[CI] helpers/tmp_path - use './tmp' for temp file root only on macOS (#…

…3154)

* [CI] helpers/tmp_path - use './tmp' for temp file root only on macOS

See PR #3153

* Create ./tmp if it doesn't exist

test/helpers/tmp_path.rb

@@ -7,8 +7,24 @@ def clean_tmp_paths
 
   private
 
+  # With some macOS configurations, the following error may be raised when
+  # creating a UNIXSocket:
+  #
+  # too long unix socket path (106 bytes given but 104 bytes max) (ArgumentError)
+  #
+  PUMA_TMPDIR =
+    begin
+      if RUBY_PLATFORM.include? 'darwin'
+        dir_temp = File.absolute_path("#{__dir__}/../../tmp")
+        Dir.mkdir dir_temp unless Dir.exist? dir_temp
+        './tmp'
+      else
+        nil
+      end
+    end
+
   def tmp_path(extension=nil)
-    path = Tempfile.create(['', extension], './tmp') { |f| f.path }
+    path = Tempfile.create(['', extension], PUMA_TMPDIR) { |f| f.path }
     tmp_paths << path
     path
   end