fix: prevent test from creating 60MB files on disk

- Modified input_validation_spec.rb to override output_file method
- Changed test file size from 60MB to 51MB (just above limit)
- Added test output files to .gitignore (bad.css, bad.js, test.css)
- Prevents GitHub large file warnings during push

Author: Matt Spurrier

.gitignore

@@ -17,3 +17,8 @@ doc
 .DS_Store
 tmp/
 spec/fixtures/_site/
+
+# Test files that shouldn't be committed
+bad.css
+bad.js
+test.css

spec/input_validation_spec.rb

@@ -339,25 +339,30 @@
   describe "Content validation during compression" do
     context "with oversized files" do
       it "skips compression for files that are too large" do
-        # Create a large content string
-        large_content = 'a' * (60 * 1024 * 1024) # 60MB
+        # Create a large content string just above the 50MB limit
+        large_content = 'a' * (51 * 1024 * 1024) # 51MB
 
         expect(Jekyll.logger).to receive(:warn).with("Jekyll Minifier:", /too large/)
         expect(Jekyll.logger).to receive(:warn).with("Jekyll Minifier:", /Skipping CSS compression/)
 
-        # Create a test compressor with proper site reference
+        # Create a test compressor with proper site reference and mock output_file
         test_compressor = Class.new do
           include Jekyll::Compressor
           attr_accessor :site
 
           def initialize(site)
             @site = site
           end
+
+          # Override output_file to prevent actual disk writes during testing
+          def output_file(dest, content)
+            # Do nothing - prevent file write
+          end
         end
 
         compressor = test_compressor.new(site)
 
-        # Should return original content without compression
+        # Should return without writing to disk
         compressor.output_css('test.css', large_content)
       end
     end