chore: add Bazel 8 testing (#39)

* chore: add Bazel 8 testing

* fix: revert rules_uv upgrade

* chore: rules_proto leaked another setup routine for WORKSPACE users

* PYSTAR is now required

* chore: reduce delta

* fix: add a rules_java dependency that protobuf is leaking

* chore: give up on bazel8 without bzlmod

Revert WORKSPACE-only changes

* fix: disable Java toolchain which is causing C++ compiles

* disable python too

Author: alexeagle

.bcr/presubmit.yml

@@ -2,7 +2,7 @@ bcr_test_module:
   module_path: "e2e/smoke"
   matrix:
     platform: ["debian10", "macos", "ubuntu2004", "windows"]
-    bazel: ["7.x"]
+    bazel: ["7.x", "8.x"]
   tasks:
     run_tests:
       name: "Run test module"

.github/workflows/ci.yaml

@@ -18,13 +18,12 @@ concurrency:
 
 jobs:
   test:
-    uses: bazel-contrib/.github/.github/workflows/bazel.yaml@v6
+    uses: bazel-contrib/.github/.github/workflows/bazel.yaml@646899086d7aaee8e532540480f3e91e00596234 # Dec 11 2024
     with:
       folders: '[".", "e2e/smoke", "examples"]'
       exclude: |
         [
-          {"bazelversion": "6.4.0"},
           {"folder": ".", "bzlmodEnabled": false},
           {"folder": "examples", "bzlmodEnabled": false},
-          {"folder": ".", "os": "windows-latest"}
+          {"bazelversion": "8.0.0", "bzlmodEnabled": false},
         ]

MODULE.bazel

@@ -8,7 +8,7 @@ module(
 
 bazel_dep(name = "bazel_features", version = "1.9.0")
 bazel_dep(name = "bazel_skylib", version = "1.4.1")
-bazel_dep(name = "rules_proto", version = "6.0.0")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 bazel_dep(name = "platforms", version = "0.0.10")
 
 bazel_dep(name = "aspect_bazel_lib", version = "2.8.1", dev_dependency = True)

README.md

@@ -1,12 +1,4 @@
-# Pre-built protoc toolchain for Bazel 7
-
-> [!CAUTION]
-> Bazel 8 and recent rules_proto changes broke this toolchain.
-> We don't currently have any plans to address this.
-> Instead, we expect someone on the protobuf team to follow through with the
-> "End Goal" promised in https://protobuf.dev/news/2024-10-01/
-> where this functionality is upstreamed.
-> Follow https://github.com/protocolbuffers/protobuf/issues/19558
+# Pre-built protoc toolchain for Bazel
 
 _#NeverCompileProtocAgain_
 

e2e/smoke/.bazelversion

@@ -0,0 +1 @@
+../../.bazelversion

e2e/smoke/MODULE.bazel

@@ -1,5 +1,5 @@
 bazel_dep(name = "toolchains_protoc", version = "0.0.0")
-bazel_dep(name = "rules_proto", version = "6.0.0-rc2")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 
 local_path_override(
     module_name = "toolchains_protoc",

examples/.bazelrc

@@ -2,8 +2,5 @@
 common --incompatible_enable_proto_toolchain_resolution
 common --@aspect_rules_py//py:interpreter_version=3.9.18
 
-# See https://github.com/bazelbuild/rules_python/issues/1069#issuecomment-1942053014
-common --action_env=RULES_PYTHON_ENABLE_PYSTAR=0
-
 # Force rules_go to disable CGO even though we have a (fake) C++ toolchain registered.
 common --host_platform=//tools:no_cgo_host_platform

examples/.bazelversion

@@ -0,0 +1 @@
+../.bazelversion

examples/.bazelversion

@@ -1,6 +1,5 @@
 load("@rules_go//proto:def.bzl", "go_proto_library")
 load("@rules_proto//proto:defs.bzl", "proto_library")
-load("@rules_python//python:proto.bzl", "py_proto_library")
 
 package(default_visibility = ["//visibility:public"])
 
@@ -10,15 +9,21 @@ proto_library(
     deps = ["@com_google_protobuf//:any_proto"],
 )
 
-py_proto_library(
-    name = "foo_py_proto",
-    deps = [":foo_proto"],
-)
+# Broken because rules_python's py_proto_library doesnt produce the same
+# PyInfo symbol that py_test expects.
+# load("@rules_python//python:proto.bzl", "py_proto_library")
+# py_proto_library(
+#     name = "foo_py_proto",
+#     deps = [":foo_proto"],
+# )
 
-java_proto_library(
-    name = "foo_java_proto",
-    deps = [":foo_proto"],
-)
+# Broken by https://github.com/protocolbuffers/protobuf/pull/19679
+# which causes building C++ code from source.
+# TODO: re-enable once protobuf honors the toolchain
+# java_proto_library(
+#     name = "foo_java_proto",
+#     deps = [":foo_proto"],
+# )
 
 go_proto_library(
     name = "foo_go_proto",