./mach bootstrap --skip-lints
       - name: Smoketest
         run: python3 ./mach smoketest --${{ inputs.profile }}

.github/workflows/mac.yml

@@ -77,18 +77,14 @@ jobs:
         if: github.event_name == 'pull_request_target'
         with:
           ref: ${{ github.event.pull_request.head.sha }}
-      # Python 3.13 breaks wptrunner, so pin the version until
-      # web-platform-tests/wpt#48585 is fixed.
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.12'
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Run sccache-cache
         uses: mozilla-actions/[email protected]
       - name: Install crown
         run: cargo install --path support/crown
       - name: Bootstrap
         run: |
-          python3 -m pip install --upgrade pip
           python3 ./mach bootstrap --skip-lints
           brew install gnu-tar
       - name: Build (${{ inputs.profile }})

.github/workflows/main.yml

@@ -20,15 +20,16 @@ jobs:
     outputs:
       configuration: ${{ steps.configuration.outputs.result }}
     steps:
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.10'
       - uses: actions/checkout@v4
         with:
           fetch-depth: 1
           sparse-checkout: |
             python/servo/try_parser.py
+            .github/actions/setup-python
+            .python-version
           sparse-checkout-cone-mode: false
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Get Configuration
         id: configuration
         run: |

.github/workflows/ohos.yml

@@ -53,8 +53,8 @@ jobs:
         uses: mozilla-actions/[email protected]
       - name: Install crown
         run: cargo install --path support/crown
-      - name: Bootstrap Python
-        run: python3 -m pip install --upgrade pip virtualenv
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Bootstrap dependencies
         run: sudo apt update && python3 ./mach bootstrap --skip-lints
       - name: Setup OpenHarmony SDK

.github/workflows/pull-request-wpt-export.yml

@@ -28,10 +28,14 @@ jobs:
           # using the token specified here.
           # See https://github.com/actions/checkout/issues/162.
           token: ${{ secrets.WPT_SYNC_TOKEN }}
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Install requirements
-        run: pip install -r servo/python/requirements.txt
+        run: uv pip install -r servo/python/requirements.txt
       - name: Process pull request
-        run: servo/python/wpt/export.py
+        run: |
+         source .venv/bin/activate
+         servo/python/wpt/export.py
         env:
           GITHUB_CONTEXT: ${{ toJson(github) }}
           WPT_SYNC_TOKEN: ${{ secrets.WPT_SYNC_TOKEN }}

.github/workflows/scheduled-wpt-import.yml

@@ -35,9 +35,10 @@ jobs:
       - uses: actions/download-artifact@v4
         with:
           name: wpt-full-logs-linux-layout-2020
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Prep environment
         run: |
-          python3 -m pip install --upgrade pip
           sudo apt update
           python3 ./mach bootstrap
       - name: Add upstream remote

.github/workflows/try-label.yml

@@ -77,14 +77,15 @@ jobs:
             }
 
             return try_string;
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.10'
       - uses: actions/checkout@v4
         with:
           sparse-checkout: |
             python/servo/try_parser.py
+            .github/actions/setup-python
+            .python-version
           sparse-checkout-cone-mode: false
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Parse Labels
         if: ${{ steps.try_string.outputs.result }}
         id: configuration

.github/workflows/try.yml

@@ -29,15 +29,16 @@ jobs:
     outputs:
       configuration: ${{ steps.configuration.outputs.result }}
     steps:
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.10'
       - uses: actions/checkout@v4
         with:
           fetch-depth: 1
           sparse-checkout: |
             python/servo/try_parser.py
+            .github/actions/setup-python
+            .python-version
           sparse-checkout-cone-mode: false
+      - name: Setup Python
+        uses: ./.github/actions/setup-python
       - name: Get Full Configuration
         id: full_config
         run: |

.github/workflows/windows.yml

@@ -114,13 +114,12 @@ jobs:
           choco install wixtoolset
           echo "C:\\Program Files (x86)\\WiX Toolset v3.11\\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
       - uses: actions/setup-python@v5
+      - name: Setup Python
         if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
-        with:
-          python-version: "3.10"
+        uses: ./.github/actions/setup-python
       - name: Bootstrap
         if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |
-          python -m pip install --upgrade pip
           python mach fetch
           python mach bootstrap-gstreamer
       # For some reason WiX isn't currently on the GitHub runner path. This is a

.python-version

@@ -0,0 +1 @@
+3.12.8

README.md

@@ -15,29 +15,35 @@ For more detailed build instructions, see the Servo book under [Setting up your
 [Building for Android]: https://book.servo.org/hacking/building-for-android.html
 [Building for OpenHarmony]: https://book.servo.org/hacking/building-for-openharmony.html
 
+**NOTE**: In the below steps, please ensure you install at least version 3 of python, preferably the latest version supported on your platform.
+Servo will use its own pinned version of python, which it installs using [`uv`](https://docs.astral.sh/uv).
+The system version is required for now just to bootstrap the process of creating and activating the virtual environment.
+
 ### macOS
 
-- Download and install [`python`](https://www.python.org/downloads/macos/) (version 3.10 to 3.12), [Xcode](https://developer.apple.com/xcode/), and [`brew`](https://brew.sh/).
+- Download and install [`python`](https://www.python.org/downloads/macos/), [Xcode](https://developer.apple.com/xcode/), and [`brew`](https://brew.sh/).
+- Install `uv`: `curl -LsSf https://astral.sh/uv/install.sh | sh` 
 - Install `rustup`: `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
 - Restart your shell to make sure `cargo` is available
 - Install the other dependencies: `./mach bootstrap`
 - Build servoshell: `./mach build`
 
 ### Linux
 
-- Install `curl` and `python` (version 3.10 to 3.12):
-  - Arch: `sudo pacman -S --needed curl python python-pip`
-  - Debian, Ubuntu: `sudo apt install curl python3-pip python3-venv python3-setuptools`
-  - Fedora: `sudo dnf install curl python3 python3-pip python3-devel`
-  - Gentoo: `sudo emerge net-misc/curl dev-python/pip`
+- Install `curl` and `python`:
+  - Arch: `sudo pacman -S --needed curl python`
+  - Debian, Ubuntu: `sudo apt install curl`
+  - Fedora: `sudo dnf install curl python3`
+  - Gentoo: `sudo emerge net-misc/curl`
+- Install `uv`: `curl -LsSf https://astral.sh/uv/install.sh | sh` 
 - Install `rustup`: `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
 - Restart your shell to make sure `cargo` is available
 - Install the other dependencies: `./mach bootstrap`
 - Build servoshell: `./mach build`
 
 ### Windows
 
-- Download and install [`python`](https://www.python.org/downloads/windows/) (version 3.10 to 3.12), [`choco`](https://chocolatey.org/install#individual), and [`rustup`](https://win.rustup.rs/)
+- Download and install [`python`](https://www.python.org/downloads/windows/), [`uv`](https://docs.astral.sh/uv/getting-started/installation/#standalone-installer), [`choco`](https://chocolatey.org/install#individual), and [`rustup`](https://win.rustup.rs/)
   - Be sure to select *Quick install via the Visual Studio Community installer*
 - In the Visual Studio Installer, ensure the following components are installed:
   - **Windows 10 SDK (10.0.19041.0)** (`Microsoft.VisualStudio.Component.Windows10SDK.19041`)

python/mach_bootstrap.py

@@ -131,11 +131,8 @@ def install_virtual_env_requirements(project_path: str, python: str, virtualenv_
     requirements_hash = requirements_hasher.hexdigest()
 
     if marker_hash != requirements_hash:
-        print(" * Upgrading pip...")
-        _process_exec([python, "-m", "pip", "install", "--upgrade", "pip"])
-
         print(" * Installing Python requirements...")
-        _process_exec([python, "-m", "pip", "install", "-I",
+        _process_exec(["uv", "pip", "install",
                        "-r", requirements_paths[0],
                        "-r", requirements_paths[1],
                        "-r", requirements_paths[2]])
@@ -144,14 +141,14 @@ def install_virtual_env_requirements(project_path: str, python: str, virtualenv_
 
 
 def _activate_virtualenv(topdir):
-    virtualenv_path = os.path.join(topdir, "python", "_venv%d.%d" % (sys.version_info[0], sys.version_info[1]))
+    virtualenv_path = os.path.join(topdir, ".venv")
     python = sys.executable
 
     if os.environ.get("VIRTUAL_ENV") != virtualenv_path:
         venv_script_path = os.path.join(virtualenv_path, _get_virtualenv_script_dir())
         if not os.path.exists(virtualenv_path):
             print(" * Setting up virtual environment...")
-            _process_exec([python, "-m", "venv", "--system-site-packages", virtualenv_path])
+            _process_exec(["uv", "venv"])
 
         # This general approach is taken from virtualenv's `activate_this.py`.
         os.environ["PATH"] = os.pathsep.join([venv_script_path, *os.environ.get("PATH", "").split(os.pathsep)])
@@ -171,6 +168,11 @@ def _activate_virtualenv(topdir):
 
     install_virtual_env_requirements(topdir, python, virtualenv_path)
 
+    # Turn off warnings about deprecated syntax in our indirect dependencies.
+    # TODO: find a better approach to do this.
+    import warnings
+    warnings.filterwarnings('ignore', category=SyntaxWarning, module=r'.*.venv')
+
 
 def _ensure_case_insensitive_if_windows():
     # The folder is called 'python'. By deliberately checking for it with the wrong case, we determine if the file

servo-tidy.toml

@@ -117,7 +117,6 @@ directories = [
     "./tests/wpt/mozilla/tests/mozilla/referrer-policy",
     "./tests/wpt/mozilla/tests/webgl",
     "./python/tidy/tests",
-    "./python/_v*",
     "./python/mach",
     # Generated and upstream code combined with our own. Could use cleanup
     "./target",

shell.nix

@@ -84,7 +84,12 @@ stdenv.mkDerivation (androidEnvironment // {
 
     # Build utilities
     cmake dbus gcc git pkg-config which llvm perl yasm m4
-    (python3.withPackages (ps: with ps; [virtualenv pip dbus]))
+
+    # Ensure the Python version is same as the one in `.python-version` file so
+    # that `uv` will just symlink to the one in nix store. Otherwise `uv` will
+    # download a pre-built binary that won't work on nix.
+    (python312.withPackages (ps: with ps; [dbus]))
+    uv
 
     # This pins gnumake to 4.3 since 4.4 breaks jobserver
     # functionality in mozjs and causes builds to be extremely