marcoroth · Oct 26, 2026
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -44,8 +44,14 @@ jobs:
       - name: Render Templates
         run: bundle exec rake templates
 
+      # TODO: Drop `BUNDLE_GEMFILE` and the separate cop test run once https://github.com/rubocop/rubocop-ast/pull/420 is released.
       - name: RuboCop
-        run: bundle exec rubocop
+        env:
+          BUNDLE_GEMFILE: gemfiles/rubocop.gemfile
+        run: |-
+          bundle install
+          bundle exec rubocop
+          bundle exec ruby test/rubocop/includes_assertion_test.rb
 
       - name: Yerba
         run: bundle exec yerba check

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -12,7 +12,7 @@ If you encounter any issues when following along with this file please don't hes
 - [**Clang 21**](https://clang.llvm.org): The compiler used to build this project.
 - [**Clang Format 21**](https://clang.llvm.org/docs/ClangFormat.html): For formatting the project.
 - [**Clang Tidy 21**](https://clang.llvm.org/extra/clang-tidy/): For linting the project.
-- [**Prism Ruby Parser v1.9.0**](https://github.com/ruby/prism/releases/tag/v1.9.0): We use Prism for Parsing the Ruby Source Code in the HTML+ERB files.
+- [**Prism Ruby Parser v2.0.0**](https://github.com/ruby/prism/releases/tag/v2.0.0): We use Prism for Parsing the Ruby Source Code in the HTML+ERB files.
 - [**Ruby**](https://www.ruby-lang.org/en/): We need Ruby as a dependency for `bundler`.
 - [**Bundler**](https://bundler.io): We are using `bundler` to build [`prism`](https://github.com/ruby/prism) from source so we can build `herb` against it.
 - [**Emscripten 5**](https://emscripten.org): For the WebAssembly build of `libherb` so it can be used in the browser using the [`@herb-tools/browser`](https://github.com/marcoroth/herb/blob/main/javascript/packages/browser) package.

diff --git a/Gemfile b/Gemfile
@@ -4,7 +4,7 @@ source "https://rubygems.org"
 
 gemspec
 
-gem "prism", github: "ruby/prism", tag: "v1.9.0"
+gem "prism", github: "ruby/prism", tag: "v2.0.0"
 
 gem "actionview", "~> 8.1", require: "action_view"
 gem "benchmark"
@@ -20,6 +20,7 @@ gem "maxitest", "~> 6.0"
 gem "minitest-difftastic", "~> 0.2"
 gem "nokogiri", "~> 1.19"
 gem "oxc", "~> 0.149.0"
+gem "parallel", "~> 1.27"
 gem "rake", "~> 13.4"
 gem "rake-compiler", "~> 1.3"
 gem "rake-compiler-dock", "~> 1.12"
@@ -28,8 +29,7 @@ gem "rbs-inline", "~> 0.14"
 gem "reactionview", github: "marcoroth/reactionview", branch: "herb-v0.11"
 gem "reline", "~> 0.7"
 gem "rolldown", "~> 1.2"
-gem "rubocop", "~> 1.72"
-gem "rubocop-performance", "~> 1.26.0"
+# TODO: Move `rubocop` and `rubocop-performance` back here from `gemfiles/rubocop.gemfile` once https://github.com/rubocop/rubocop-ast/pull/420 is released.
 gem "sorbet"
 gem "steep", "~> 2.1"
 gem "turbo-rails", "~> 2.0", require: false

diff --git a/Gemfile.lock b/Gemfile.lock
@@ -11,10 +11,10 @@ GIT
 
 GIT
   remote: https://github.com/ruby/prism.git
-  revision: c0e37816e97e23e92524a4070e1b99a4025bc63f
-  tag: v1.9.0
+  revision: e2727368fd9fc2486e2acc8aa513f0cd9e7e02cf
+  tag: v2.0.0
   specs:
-    prism (1.9.0)
+    prism (2.0.0)
 
 PATH
   remote: .
@@ -154,7 +154,6 @@ GEM
     lightningcss (1.33.0-x86_64-darwin)
     lightningcss (1.33.0-x86_64-linux-gnu)
     lightningcss (1.33.0-x86_64-linux-musl)
-    lint_roller (1.1.0)
     lipgloss (0.2.2-aarch64-linux-gnu)
     lipgloss (0.2.2-aarch64-linux-musl)
     lipgloss (0.2.2-arm64-darwin)
@@ -255,7 +254,6 @@ GEM
       erb
       psych (>= 4.0.0)
       tsort
-    regexp_parser (2.11.3)
     reline (0.7.0)
       io-console (~> 0.5)
     rolldown (1.2.8-aarch64-linux-gnu)
@@ -264,25 +262,6 @@ GEM
     rolldown (1.2.8-x86_64-darwin)
     rolldown (1.2.8-x86_64-linux-gnu)
     rolldown (1.2.8-x86_64-linux-musl)
-    rubocop (1.84.0)
-      json (~> 2.3)
-      language_server-protocol (~> 3.17.0.2)
-      lint_roller (~> 1.1.0)
-      parallel (~> 1.10)
-      parser (>= 3.3.0.2)
-      rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 2.9.3, < 3.0)
-      rubocop-ast (>= 1.49.0, < 2.0)
-      ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 2.4.0, < 4.0)
-    rubocop-ast (1.49.0)
-      parser (>= 3.3.7.2)
-      prism (~> 1.7)
-    rubocop-performance (1.26.1)
-      lint_roller (~> 1.1)
-      rubocop (>= 1.75.0, < 2.0)
-      rubocop-ast (>= 1.47.1, < 2.0)
-    ruby-progressbar (1.13.0)
     securerandom (0.4.1)
     sorbet (0.6.13466)
       sorbet-static (= 0.6.13466)
@@ -358,6 +337,7 @@ DEPENDENCIES
   minitest-difftastic (~> 0.2)
   nokogiri (~> 1.19)
   oxc (~> 0.149.0)
+  parallel (~> 1.27)
   prism!
   rake (~> 13.4)
   rake-compiler (~> 1.3)
@@ -367,8 +347,6 @@ DEPENDENCIES
   reactionview!
   reline (~> 0.7)
   rolldown (~> 1.2)
-  rubocop (~> 1.72)
-  rubocop-performance (~> 1.26.0)
   sorbet
   steep (~> 2.1)
   turbo-rails (~> 2.0)

diff --git a/Rakefile b/Rakefile
@@ -7,7 +7,8 @@ require "rake/testtask"
 Rake::TestTask.new(:test) do |t|
   t.libs << "test"
   t.libs << "lib"
-  t.test_files = FileList["test/**/*_test.rb"]
+  # TODO: Drop the `test/rubocop` exclusion once https://github.com/rubocop/rubocop-ast/pull/420 is released and RuboCop is back in the main `Gemfile`.
+  t.test_files = FileList["test/**/*_test.rb"].exclude("test/rubocop/**/*")
 end
 
 Rake::TestTask.new("test:engine") do |t|
@@ -25,7 +26,8 @@ end
 Rake::TestTask.new("test:all") do |t|
   t.libs << "test"
   t.libs << "lib"
-  t.test_files = FileList["test/**/*_test.rb"]
+  # TODO: Drop the `test/rubocop` exclusion once https://github.com/rubocop/rubocop-ast/pull/420 is released and RuboCop is back in the main `Gemfile`.
+  t.test_files = FileList["test/**/*_test.rb"].exclude("test/rubocop/**/*")
 end
 
 task "make" do

diff --git a/bin/integration b/bin/integration
@@ -19,7 +19,9 @@ bin/leaks_parse examples/test.html.erb
 
 bin/lint
 bin/tidy
-bundle exec rubocop
+# TODO: Back to `bundle exec rubocop` once https://github.com/rubocop/rubocop-ast/pull/420 is released.
+BUNDLE_GEMFILE=gemfiles/rubocop.gemfile bundle exec rubocop
+BUNDLE_GEMFILE=gemfiles/rubocop.gemfile bundle exec ruby test/rubocop/includes_assertion_test.rb
 
 echo ""
 echo "Integration successful!"
diff --git a/ext/herb/extconf.rb b/ext/herb/extconf.rb
@@ -19,7 +19,7 @@
 
       Add it to your Gemfile before the herb git reference:
 
-        gem "prism", github: "ruby/prism", tag: "v1.9.0"
+        gem "prism", github: "ruby/prism", tag: "v2.0.0"
         gem "herb", github: "...", branch: "..."
 
       Then run `bundle install` again.
@@ -55,13 +55,10 @@
 $VPATH << "$(srcdir)/../../src/prism"
 $VPATH << "$(srcdir)/../../src/lib"
 $VPATH << "$(srcdir)/../../src/util"
-$VPATH << prism_src_path
-$VPATH << "#{prism_src_path}/util"
 
 $INCFLAGS << " -I#{prism_include_path}"
 $INCFLAGS << " -I#{include_path}"
 $INCFLAGS << " -I#{prism_src_path}"
-$INCFLAGS << " -I#{prism_src_path}/util"
 
 $CFLAGS << " -fvisibility=hidden"
 $CFLAGS << " -DHERB_EXCLUDE_PRETTYPRINT"
@@ -71,32 +68,11 @@
 
 herb_src_files = Dir.glob("#{$srcdir}/../../src/**/*.c").map { |file| file.delete_prefix("../../../../ext/herb/") }.sort
 
-prism_main_files = [
-  "diagnostic.c",
-  "encoding.c",
-  "node.c",
-  "options.c",
-  "pack.c",
-  "prettyprint.c",
-  "prism.c",
-  "regexp.c",
-  "serialize.c",
-  "static_literals.c",
-  "token_type.c"
-]
-
-prism_util_files = [
-  "pm_buffer.c",
-  "pm_char.c",
-  "pm_constant_pool.c",
-  "pm_integer.c",
-  "pm_list.c",
-  "pm_memchr.c",
-  "pm_newline_list.c",
-  "pm_string.c",
-  "pm_strncasecmp.c",
-  "pm_strpbrk.c"
-]
+prism_src_files = Dir.glob("#{prism_src_path}/*.c").map do |file|
+  wrapper = "prism_#{File.basename(file)}"
+  File.write(wrapper, "#include \"#{file}\"\n")
+  wrapper
+end
 
 core_src_files = [
   "extension.c",
@@ -106,7 +82,7 @@
   "parser_options_helpers.c"
 ]
 
-$srcs = core_src_files + herb_src_files + prism_main_files + prism_util_files
+$srcs = core_src_files + herb_src_files + prism_src_files
 
 puts "Sources to be compiled: #{$srcs.inspect}"
 

diff --git a/gemfiles/rubocop.gemfile b/gemfiles/rubocop.gemfile
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+# TODO: Move these gems back into the main `Gemfile` and delete this file once https://github.com/rubocop/rubocop-ast/pull/420 is released.
+
+gem "maxitest", "~> 6.0"
+gem "rubocop", "~> 1.72"
+gem "rubocop-performance", "~> 1.26.0"
diff --git a/gemfiles/rubocop.gemfile.lock b/gemfiles/rubocop.gemfile.lock
@@ -0,0 +1,78 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.3)
+    json (2.21.2)
+    language_server-protocol (3.17.0.6)
+    lint_roller (1.1.0)
+    maxitest (6.2.0)
+      minitest (>= 5.20.0, < 5.28.0)
+    minitest (5.27.0)
+    parallel (1.28.0)
+    parser (3.3.13.0)
+      ast (~> 2.4.1)
+      racc
+    prism (1.9.0)
+    racc (1.8.1)
+    rainbow (3.1.1)
+    regexp_parser (2.13.1)
+    rubocop (1.84.0)
+      json (~> 2.3)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.1.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.49.0, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.49.0)
+      parser (>= 3.3.7.2)
+      prism (~> 1.7)
+    rubocop-performance (1.26.1)
+      lint_roller (~> 1.1)
+      rubocop (>= 1.75.0, < 2.0)
+      rubocop-ast (>= 1.47.1, < 2.0)
+    ruby-progressbar (1.13.0)
+    unicode-display_width (3.3.0)
+      unicode-emoji (~> 4.3)
+    unicode-emoji (4.3.0)
+
+PLATFORMS
+  aarch64-linux-gnu
+  aarch64-linux-musl
+  arm64-darwin
+  ruby
+  x86_64-darwin
+  x86_64-linux-gnu
+  x86_64-linux-musl
+
+DEPENDENCIES
+  maxitest (~> 6.0)
+  rubocop (~> 1.72)
+  rubocop-performance (~> 1.26.0)
+
+CHECKSUMS
+  ast (2.4.3) sha256=954615157c1d6a382bc27d690d973195e79db7f55e9765ac7c481c60bdb4d383
+  bundler (4.0.19) sha256=b48056e4c77fb3853cc47775b5447ede44aaa4f53c32f168014ab4fe86587d47
+  json (2.21.2) sha256=1f1d3b7cf2b3ba1a69beca0bb6db13d5438b80bff3cd54cdaaa620b9b07c1c6a
+  language_server-protocol (3.17.0.6) sha256=5ef2c0c138f8267e1bc631d3328347d354f96724b0af22f2c79516120443b7f0
+  lint_roller (1.1.0) sha256=2c0c845b632a7d172cb849cc90c1bce937a28c5c8ccccb50dfd46a485003cc87
+  maxitest (6.2.0) sha256=bb66472dd3f6565e4db5246826a05ce9096958d9e26ba9a8fdcae20288be1f4f
+  minitest (5.27.0) sha256=2d3b17f8a36fe7801c1adcffdbc38233b938eb0b4966e97a6739055a45fa77d5
+  parallel (1.28.0) sha256=33e6de1484baf2524792d178b0913fc8eb94c628d6cfe45599ad4458c638c970
+  parser (3.3.13.0) sha256=e02f9b63c2fe05b0c68f692ba4df89b3cb113b663964f75d988fbebfd6c3deca
+  prism (1.9.0) sha256=7b530c6a9f92c24300014919c9dcbc055bf4cdf51ec30aed099b06cd6674ef85
+  racc (1.8.1) sha256=4a7f6929691dbec8b5209a0b373bc2614882b55fc5d2e447a21aaa691303d62f
+  rainbow (3.1.1) sha256=039491aa3a89f42efa1d6dec2fc4e62ede96eb6acd95e52f1ad581182b79bc6a
+  regexp_parser (2.13.1) sha256=5aedb6b7c35688f51e86eef17a15374dfd287c83f4ca644b2c5f3ec50a33b44b
+  rubocop (1.84.0) sha256=88dec310153bb685a879f5a7cdb601f6287b8f0ee675d9dc63a17c7204c4190a
+  rubocop-ast (1.49.0) sha256=49c3676d3123a0923d333e20c6c2dbaaae2d2287b475273fddee0c61da9f71fd
+  rubocop-performance (1.26.1) sha256=cd19b936ff196df85829d264b522fd4f98b6c89ad271fa52744a8c11b8f71834
+  ruby-progressbar (1.13.0) sha256=80fc9c47a9b640d6834e0dc7b3c94c9df37f08cb072b7761e4a71e22cff29b33
+  unicode-display_width (3.3.0) sha256=4b7aa66a4b11db50f6f7e98411215cd0dd10eaecb665d36eec5bcacb3fa0b613
+  unicode-emoji (4.3.0) sha256=11c02fa73290378c066bb0562cd4c87d8e1b706fbbe0059ca12746a4244de8ce
+
+BUNDLED WITH
+  4.0.19
diff --git a/java/herb_jni.c b/java/herb_jni.c
@@ -139,17 +139,18 @@ Java_org_herb_Herb_parseRuby(JNIEnv* env, jclass clazz, jstring source) {
     return NULL;
   }
 
-  pm_buffer_t buffer = { 0 };
-  pm_serialize(&parse_result->parser, parse_result->root, &buffer);
+  pm_buffer_t* buffer = pm_buffer_new();
+  pm_serialize(parse_result->parser, parse_result->root, buffer);
 
   jbyteArray result = NULL;
+  size_t length = pm_buffer_length(buffer);
 
-  if (buffer.length > 0) {
-    result = (*env)->NewByteArray(env, (jsize) buffer.length);
-    (*env)->SetByteArrayRegion(env, result, 0, (jsize) buffer.length, (const jbyte*) buffer.value);
+  if (length > 0) {
+    result = (*env)->NewByteArray(env, (jsize) length);
+    (*env)->SetByteArrayRegion(env, result, 0, (jsize) length, (const jbyte*) pm_buffer_value(buffer));
   }
 
-  pm_buffer_free(&buffer);
+  pm_buffer_free(buffer);
   herb_free_ruby_parse_result(parse_result);
   (*env)->ReleaseStringUTFChars(env, source, src);
 

diff --git a/javascript/packages/browser/package.json b/javascript/packages/browser/package.json
@@ -36,7 +36,7 @@
   },
   "dependencies": {
     "@herb-tools/core": "0.11.1",
-    "@ruby/prism": "^1.9.0"
+    "@ruby/prism": "^2.0.0"
   },
   "files": [
     "package.json",

diff --git a/javascript/packages/browser/test/browser.test.ts b/javascript/packages/browser/test/browser.test.ts
@@ -17,7 +17,7 @@ describe("@herb-tools/browser", () => {
   test("version() returns a string", async () => {
     const version = Herb.version
     expect(typeof version).toBe("string")
-    expect(version).toBe("@herb-tools/browser@0.11.1, @herb-tools/core@0.11.1, libprism@1.9.0, libherb@0.11.1 (WebAssembly)")
+    expect(version).toBe("@herb-tools/browser@0.11.1, @herb-tools/core@0.11.1, libprism@2.0.0, libherb@0.11.1 (WebAssembly)")
   })
 
   test("parse() can process a simple template", async () => {

diff --git a/javascript/packages/core/package.json b/javascript/packages/core/package.json
@@ -32,7 +32,7 @@
     }
   },
   "dependencies": {
-    "@ruby/prism": "^1.9.0"
+    "@ruby/prism": "^2.0.0"
   },
   "devDependencies": {},
   "files": [

diff --git a/javascript/packages/core/test/prism-visitor.test.ts b/javascript/packages/core/test/prism-visitor.test.ts
@@ -5,7 +5,7 @@ import { PrismVisitor } from "../src/prism/index.js"
 
 import type { PrismNodes, PrismParseResult } from "../src/prism/index.js"
 
-let parse: (source: string) => PrismParseResult
+let parse: (source: Uint8Array) => PrismParseResult
 
 class CollectingVisitor extends PrismVisitor {
   public names: string[] = []
@@ -28,7 +28,7 @@ class CollectingVisitor extends PrismVisitor {
 const collect = (source: string): string[] => {
   const visitor = new CollectingVisitor()
 
-  visitor.visit(parse(source).value)
+  visitor.visit(parse(new TextEncoder().encode(source)).value)
 
   return visitor.names
 }

diff --git a/javascript/packages/formatter/package.json b/javascript/packages/formatter/package.json
@@ -42,7 +42,7 @@
     "@herb-tools/node-wasm": "0.11.1",
     "@herb-tools/printer": "0.11.1",
     "@herb-tools/rewriter": "0.11.1",
-    "@ruby/prism": "^1.9.0",
+    "@ruby/prism": "^2.0.0",
     "tinyglobby": "^0.2.15"
   },
   "files": [