fix: Update logging to coerce ASCII-8BIT into UTF-8. (#1076)

lib/stripe/util.rb

@@ -416,6 +416,15 @@ def self.wrap_logfmt_value(val)
       # Hopefully val is a string, but protect in case it's not.
       val = val.to_s
 
+      # Some values returned by the server are encoded in ASCII-8BIT before
+      # being parsed as UTF-8 by Marshal. If we don't transform these here, then
+      # puts will fail as it tries to render UTF-8 characters as ASCII-8BIT
+      # which is not valid.
+      if val && val.encoding == Encoding::ASCII_8BIT
+        # Dup the string as it is a frozen literal.
+        val = val.dup.force_encoding("UTF-8")
+      end
+
       if %r{[^\w\-/]} =~ val
         # If the string contains any special characters, escape any double
         # quotes it has, remove newlines, and wrap the whole thing in quotes.

test/stripe/util_test.rb

@@ -397,6 +397,13 @@ def isatty
       should "not error if given a non-string" do
         assert_equal "true", Util.send(:wrap_logfmt_value, true)
       end
+
+      should "handle UTF-8 characters encoded in ASCII-8BIT" do
+        expected_utf8_str = "\"é\"".dup.force_encoding(Encoding::UTF_8.name)
+        ascii_8bit_str = "é".dup.force_encoding(Encoding::ASCII_8BIT.name)
+
+        assert_equal expected_utf8_str, Util.send(:wrap_logfmt_value, ascii_8bit_str)
+      end
     end
   end
 end