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- Extract process managers to PROCESS_MANAGERS constant for DRY code
- Relax procfile path validation (remove shell metacharacter check)
- Refactor tests to use around hook with ensure clause for proper cleanup
- Close file descriptors properly to avoid leaks

Co-authored-by: Abanoub Ghadban <AbanoubGhadban@users.noreply.github.com>

Author: github-actions[bot]

lib/react_on_rails/dev/process_manager.rb

@@ -8,6 +8,9 @@ class ProcessManager
       # Timeout for version check operations to prevent hanging
       VERSION_CHECK_TIMEOUT = 5
 
+      # Process managers in order of preference
+      PROCESS_MANAGERS = %w[overmind foreman].freeze
+
       class << self
         # Check if a process is available and usable in the current execution context
         # This accounts for bundler context where system commands might be intercepted
@@ -36,8 +39,9 @@ def run_with_process_manager(procfile)
           FileManager.cleanup_stale_files
 
           # Try process managers in order of preference
-          return if run_process_if_available("overmind", ["start", "-f", procfile])
-          return if run_process_if_available("foreman", ["start", "-f", procfile])
+          PROCESS_MANAGERS.each do |pm|
+            return if run_process_if_available(pm, ["start", "-f", procfile])
+          end
 
           show_process_manager_installation_help
           exit 1
@@ -155,11 +159,9 @@ def show_process_manager_installation_help
         end
 
         def valid_procfile_path?(procfile)
-          # Reject paths with shell metacharacters
-          return false if procfile.match?(/[;&|`$(){}\[\]<>]/)
-
-          # Ensure it's a readable file
-          File.readable?(procfile)
+          # system is invoked with args (no shell), so shell metacharacters are safe.
+          # Ensure it's a readable regular file.
+          File.file?(procfile) && File.readable?(procfile)
         rescue StandardError
           false
         end

spec/react_on_rails/dev/process_manager_spec.rb

@@ -5,16 +5,22 @@
 
 RSpec.describe ReactOnRails::Dev::ProcessManager do
   # Suppress stdout/stderr during tests
-  before(:all) do
-    @original_stderr = $stderr
-    @original_stdout = $stdout
-    $stderr = File.open(File::NULL, "w")
-    $stdout = File.open(File::NULL, "w")
-  end
-
-  after(:all) do
-    $stderr = @original_stderr
-    $stdout = @original_stdout
+  around do |example|
+    original_stderr = $stderr
+    original_stdout = $stdout
+    null_stderr = File.open(File::NULL, "w")
+    null_stdout = File.open(File::NULL, "w")
+
+    begin
+      $stderr = null_stderr
+      $stdout = null_stdout
+      example.run
+    ensure
+      $stderr = original_stderr
+      $stdout = original_stdout
+      null_stderr.close
+      null_stdout.close
+    end
   end
 
   describe ".installed?" do