ci: Add pre-commit GitHub action (#500)

Follow up of #480 adding a pre-commit GH action, fixing last formatting,
and remaining buildifier warnings (split in 3 commit)

---

### Changes are visible to end-users: no

Author: hofbi

.github/workflows/ci.yaml

@@ -40,6 +40,12 @@ jobs:
           {"folder": "e2e/smoke", "bazelversion": "8.0.0"}
         ]
 
+  pre-commit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: pre-commit/action@v3.0.1
+
   verify-bcr-patches:
     runs-on: ubuntu-latest
     steps:
@@ -67,7 +73,7 @@ jobs:
   # For branch protection settings, this job provides a "stable" name that can be used to gate PR merges
   # on "all matrix jobs were successful".
   conclusion:
-    needs: test
+    needs: [test, pre-commit]
     runs-on: ubuntu-latest
     if: always()
     steps:

MODULE.bazel

@@ -12,7 +12,7 @@ module(
 # py_image_layer requires 2.x for the `tar` rule.
 # py_image_layer needs compute_unused_inputs attribute
 # py_image_layer needs repo_mapping fix.
-bazel_dep(name = "aspect_bazel_lib", version = "2.10.0") 
+bazel_dep(name = "aspect_bazel_lib", version = "2.10.0")
 bazel_dep(name = "bazel_skylib", version = "1.4.2")
 bazel_dep(name = "rules_python", version = "0.29.0")
 bazel_dep(name = "platforms", version = "0.0.7")

e2e/repository-rule-deps/rules/import.bzl

@@ -1,3 +1,5 @@
+"""Create the external repository under test."""
+
 load("@bazel_skylib//lib:paths.bzl", "paths")
 
 def _myrepo_impl(repository_ctx):
@@ -22,7 +24,7 @@ myrepo = repository_rule(
     },
 )
 
-def _importer_impl(module_ctx):
+def _importer_impl(_):
     myrepo(name = "myrepo", path = "imported")
 
 importer = module_extension(

examples/pytest/BUILD.bazel

@@ -8,7 +8,7 @@ py_library(
 
 py_pytest_main(
     name = "__test__",
-    chdir = package_name(), # So that test fixtures are available at the correct path
+    chdir = package_name(),  # So that test fixtures are available at the correct path
     deps = [
         "@pypi_coverage//:pkg",
         "@pypi_pytest//:pkg",
@@ -21,13 +21,13 @@ py_test(
         "foo_test.py",
         ":__test__",
     ],
+    data = glob([
+        "fixtures/*.json",
+    ]),
     env_inherit = ["FOO"],
     imports = ["../.."],
     main = ":__test__.py",
     package_collisions = "warning",
-    data = glob([
-        "fixtures/*.json",
-    ]),
     deps = [
         ":__test__",
         ":lib",
@@ -43,13 +43,13 @@ py_test(
         "foo_test.py",
         ":__test__",
     ],
+    data = glob([
+        "fixtures/*.json",
+    ]),
     env_inherit = ["FOO"],
     imports = ["../.."],
     main = ":__test__.py",
     package_collisions = "warning",
-    data = glob([
-        "fixtures/*.json",
-    ]),
     deps = [
         ":__test__",
         ":lib",

examples/pytest/fixtures/hello.json

@@ -1,3 +1,3 @@
 {
   "message": "Hello, world."
-}
+}

examples/virtual_deps/BUILD.bazel

@@ -3,44 +3,50 @@ load("@pypi//:requirements.bzl", "requirement")
 
 py_library(
     name = "greet",
-    imports = ["."],
     srcs = ["greet.py"],
+    imports = ["."],
     virtual_deps = ["cowsay"],
 )
 
 # A library that *looks* like cowsay... but isn't!
 py_library(
     name = "cowsnake",
-    imports = ["cowsnake"],
     srcs = ["cowsnake/cowsay.py"],
+    imports = ["cowsnake"],
     virtual_deps = ["snakesay"],
 )
 
 py_binary(
     name = "app",
     srcs = ["main.py"],
-    resolutions = resolutions.from_requirements([
-        "cowsay",
-    ], requirement),
+    python_version = "3.8.12",
+    resolutions = resolutions.from_requirements(
+        [
+            "cowsay",
+        ],
+        requirement,
+    ),
     deps = [
         ":greet",
     ],
-    python_version = "3.8.12",
 )
 
 # Here we swap out the cowsay module for our own implementation
 py_binary(
     name = "app_snake",
     srcs = ["main.py"],
+    python_version = "3.8.12",
+    resolutions = resolutions.from_requirements(
+        [
+            "snakesay",
+        ],
+        requirement,
+    ).override({
+        "cowsay": ":cowsnake",
+    }),
     deps = [
         ":greet",
     ],
-    resolutions = resolutions.from_requirements([
-        "snakesay",
-    ], requirement).override({
-        "cowsay": ":cowsnake",
-    }),
-    python_version = "3.8.12",
 )
 
 py_pytest_main(
@@ -55,9 +61,12 @@ py_test(
     ],
     main = ":__test__.py",
     package_collisions = "error",
-    resolutions = resolutions.from_requirements([
-        "cowsay",
-    ], requirement),
+    resolutions = resolutions.from_requirements(
+        [
+            "cowsay",
+        ],
+        requirement,
+    ),
     deps = [
         requirement("pytest"),
         ":greet",

examples/virtual_deps/README.md

@@ -2,8 +2,8 @@
 
 The example shows how to use `virtual_deps` feature.
 
- - `greet` is a library that has a virtual dependency on `cowsay`
- - `cowsnake` is a library that implements some of the `cowsay` API
- - `app` is a binary that uses `greet` and resolves the `cowsay` virtual dependency
- - `app_snake` is like `app`, but swaps out `cowsay` for `cowsnake`!
- - `pytest_test` tests `greet` using a resolved `cowsay`
+- `greet` is a library that has a virtual dependency on `cowsay`
+- `cowsnake` is a library that implements some of the `cowsay` API
+- `app` is a binary that uses `greet` and resolves the `cowsay` virtual dependency
+- `app_snake` is like `app`, but swaps out `cowsay` for `cowsnake`!
+- `pytest_test` tests `greet` using a resolved `cowsay`

py/private/toolchain/autodetecting.bzl

@@ -1,4 +1,4 @@
-# buildifier: disable=module-docstring
+"""Autodetecting Python toolchain"""
 
 def _autodetecting_py_wrapper_impl(rctx):
     which_python = rctx.which("python3")

py/private/toolchain/tools.bzl

@@ -120,7 +120,7 @@ package(default_visibility = ["//visibility:public"])
     if "RULES_PY_RELEASE_VERSION" in rctx.os.environ:
         release_version = rctx.os.environ["RULES_PY_RELEASE_VERSION"]
 
-    for tool, cfg in RUST_BIN_CFG.items():
+    for tool in RUST_BIN_CFG.keys():
         filename = "-".join([
             tool,
             TOOLCHAIN_PLATFORMS[rctx.attr.platform].arch,

py/private/virtual.bzl

@@ -62,7 +62,7 @@ def _make_resolution(name, requirement):
 
 def _from_requirements(base, requirement_fn = lambda r: r):
     if type(base) == "list":
-        base = { k: None for k in base }
+        base = {k: None for k in base}
     return _make_resolutions(base, requirement_fn)
 
 resolutions = struct(