feat: expose MRI C headers and JRuby jars

.github/workflows/ci.yml

@@ -107,13 +107,38 @@ jobs:
       - if: failure() && runner.debug == '1'
         uses: mxschmitt/action-tmate@v3
 
+  examples-native_ext:
+    name: Examples / Native Ext
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby:
+          - 3.3.6
+          - jruby-9.4.9.0
+    defaults:
+      run:
+        working-directory: examples/native_ext
+    steps:
+      - uses: actions/checkout@v4
+      - uses: bazel-contrib/setup-bazel@0.10.0
+        with:
+          bazelrc: common --announce_rc --color=yes
+          repository-cache: examples/native_ext/MODULE.bazel
+      - run: echo ${{ matrix.ruby }} > .ruby-version
+      - run: bazel build ...
+      - if: failure() && runner.debug == '1'
+        uses: mxschmitt/action-tmate@v3
+
   release:
     name: Release
     if: startsWith(github.ref, 'refs/tags/v')
     needs:
       - ruleset
       - examples-gem
       - examples-jekyll
+      - examples-native_ext
     uses: bazel-contrib/.github/.github/workflows/release_ruleset.yaml@v7
     with:
       mount_bazel_caches: false

.gitignore

@@ -1,5 +1,6 @@
 bazel-bin
 bazel-gem
 bazel-out
+bazel-native_ext
 bazel-rules_ruby
 bazel-testlogs

MODULE.bazel

@@ -12,6 +12,8 @@ module(
 # the versions resolved in users repositories.
 bazel_dep(name = "bazel_skylib", version = "1.3.0")
 bazel_dep(name = "platforms", version = "0.0.5")
+bazel_dep(name = "rules_cc", version = "0.0.9")
+bazel_dep(name = "rules_java", version = "7.2.0")
 
 # Ruleset development dependencies.
 bazel_dep(name = "aspect_bazel_lib", version = "2.10.0", dev_dependency = True)

examples/native_ext/.bazelrc

@@ -0,0 +1,6 @@
+# Not ready for the MODULE.lock file yet, as of Bazel 7.0.0 there are still some stability issues.
+common --lockfile_mode=off
+
+# Allow to run Bazel without pre-installed JDK.
+# Docs: https://bazel.build/reference/command-line-reference#flag--java_runtime_version
+build --java_runtime_version=remotejdk_11

examples/native_ext/.ruby-version

@@ -0,0 +1 @@
+jruby-9.4.9.0

examples/native_ext/BUILD

@@ -0,0 +1,25 @@
+load("@rules_cc//cc:defs.bzl", "cc_library")
+load("@rules_java//java:defs.bzl", "java_library")
+
+cc_library(
+    name = "ext_c",
+    srcs = glob([
+        "ext/**/*.c",
+        "ext/**/*.h",
+    ]),
+    target_compatible_with = select({
+        "@ruby//engine:ruby": [],
+        "//conditions:default": ["@platforms//:incompatible"],
+    }),
+    deps = ["@ruby//:headers"],
+)
+
+java_library(
+    name = "ext_java",
+    srcs = glob(["ext/**/*.java"]),
+    target_compatible_with = select({
+        "@ruby//engine:jruby": [],
+        "//conditions:default": ["@platforms//:incompatible"],
+    }),
+    deps = ["@ruby//:jars"],
+)

examples/native_ext/MODULE.bazel

@@ -0,0 +1,19 @@
+"Bazel dependencies"
+
+bazel_dep(name = "platforms", version = "0.0.10", dev_dependency = True)
+bazel_dep(name = "rules_cc", version = "0.1.0", dev_dependency = True)
+bazel_dep(name = "rules_java", version = "8.7.1", dev_dependency = True)
+bazel_dep(name = "rules_ruby", version = "0.0.0", dev_dependency = True)
+local_path_override(
+    module_name = "rules_ruby",
+    path = "../..",
+)
+
+ruby = use_extension("@rules_ruby//ruby:extensions.bzl", "ruby")
+ruby.toolchain(
+    name = "ruby",
+    version_file = "//:.ruby-version",
+)
+use_repo(ruby, "ruby", "ruby_toolchains")
+
+register_toolchains("@ruby_toolchains//:all")

examples/native_ext/ext/c/native_ext.c

@@ -0,0 +1,9 @@
+#include "native_ext.h"
+
+VALUE rb_mNativeExt;
+
+RUBY_FUNC_EXPORTED void
+Init_native_ext(void)
+{
+  rb_mNativeExt = rb_define_module("NativeExt");
+}

examples/native_ext/ext/c/native_ext.h

@@ -0,0 +1,6 @@
+#ifndef NATIVE_EXT_H
+#define NATIVE_EXT_H 1
+
+#include "ruby.h"
+
+#endif /* NATIVE_EXT_H */

examples/native_ext/ext/java/Dummy.java

@@ -0,0 +1,8 @@
+import org.jruby.*;
+import org.jruby.anno.JRubyClass;
+
+@JRubyClass(name = "Dummy")
+public class Dummy {
+  public Dummy() {
+  }
+}

ruby/private/download.bzl

@@ -113,6 +113,15 @@ def _rb_download_impl(repository_ctx):
         # https://www.graalvm.org/dev/reference-manual/ruby/UTF8Locale/
         env.update({"LANG": "en_US.UTF-8"})
 
+    includes = []
+    if repository_ctx.path("dist/include").exists:
+        for hdrdir in repository_ctx.path("dist/include").readdir():
+            if hdrdir.is_dir:
+                includes.append("dist/include/%s" % hdrdir.basename)
+                for archdir in hdrdir.readdir():
+                    if archdir.is_dir and archdir.basename != "ruby":
+                        includes.append("dist/include/%s/%s" % (hdrdir.basename, archdir.basename))
+
     repository_ctx.template(
         "BUILD",
         repository_ctx.attr._build_tpl,
@@ -122,6 +131,7 @@ def _rb_download_impl(repository_ctx):
             "{ruby_binary_name}": ruby_binary_name,
             "{gem_binary_name}": gem_binary_name,
             "{env}": repr(env),
+            "{includes}": repr(includes),
         },
     )
 

ruby/private/download/BUILD.tpl

@@ -1,3 +1,5 @@
+load("@rules_cc//cc:defs.bzl", "cc_library")
+load("@rules_java//java:defs.bzl", "java_import")
 load("@rules_ruby//ruby:defs.bzl", "rb_binary")
 load("@rules_ruby//ruby:toolchain.bzl", "rb_toolchain")
 
@@ -16,6 +18,23 @@ rb_binary(
     main = ":ruby_file",
 )
 
+cc_library(
+    name = "headers",
+    hdrs = glob(
+        ["dist/include/**/*.h"],
+        allow_empty = True,
+    ),
+    includes = {includes},
+)
+
+java_import(
+    name = "jars",
+    jars = glob(
+        ["dist/lib/**/*.jar"],
+        allow_empty = True,
+    ),
+)
+
 rb_toolchain(
     name = "toolchain",
     bundle = select({