Cover export config binstub edge cases

Author: justin808

lib/shakapacker/utils/misc.rb

@@ -10,7 +10,7 @@ class Misc
       extend FileUtils
 
       NODE_BINSTUB_EXECUTABLES = %w[node nodejs].freeze
-      ENV_FLAGS_WITH_ARGUMENTS = %w[-u --unset -C --chdir].freeze
+      ENV_FLAGS_WITH_ARGUMENTS = %w[-u --unset -C --chdir -P --path -a --argv0].freeze
       private_constant :NODE_BINSTUB_EXECUTABLES
       private_constant :ENV_FLAGS_WITH_ARGUMENTS
 
@@ -60,6 +60,7 @@ def self.js_binstub_executable(path)
           executable = shebang_tokens.first.to_s
         end
 
+        # Preserve direct interpreter paths so stale absolute Node shebangs fail with actionable binstub guidance.
         NODE_BINSTUB_EXECUTABLES.include?(File.basename(executable)) ? executable : nil
       end
     end

spec/shakapacker/export_bundler_config_task_spec.rb

@@ -142,6 +142,15 @@ def capture_stderr
     end
   end
 
+  it "uses the gem version when bin/shakapacker-config is a directory" do
+    Dir.mktmpdir("shakapacker-export-bundler-config-") do |app_path|
+      FileUtils.mkdir_p(File.join(app_path, "bin", "shakapacker-config"))
+      gem_bin_path = File.expand_path("../../lib/install/bin/shakapacker-config", __dir__)
+
+      expect(invoke_task(app_path)).to eq([RbConfig.ruby, gem_bin_path])
+    end
+  end
+
   it "aborts when the Ruby binstub interpreter is missing" do
     Dir.mktmpdir("shakapacker-export-bundler-config-") do |app_path|
       write_app_binstub(app_path, <<~RUBY)

spec/shakapacker/utils_misc_spec.rb

@@ -35,7 +35,7 @@ def with_binstub(contents)
     end
 
     it "returns node for a node `env` shebang with env flags that take arguments" do
-      with_binstub("#!/usr/bin/env -u NODE_PATH -C /tmp node\nconsole.log('legacy')\n") do |path|
+      with_binstub("#!/usr/bin/env -u NODE_PATH -C /tmp -P /opt/node/bin -a node-shim node\nconsole.log('legacy')\n") do |path|
         expect(described_class.js_binstub_executable(path)).to eq "node"
       end
     end