Define the EntrySizeError message within the error class.

lib/zip/entry.rb

@@ -711,10 +711,10 @@ module Zip
             bytes_written += buf.bytesize
             next unless bytes_written > size && !warned
 
-            message = "entry '#{name}' should be #{size}B, but is larger when inflated."
+            error = ::Zip::EntrySizeError.new(self)
-            raise ::Zip::EntrySizeError, message if ::Zip.validate_entry_sizes
+            raise error if ::Zip.validate_entry_sizes
 
-            warn "WARNING: #{message}"
+            warn "WARNING: #{error.message}"
             warned = true
           end
         end

lib/zip/errors.rb

@@ -4,7 +4,6 @@ module Zip
   class Error < StandardError; end
   class DestinationFileExistsError < Error; end
   class EntryNameError < Error; end
-  class EntrySizeError < Error; end
 
   class CompressionMethodError < Error
     attr_reader :compression_method
@@ -44,6 +43,19 @@ module Zip
     end
   end
 
+  class EntrySizeError < Error
+    attr_reader :entry
+
+    def initialize(entry)
+      super()
+      @entry = entry
+    end
+
+    def message
+      "Entry '#{@entry.name}' should be #{@entry.size}B, but is larger when inflated."
+    end
+  end
+
   class SplitArchiveError < Error
     def message
       'Rubyzip cannot extract from split archives at this time.'

test/file_extract_test.rb

@@ -139,9 +139,10 @@ class ZipFileExtractTest < MiniTest::Test
           error = assert_raises ::Zip::EntrySizeError do
             a_entry.extract
           end
-          assert_equal \
+          assert_equal(
-            "entry 'a' should be 1B, but is larger when inflated.",
+            "Entry 'a' should be 1B, but is larger when inflated.",
             error.message
+          )
         end
       end
     end