Use uv run to run the Python-based fuzzer

.github/workflows/ci.yaml

@@ -294,8 +294,6 @@ jobs:
           python-version: ${{ env.PYTHON_VERSION }}
       - name: Install uv
         run: curl -LsSf https://astral.sh/uv/install.sh | sh
-      - name: Install Python requirements
-        run: uv pip install -r scripts/fuzz-parser/requirements.txt --system
       - uses: actions/download-artifact@v4
         name: Download Ruff binary to test
         id: download-cached-binary
@@ -307,7 +305,7 @@ jobs:
           # Make executable, since artifact download doesn't preserve this
           chmod +x ${{ steps.download-cached-binary.outputs.download-path }}/ruff
 
-          python scripts/fuzz-parser/fuzz.py 0-500 --test-executable ${{ steps.download-cached-binary.outputs.download-path }}/ruff
+          uv run scripts/fuzz-parser.py 0-500 --test-executable ${{ steps.download-cached-binary.outputs.download-path }}/ruff
 
   scripts:
     name: "test scripts"

.github/workflows/daily_fuzz.yaml

@@ -37,8 +37,6 @@ jobs:
           python-version: "3.12"
       - name: Install uv
         run: curl -LsSf https://astral.sh/uv/install.sh | sh
-      - name: Install Python requirements
-        run: uv pip install -r scripts/fuzz-parser/requirements.txt --system
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install mold"
@@ -49,7 +47,7 @@ jobs:
         # but this is outweighed by the fact that a release build takes *much* longer to compile in CI
         run: cargo build --locked
       - name: Fuzz
-        run: python scripts/fuzz-parser/fuzz.py $(shuf -i 0-9999999999999999999 -n 1000) --test-executable target/debug/ruff
+        run: uv run scripts/fuzz-parser.py $(shuf -i 0-9999999999999999999 -n 1000) --test-executable target/debug/ruff
 
   create-issue-on-failure:
     name: Create an issue if the daily fuzz surfaced any bugs

crates/ruff_python_parser/CONTRIBUTING.md

@@ -58,19 +58,18 @@ cargo test --package ruff_python_parser
 The Ruff project includes a Python-based fuzzer that can be used to run the parser on
 randomly generated (but syntactically valid) Python source code files.
 
-To run the fuzzer, first install the required dependencies:
+To run the fuzzer, first [install `uv`](https://docs.astral.sh/uv/getting-started/installation/):
 
-```sh
-uv pip install -r scripts/fuzz-parser/requirements.txt
-```
+- Unix: `curl -LsSf https://astral.sh/uv/install.sh | sh`
+- Windows: `powershell -c "irm https://astral.sh/uv/install.ps1 | iex"`
 
 Then, run the fuzzer with the following command:
 
 ```sh
-python scripts/fuzz-parser/fuzz.py
+uv run scripts/fuzz-parser.py
 ```
 
-Refer to the [fuzz.py](https://github.com/astral-sh/ruff/blob/main/scripts/fuzz-parser/fuzz.py)
+Refer to the [fuzz-parser.py](https://github.com/astral-sh/ruff/blob/main/scripts/fuzz-parser.py)
 script for more information or use the `--help` flag to see the available options.
 
 #### CI

pyproject.toml

@@ -111,3 +111,26 @@ version_files = [
   "crates/ruff_wasm/Cargo.toml",
   "scripts/benchmarks/pyproject.toml",
 ]
+
+[tool.uv]
+# Dependencies for our various Python scripts in `scripts/`.
+# These could possibly use inline script metadata, but then the exact
+# version of the dependency installed wouldn't be recorded in `uv.lock`.
+dev-dependencies = [
+    # Required by `generate_known_standard_library.py`
+    "stdlibs>=2022.10.9",
+    # Required by `fuzz-parser.py
+    "pysource-codegen",
+    "pysource-minimize",
+    "rich-argparse",
+    "ruff",
+    "termcolor",
+    # Docs dependencies are deliberately omitted,
+    # as they're unfortunately quite complicated.
+    # See `docs/requirements.txt` and `docs/requirements-insiders.txt`
+    # for the requirements of `generate_mkdocs.py`, `_mdformat_utils.py`
+    # and `check_docs_formatted.py`
+]
+
+[tool.uv.workspace]
+members = []

scripts/fuzz-parser/fuzz.py → scripts/fuzz-parser.py

@@ -1,19 +1,18 @@
 """
 Run the parser on randomly generated (but syntactically valid) Python source-code files.
 
-To install all dependencies for this script into an environment using `uv`, run:
-    uv pip install -r scripts/fuzz-parser/requirements.txt
-
-Example invocations of the script:
+Example invocations of the script using `uv` from the project root
+(which will automatically run the script in an environment
+with all dependencies installed):
 - Run the fuzzer using seeds 0, 1, 2, 78 and 93 to generate the code:
-  `python scripts/fuzz-parser/fuzz.py 0-2 78 93`
+  `uv run scripts/fuzz-parser.py 0-2 78 93`
 - Run the fuzzer concurrently using seeds in range 0-10 inclusive,
   but only reporting bugs that are new on your branch:
-  `python scripts/fuzz-parser/fuzz.py 0-10 --new-bugs-only`
+  `uv run scripts/fuzz-parser.py 0-10 --new-bugs-only`
 - Run the fuzzer concurrently on 10,000 different Python source-code files,
   using a random selection of seeds, and only print a summary at the end
   (the `shuf` command is Unix-specific):
-  `python scripts/fuzz-parser/fuzz.py $(shuf -i 0-1000000 -n 10000) --quiet
+  `uv run scripts/fuzz-parser.py $(shuf -i 0-1000000 -n 10000) --quiet
 """
 
 from __future__ import annotations

scripts/pyproject.toml

@@ -1,8 +1,6 @@
-[project]
-name = "scripts"
-version = "0.0.1"
-dependencies = ["stdlibs"]
-requires-python = ">=3.8"
+# This `pyproject.toml` file provides linting configuration for our Python scripts
+# It doesn't list dev dependencies requried by those scripts;
+# those are listed in the `pyproject.toml` file in the project root.
 
 [tool.black]
 line-length = 88