Merge RubyGems/Bundler master

fe96fb6e2a

lib/bundler/plugin/api/source.rb

@@ -308,12 +308,6 @@ module Bundler
           Bundler.root
         end
 
-        # @private
-        # Returns true
-        def bundler_plugin_api_source?
-          true
-        end
-
         # @private
         # This API on source might not be stable, and for now we expect plugins
         # to download all specs in `#specs`, so we implement the method for

lib/bundler/rubygems_ext.rb

@@ -4,6 +4,17 @@ require "pathname"
 
 require "rubygems/specification"
 
+# We can't let `Gem::Source` be autoloaded in the `Gem::Specification#source`
+# redefinition below, so we need to load it upfront. The reason is that if
+# Bundler monkeypatches are loaded before RubyGems activates an executable (for
+# example, through `ruby -rbundler -S irb`), gem activation might end up calling
+# the redefined `Gem::Specification#source` and triggering the `Gem::Source`
+# autoload. That would result in requiring "rubygems/source" inside another
+# require, which would trigger a monitor error and cause the `autoload` to
+# eventually fail. A better solution is probably to completely avoid autoloading
+# `Gem::Source` from the redefined `Gem::Specification#source`.
+require "rubygems/source"
+
 require_relative "match_platform"
 
 module Gem
@@ -22,11 +33,7 @@ module Gem
     alias_method :rg_loaded_from,   :loaded_from
 
     def full_gem_path
-      # this cannot check source.is_a?(Bundler::Plugin::API::Source)
-      # because that _could_ trip the autoload, and if there are unresolved
-      # gems at that time, this method could be called inside another require,
-      # thus raising with that constant being undefined. Better to check a method
-      if source.respond_to?(:path) || (source.respond_to?(:bundler_plugin_api_source?) && source.bundler_plugin_api_source?)
+      if source.respond_to?(:root)
         Pathname.new(loaded_from).dirname.expand_path(source.root).to_s.tap{|x| x.untaint if RUBY_VERSION < "2.7" }
       else
         rg_full_gem_path

lib/bundler/vendor/net-http-persistent/lib/net/http/persistent.rb

@@ -174,7 +174,7 @@ class Bundler::Persistent::Net::HTTP::Persistent
   ##
   # The version of Bundler::Persistent::Net::HTTP::Persistent you are using
 
-  VERSION = '4.0.0'
+  VERSION = '4.0.1'
 
   ##
   # Error class for errors raised by Bundler::Persistent::Net::HTTP::Persistent.  Various

lib/rubygems/ext.rb

@@ -16,3 +16,4 @@ require_relative 'ext/configure_builder'
 require_relative 'ext/ext_conf_builder'
 require_relative 'ext/rake_builder'
 require_relative 'ext/cmake_builder'
+require_relative 'ext/cargo_builder'

lib/rubygems/ext/builder.rb

@@ -123,6 +123,9 @@ class Gem::Ext::Builder
       Gem::Ext::RakeBuilder
     when /CMakeLists.txt/ then
       Gem::Ext::CmakeBuilder
+    when /Cargo.toml/ then
+      # We use the spec name here to ensure we invoke the correct init function later
+      Gem::Ext::CargoBuilder.new(@spec)
     else
       build_error("No builder for extension '#{extension}'")
     end

lib/rubygems/ext/cargo_builder.rb

@@ -0,0 +1,305 @@
+# frozen_string_literal: true
+
+# This class is used by rubygems to build Rust extensions. It is a thin-wrapper
+# over the `cargo rustc` command which takes care of building Rust code in a way
+# that Ruby can use.
+class Gem::Ext::CargoBuilder < Gem::Ext::Builder
+  attr_reader :spec
+
+  def initialize(spec)
+    @spec = spec
+  end
+
+  def build(_extension, dest_path, results, args = [], lib_dir = nil, cargo_dir = Dir.pwd)
+    require "rubygems/command"
+    require "fileutils"
+    require "shellwords"
+
+    build_crate(dest_path, results, args, cargo_dir)
+    ext_path = rename_cdylib_for_ruby_compatibility(dest_path)
+    finalize_directory(ext_path, dest_path, lib_dir, cargo_dir)
+    results
+  end
+
+  private
+
+  def build_crate(dest_path, results, args, cargo_dir)
+    manifest = File.join(cargo_dir, "Cargo.toml")
+
+    given_ruby_static = ENV["RUBY_STATIC"]
+
+    ENV["RUBY_STATIC"] = "true" if ruby_static? && !given_ruby_static
+
+    cargo = ENV.fetch("CARGO", "cargo")
+
+    cmd = []
+    cmd += [cargo, "rustc"]
+    cmd += ["--target-dir", dest_path]
+    cmd += ["--manifest-path", manifest]
+    cmd += ["--lib", "--release", "--locked"]
+    cmd += ["--"]
+    cmd += [*cargo_rustc_args(dest_path)]
+    cmd += Gem::Command.build_args
+    cmd += args
+
+    self.class.run cmd, results, self.class.class_name, cargo_dir
+    results
+  ensure
+    ENV["RUBY_STATIC"] = given_ruby_static
+  end
+
+  def cargo_rustc_args(dest_dir)
+    [
+      *linker_args,
+      *mkmf_libpath,
+      *rustc_dynamic_linker_flags(dest_dir),
+      *rustc_lib_flags(dest_dir),
+      *platform_specific_rustc_args(dest_dir),
+      *debug_flags,
+    ]
+  end
+
+  def platform_specific_rustc_args(dest_dir, flags = [])
+    if mingw_target?
+      # On mingw platforms, mkmf adds libruby to the linker flags
+      flags += libruby_args(dest_dir)
+
+      # Make sure ALSR is used on mingw
+      # see https://github.com/rust-lang/rust/pull/75406/files
+      flags += ["-C", "link-arg=-Wl,--dynamicbase"]
+      flags += ["-C", "link-arg=-Wl,--disable-auto-image-base"]
+
+      # If the gem is installed on a host with build tools installed, but is
+      # run on one that isn't the missing libraries will cause the extension
+      # to fail on start.
+      flags += ["-C", "link-arg=-static-libgcc"]
+    end
+
+    flags
+  end
+
+  # We want to use the same linker that Ruby uses, so that the linker flags from
+  # mkmf work properly.
+  def linker_args
+    # Have to handle CC="cl /nologo" on mswin
+    cc_flag = Shellwords.split(makefile_config("CC"))
+    linker = cc_flag.shift
+    link_args = cc_flag.flat_map {|a| ["-C", "link-arg=#{a}"] }
+
+    ["-C", "linker=#{linker}", *link_args]
+  end
+
+  def libruby_args(dest_dir)
+    libs = makefile_config(ruby_static? ? "LIBRUBYARG_STATIC" : "LIBRUBYARG_SHARED")
+    raw_libs = Shellwords.split(libs)
+    raw_libs.flat_map {|l| ldflag_to_link_modifier(l, dest_dir) }
+  end
+
+  def ruby_static?
+    return true if %w[1 true].include?(ENV["RUBY_STATIC"])
+
+    makefile_config("ENABLE_SHARED") == "no"
+  end
+
+  # Ruby expects the dylib to follow a file name convention for loading
+  def rename_cdylib_for_ruby_compatibility(dest_path)
+    dylib_path = validate_cargo_build!(dest_path)
+    dlext_name = "#{spec.name}.#{makefile_config("DLEXT")}"
+    new_name = dylib_path.gsub(File.basename(dylib_path), dlext_name)
+    FileUtils.cp(dylib_path, new_name)
+    new_name
+  end
+
+  def validate_cargo_build!(dir)
+    prefix = so_ext == "dll" ? "" : "lib"
+    dylib_path = File.join(dir, "release", "#{prefix}#{cargo_crate_name}.#{so_ext}")
+
+    raise DylibNotFoundError, dir unless File.exist?(dylib_path)
+
+    dylib_path
+  end
+
+  def cargo_crate_name
+    spec.metadata.fetch('cargo_crate_name', spec.name).tr('-', '_')
+  end
+
+  def rustc_dynamic_linker_flags(dest_dir)
+    split_flags("DLDFLAGS")
+      .map {|arg| maybe_resolve_ldflag_variable(arg, dest_dir) }
+      .compact
+      .flat_map {|arg| ldflag_to_link_modifier(arg, dest_dir) }
+  end
+
+  def rustc_lib_flags(dest_dir)
+    split_flags("LIBS").flat_map {|arg| ldflag_to_link_modifier(arg, dest_dir) }
+  end
+
+  def split_flags(var)
+    Shellwords.split(RbConfig::CONFIG.fetch(var, ""))
+  end
+
+  def ldflag_to_link_modifier(arg, dest_dir)
+    flag = arg[0..1]
+    val = arg[2..-1]
+
+    case flag
+    when "-L" then ["-L", "native=#{val}"]
+    when "-l" then ["-l", val.to_s]
+    when "-F" then ["-l", "framework=#{val}"]
+    else ["-C", "link_arg=#{arg}"]
+    end
+  end
+
+  def link_flag(link_name)
+    # These are provided by the CRT with MSVC
+    # @see https://github.com/rust-lang/pkg-config-rs/blob/49a4ac189aafa365167c72e8e503565a7c2697c2/src/lib.rs#L622
+    return [] if msvc_target? && ["m", "c", "pthread"].include?(link_name)
+
+    if link_name.include?("ruby")
+      # Specify the lib kind and give it the name "ruby" for linking
+      kind = ruby_static? ? "static" : "dylib"
+
+      ["-l", "#{kind}=ruby:#{link_name}"]
+    else
+      ["-l", link_name]
+    end
+  end
+
+  def msvc_target?
+    makefile_config("target_os").include?("msvc")
+  end
+
+  def darwin_target?
+    makefile_config("target_os").include?("darwin")
+  end
+
+  def mingw_target?
+    makefile_config("target_os").include?("mingw")
+  end
+
+  def win_target?
+    target_platform = RbConfig::CONFIG["target_os"]
+    !!Gem::WIN_PATTERNS.find {|r| target_platform =~ r }
+  end
+
+  # Intepolate substition vars in the arg (i.e. $(DEFFILE))
+  def maybe_resolve_ldflag_variable(input_arg, dest_dir)
+    str = input_arg.gsub(/\$\((\w+)\)/) do |var_name|
+      case var_name
+      # On windows, it is assumed that mkmf has setup an exports file for the
+      # extension, so we have to to create one ourselves.
+      when "DEFFILE"
+        write_deffile(dest_dir)
+      else
+        RbConfig::CONFIG[var_name]
+      end
+    end.strip
+
+    str == "" ? nil : str
+  end
+
+  def write_deffile(dest_dir)
+    deffile_path = File.join(dest_dir, "#{spec.name}-#{RbConfig::CONFIG["arch"]}.def")
+    export_prefix = makefile_config("EXPORT_PREFIX") || ""
+
+    File.open(deffile_path, "w") do |f|
+      f.puts "EXPORTS"
+      f.puts "#{export_prefix.strip}Init_#{spec.name}"
+    end
+
+    deffile_path
+  end
+
+  # We have to basically reimplement RbConfig::CONFIG['SOEXT'] here to support
+  # Ruby < 2.5
+  #
+  # @see https://github.com/ruby/ruby/blob/c87c027f18c005460746a74c07cd80ee355b16e4/configure.ac#L3185
+  def so_ext
+    return RbConfig::CONFIG["SOEXT"] if RbConfig::CONFIG.key?("SOEXT")
+
+    if win_target?
+      "dll"
+    elsif darwin_target?
+      "dylib"
+    else
+      "so"
+    end
+  end
+
+  # Corresponds to $(LIBPATH) in mkmf
+  def mkmf_libpath
+    ["-L", "native=#{makefile_config("libdir")}"]
+  end
+
+  def makefile_config(var_name)
+    val = RbConfig::MAKEFILE_CONFIG[var_name]
+
+    return unless val
+
+    RbConfig.expand(val.dup)
+  end
+
+  # Good balance between binary size and debugability
+  def debug_flags
+    ["-C", "debuginfo=1"]
+  end
+
+  # Copied from ExtConfBuilder
+  def finalize_directory(ext_path, dest_path, lib_dir, extension_dir)
+    require "fileutils"
+    require "tempfile"
+
+    begin
+      tmp_dest = Dir.mktmpdir(".gem.", extension_dir)
+
+      # Some versions of `mktmpdir` return absolute paths, which will break make
+      # if the paths contain spaces. However, on Ruby 1.9.x on Windows, relative
+      # paths cause all C extension builds to fail.
+      #
+      # As such, we convert to a relative path unless we are using Ruby 1.9.x on
+      # Windows. This means that when using Ruby 1.9.x on Windows, paths with
+      # spaces do not work.
+      #
+      # Details: https://github.com/rubygems/rubygems/issues/977#issuecomment-171544940
+      tmp_dest_relative = get_relative_path(tmp_dest.clone, extension_dir)
+
+      if tmp_dest_relative
+        full_tmp_dest = File.join(extension_dir, tmp_dest_relative)
+
+        # TODO: remove in RubyGems 3
+        if Gem.install_extension_in_lib && lib_dir
+          FileUtils.mkdir_p lib_dir
+          FileUtils.cp_r ext_path, lib_dir, remove_destination: true
+        end
+
+        FileUtils::Entry_.new(full_tmp_dest).traverse do |ent|
+          destent = ent.class.new(dest_path, ent.rel)
+          destent.exist? || FileUtils.mv(ent.path, destent.path)
+        end
+      end
+    ensure
+      FileUtils.rm_rf tmp_dest if tmp_dest
+    end
+  end
+
+  def get_relative_path(path, base)
+    path[0..base.length - 1] = "." if path.start_with?(base)
+    path
+  end
+
+  # Error raised when no cdylib artifact was created
+  class DylibNotFoundError < StandardError
+    def initialize(dir)
+      files = Dir.glob(File.join(dir, "**", "*")).map {|f| "- #{f}" }.join "\n"
+
+      super <<~MSG
+        Dynamic library not found for Rust extension (in #{dir})
+
+        Make sure you set "crate-type" in Cargo.toml to "cdylib"
+
+        Found files:
+        #{files}
+      MSG
+    end
+  end
+end

test/rubygems/test_gem_ext_cargo_builder.rb

@@ -0,0 +1,148 @@
+# frozen_string_literal: true
+require_relative 'helper'
+require 'rubygems/ext'
+
+class TestGemExtCargoBuilder < Gem::TestCase
+  def setup
+    @orig_env = ENV.to_hash
+
+    @rust_envs = {
+      'CARGO_HOME' => File.join(@orig_env['HOME'], '.cargo'),
+      'RUSTUP_HOME' => File.join(@orig_env['HOME'], '.rustup'),
+    }
+
+    system(@rust_envs, 'cargo', '-V', out: IO::NULL, err: [:child, :out])
+    pend 'cargo not present' unless $?.success?
+
+    super
+  end
+
+  def setup_rust_gem(name)
+    @ext = File.join(@tempdir, 'ext')
+    @dest_path = File.join(@tempdir, 'prefix')
+    @fixture_dir = Pathname.new(File.expand_path("../test_gem_ext_cargo_builder/#{name}/", __FILE__))
+
+    FileUtils.mkdir_p @dest_path
+    FileUtils.cp_r(@fixture_dir.to_s, @ext)
+  end
+
+  def test_build_staticlib
+    skip_unsupported_platforms!
+    setup_rust_gem "rust_ruby_example"
+
+    content = @fixture_dir.join('Cargo.toml').read.gsub("cdylib", "staticlib")
+    File.write(File.join(@ext, 'Cargo.toml'), content)
+
+    output = []
+
+    Dir.chdir @ext do
+      ENV.update(@rust_envs)
+      spec = Gem::Specification.new 'rust_ruby_example', '0.1.0'
+      builder = Gem::Ext::CargoBuilder.new(spec)
+      assert_raise(Gem::Ext::CargoBuilder::DylibNotFoundError) do
+        builder.build nil, @dest_path, output
+      end
+    end
+  end
+
+  def test_build_cdylib
+    skip_unsupported_platforms!
+    setup_rust_gem "rust_ruby_example"
+
+    output = []
+
+    Dir.chdir @ext do
+      ENV.update(@rust_envs)
+      spec = Gem::Specification.new 'rust_ruby_example', '0.1.0'
+      builder = Gem::Ext::CargoBuilder.new(spec)
+      builder.build nil, @dest_path, output
+    end
+
+    output = output.join "\n"
+
+    bundle = File.join(@dest_path, "release/rust_ruby_example.#{RbConfig::CONFIG['DLEXT']}")
+
+    require(bundle)
+
+    assert_match RustRubyExample.reverse('hello'), 'olleh'
+
+    assert_match "Compiling rust_ruby_example v0.1.0", output
+    assert_match "Finished release [optimized] target(s)", output
+  rescue Exception => e
+    pp output if output
+
+    raise(e)
+  end
+
+  def test_build_fail
+    skip_unsupported_platforms!
+    setup_rust_gem "rust_ruby_example"
+
+    output = []
+
+    FileUtils.rm(File.join(@ext, 'src/lib.rs'))
+
+    error = assert_raise(Gem::InstallError) do
+      Dir.chdir @ext do
+        ENV.update(@rust_envs)
+        spec = Gem::Specification.new 'rust_ruby_example', '0.1.0'
+        builder = Gem::Ext::CargoBuilder.new(spec)
+        builder.build nil, @dest_path, output
+      end
+    end
+
+    output = output.join "\n"
+
+    assert_match 'cargo failed', error.message
+  end
+
+  def test_full_integration
+    skip_unsupported_platforms!
+    setup_rust_gem "rust_ruby_example"
+
+    Dir.chdir @ext do
+      require 'tmpdir'
+
+      gem = [@rust_envs, *ruby_with_rubygems_in_load_path, File.expand_path("./../../../bin/gem", __FILE__)]
+
+      Dir.mktmpdir("rust_ruby_example") do |dir|
+        built_gem = File.expand_path(File.join(dir, "rust_ruby_example.gem"))
+        Open3.capture2e(*gem, "build", "rust_ruby_example.gemspec", "--output", built_gem)
+        Open3.capture2e(*gem, "install", "--verbose", "--local", built_gem, *ARGV)
+      end
+
+      stdout_and_stderr_str, status = Open3.capture2e(@rust_envs, *ruby_with_rubygems_in_load_path, "-rrust_ruby_example", "-e", "puts 'Result: ' + RustRubyExample.reverse('hello world')")
+
+      assert status.success?, stdout_and_stderr_str
+      assert_match "Result: #{"hello world".reverse}", stdout_and_stderr_str
+    end
+  end
+
+  def test_custom_name
+    skip_unsupported_platforms!
+    setup_rust_gem "custom_name"
+
+    Dir.chdir @ext do
+      require 'tmpdir'
+
+      gem = [@rust_envs, *ruby_with_rubygems_in_load_path, File.expand_path("./../../../bin/gem", __FILE__)]
+
+      Dir.mktmpdir("custom_name") do |dir|
+        built_gem = File.expand_path(File.join(dir, "custom_name.gem"))
+        Open3.capture2e(*gem, "build", "custom_name.gemspec", "--output", built_gem)
+        Open3.capture2e(*gem, "install", "--verbose", "--local", built_gem, *ARGV)
+      end
+
+      stdout_and_stderr_str, status = Open3.capture2e(@rust_envs, *ruby_with_rubygems_in_load_path, "-rcustom_name", "-e", "puts 'Result: ' + CustomName.say_hello")
+
+      assert status.success?, stdout_and_stderr_str
+      assert_match "Result: Hello world!", stdout_and_stderr_str
+    end
+  end
+
+  def skip_unsupported_platforms!
+    pend "jruby not supported" if java_platform?
+    pend "truffleruby not supported (yet)" if RUBY_ENGINE == 'truffleruby'
+    pend "mswin not supported (yet)" if /mswin/ =~ RUBY_PLATFORM && ENV.key?('GITHUB_ACTIONS')
+  end
+end

test/rubygems/test_gem_ext_cargo_builder/custom_name/.gitignore

@@ -0,0 +1 @@
+target/

test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.lock

@@ -0,0 +1,374 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aho-corasick"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "atty"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
+dependencies = [
+ "hermit-abi",
+ "libc",
+ "winapi",
+]
+
+[[package]]
+name = "autocfg"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
+
+[[package]]
+name = "bindgen"
+version = "0.59.2"
+source = "git+https://github.com/rust-lang/rust-bindgen?rev=f34e4103f304500c96d332f5cecc9067c980d0f9#f34e4103f304500c96d332f5cecc9067c980d0f9"
+dependencies = [
+ "bitflags",
+ "cexpr",
+ "clang-sys",
+ "clap",
+ "env_logger",
+ "lazy_static",
+ "lazycell",
+ "log",
+ "peeking_take_while",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "which",
+]
+
+[[package]]
+name = "bitflags"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
+[[package]]
+name = "clang-sys"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4cc00842eed744b858222c4c9faf7243aafc6d33f92f96935263ef4d8a41ce21"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
+[[package]]
+name = "clap"
+version = "3.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ced1892c55c910c1219e98d6fc8d71f6bddba7905866ce740066d8bfea859312"
+dependencies = [
+ "atty",
+ "bitflags",
+ "indexmap",
+ "os_str_bytes",
+ "strsim",
+ "termcolor",
+ "textwrap",
+]
+
+[[package]]
+name = "custom-name-ext"
+version = "0.1.0"
+dependencies = [
+ "rb-sys",
+]
+
+[[package]]
+name = "either"
+version = "1.6.1"
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test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "custom-name-ext"
+version = "0.1.0"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+# Needed until bindgen has the `allowlist_file` feature
+rb-sys = { git = "https://github.com/ianks/rb-sys", tag = "v0.6.0" }

test/rubygems/test_gem_ext_cargo_builder/custom_name/build.rb

@@ -0,0 +1,21 @@
+if ENV['RUBYOPT'] or defined? Gem
+  ENV.delete 'RUBYOPT'
+
+  require 'rbconfig'
+  cmd = [RbConfig.ruby, '--disable-gems', 'build.rb', *ARGV]
+
+  exec(*cmd)
+end
+
+require 'tmpdir'
+
+lp = File.expand_path("./../../../../../lib", __FILE__)
+gem = ["ruby", "-I#{lp}", File.expand_path("./../../../../../bin/gem", __FILE__)]
+gemspec = File.expand_path("./../custom_name.gemspec", __FILE__)
+
+Dir.mktmpdir("custom_name") do |dir|
+  built_gem = File.expand_path(File.join(dir, "custom_name.gem"))
+  system *gem, "build", gemspec, "--output", built_gem
+  system *gem, "install", "--verbose", "--local", built_gem, *ARGV
+  system %q(ruby -rcustom_name -e "puts 'Result: ' + CustomName.say_hello")
+end

test/rubygems/test_gem_ext_cargo_builder/custom_name/custom_name.gemspec

@@ -0,0 +1,10 @@
+Gem::Specification.new do |s|
+  s.name          = "custom_name"
+  s.version       = "0.1.0"
+  s.summary       = "A Rust extension for Ruby"
+  s.extensions    = ["Cargo.toml"]
+  s.authors       = ["Ian Ker-Seymer"]
+  s.files         = ["Cargo.toml", "Cargo.lock", "src/lib.rs"]
+
+  s.metadata['cargo_crate_name'] = 'custom-name-ext'
+end

test/rubygems/test_gem_ext_cargo_builder/custom_name/src/lib.rs

@@ -0,0 +1,30 @@
+#[macro_use]
+extern crate rb_sys;
+
+use rb_sys::{rb_define_module, rb_define_module_function, rb_utf8_str_new, VALUE};
+use std::ffi::CString;
+
+ruby_extension!();
+
+#[no_mangle]
+unsafe extern "C" fn say_hello(_klass: VALUE) -> VALUE {
+    let cstr = CString::new("Hello world!").unwrap();
+
+    rb_utf8_str_new(cstr.as_ptr(), 12)
+}
+
+#[allow(non_snake_case)]
+#[no_mangle]
+pub extern "C" fn Init_custom_name() {
+    let name = CString::new("CustomName").unwrap();
+    let function_name = CString::new("say_hello").unwrap();
+    // bindgen does not properly detect the arity of the ruby callback function, so we have to transmute
+    let callback = unsafe {
+        std::mem::transmute::<unsafe extern "C" fn(VALUE) -> VALUE, unsafe extern "C" fn() -> VALUE>(
+            say_hello,
+        )
+    };
+    let klass = unsafe { rb_define_module(name.as_ptr()) };
+
+    unsafe { rb_define_module_function(klass, function_name.as_ptr(), Some(callback), 0) }
+}

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/.gitignore

@@ -0,0 +1 @@
+target/

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.lock

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+ "memchr",
+]
+
+[[package]]
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+
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+checksum = "58893f751c9b0412871a09abd62ecd2a00298c6c83befa223ef98c52aef40cbe"
+
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+checksum = "c7342d5883fbccae1cc37a2353b09c87c9b0f3afd73f5fb9bba687a1f733b029"
+dependencies = [
+ "unicode-xid",
+]
+
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+checksum = "864d3e96a899863136fc6e99f3d7cae289dafe43bf2c5ac19b70df7210c0a145"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "rb-sys"
+version = "0.6.0"
+source = "git+https://github.com/ianks/rb-sys?tag=v0.6.0#1aa5b589e86a14e01aba806511818c19f85d71f6"
+dependencies = [
+ "bindgen",
+ "libc",
+ "pkg-config",
+]
+
+[[package]]
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+checksum = "d07a8629359eb56f1e2fb1652bb04212c072a87ba68546a04065d525673ac461"
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+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f497285884f3fcff424ffc933e56d7cbca511def0c9831a7f9b5f6153e3cc89b"
+
+[[package]]
+name = "rust_ruby_example"
+version = "0.1.0"
+dependencies = [
+ "rb-sys",
+]
+
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
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+checksum = "43b2853a4d09f215c24cc5489c992ce46052d359b5109343cbafbf26bc62f8a3"
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+checksum = "bab24d30b911b2376f3a13cc2cd443142f0c81dda04c118693e35b3835757755"
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+ "winapi-util",
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+
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+
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+[[package]]
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+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
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+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a5a7e487e921cf220206864a94a89b6c6905bfc19f1057fa26a4cb360e5c1d2"
+dependencies = [
+ "either",
+ "lazy_static",
+ "libc",
+]
+
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
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+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
+dependencies = [
+ "winapi",
+]
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "rust_ruby_example"
+version = "0.1.0"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+# Needed until bindgen has the `allowlist_file` feature
+rb-sys = { git = "https://github.com/ianks/rb-sys", tag = "v0.6.0" }

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/build.rb

@@ -0,0 +1,21 @@
+if ENV['RUBYOPT'] or defined? Gem
+  ENV.delete 'RUBYOPT'
+
+  require 'rbconfig'
+  cmd = [RbConfig.ruby, '--disable-gems', 'build.rb', *ARGV]
+
+  exec(*cmd)
+end
+
+require 'tmpdir'
+
+lp = File.expand_path("./../../../../../lib", __FILE__)
+gem = ["ruby", "-I#{lp}", File.expand_path("./../../../../../bin/gem", __FILE__)]
+gemspec = File.expand_path("./../rust_ruby_example.gemspec", __FILE__)
+
+Dir.mktmpdir("rust_ruby_example") do |dir|
+  built_gem = File.expand_path(File.join(dir, "rust_ruby_example.gem"))
+  system *gem, "build", gemspec, "--output", built_gem
+  system *gem, "install", "--verbose", "--local", built_gem, *ARGV
+  system %q(ruby -rrust_ruby_example -e "puts 'Result: ' + RustRubyExample.reverse('hello world')")
+end

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/rust_ruby_example.gemspec

@@ -0,0 +1,8 @@
+Gem::Specification.new do |s|
+  s.name          = "rust_ruby_example"
+  s.version       = "0.1.0"
+  s.summary       = "A Rust extension for Ruby"
+  s.extensions    = ["Cargo.toml"]
+  s.authors       = ["Ian Ker-Seymer"]
+  s.files         = ["Cargo.toml", "Cargo.lock", "src/lib.rs"]
+end

test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/src/lib.rs

@@ -0,0 +1,42 @@
+#[macro_use]
+extern crate rb_sys;
+
+use rb_sys::{
+    rb_define_module, rb_define_module_function, rb_string_value_cstr, rb_utf8_str_new, VALUE,
+};
+use std::ffi::{CStr, CString};
+use std::os::raw::{c_char, c_long};
+
+ruby_extension!();
+
+#[inline]
+unsafe fn cstr_to_string(str: *const c_char) -> String {
+    CStr::from_ptr(str).to_string_lossy().into_owned()
+}
+
+#[no_mangle]
+unsafe extern "C" fn pub_reverse(_klass: VALUE, mut input: VALUE) -> VALUE {
+    let ruby_string = cstr_to_string(rb_string_value_cstr(&mut input));
+    let reversed = ruby_string.to_string().chars().rev().collect::<String>();
+    let reversed_cstring = CString::new(reversed).unwrap();
+    let size = ruby_string.len() as c_long;
+
+    rb_utf8_str_new(reversed_cstring.as_ptr(), size)
+}
+
+#[allow(non_snake_case)]
+#[no_mangle]
+pub extern "C" fn Init_rust_ruby_example() {
+    let name = CString::new("RustRubyExample").unwrap();
+    let function_name = CString::new("reverse").unwrap();
+    // bindgen does not properly detect the arity of the ruby callback function, so we have to transmute
+    let callback = unsafe {
+        std::mem::transmute::<
+            unsafe extern "C" fn(VALUE, VALUE) -> VALUE,
+            unsafe extern "C" fn() -> VALUE,
+        >(pub_reverse)
+    };
+    let klass = unsafe { rb_define_module(name.as_ptr()) };
+
+    unsafe { rb_define_module_function(klass, function_name.as_ptr(), Some(callback), 1) }
+}