Add --dest-dir option to link .so files built by Bundler

Author: kateinoigakukun

lib/ruby_wasm/cli.rb

@@ -53,6 +53,7 @@ def build(args)
         target_triplet: "wasm32-unknown-wasip1",
         profile: "full",
         stdlib: true,
+        dest_dir: nil,
         disable_gems: false,
         gemfile: nil,
         patches: [],
@@ -108,6 +109,10 @@ def build(args)
             options[:disable_gems] = true
           end
 
+          opts.on("--dest-dir PATH", "(Experimental) Destination directory") do |path|
+            options[:dest_dir] = path
+          end
+
           opts.on("-p", "--patch PATCH", "Apply a patch") do |patch|
             options[:patches] << patch
           end
@@ -149,7 +154,9 @@ def do_build_with_force_ruby_platform(options)
 
       require "tmpdir"
 
-      if options[:save_temps]
+      if dest_dir = options[:dest_dir]
+        self.do_build(executor, dest_dir, packager, options)
+      elsif options[:save_temps]
         tmpdir = Dir.mktmpdir
         self.do_build(executor, tmpdir, packager, options)
         @stderr.puts "Temporary files are saved to #{tmpdir}"

lib/ruby_wasm/packager/core.rb

@@ -139,7 +139,7 @@ def _link_gem_exts(executor, build, gem_home)
       adapters = [wasi_adapter]
       dl_openable_libs = []
       dl_openable_libs << [File.join(ruby_root, "usr"), Dir.glob(File.join(ruby_root, "usr", "local", "lib", "ruby", "**", "*.so"))]
-      dl_openable_libs << [gem_home, Dir.glob(File.join(gem_home, "gems", "**", "*.so"))]
+      dl_openable_libs << [gem_home, Dir.glob(File.join(gem_home, "**", "*.so"))]
 
       linker = RubyWasmExt::ComponentLink.new
       linker.use_built_in_libdl(true)

sig/ruby_wasm/packager.rbs

@@ -23,6 +23,7 @@ class RubyWasm::Packager
     src: RubyWasm::Packager::build_source,
     default_exts: String,
     suffix: String,
+    gem_home: String?,
   }
 
   type bytes = String