Shim IO#pread when not supported

.github/workflows/ci.yml

@@ -8,26 +8,35 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-latest
-    name: "Ruby ${{ matrix.ruby }} / Failure allowed: ${{ matrix.experimental }}"
+    runs-on: ${{ matrix.os }}-latest
+    name: "Ruby ${{ matrix.ruby }} / ${{ matrix.os }} / Failure allowed: ${{ matrix.experimental }}"
     continue-on-error: ${{ matrix.experimental }}
     timeout-minutes: 5
 
     strategy:
       fail-fast: false
       matrix:
+        os: ["ubuntu"]
         ruby: ["2.6", "2.7", "3.0", "3.1", "3.2"]
         experimental: [false]
         include:
+          - ruby: "3.2"
+            os: "windows"
+            experimental: false
           - ruby: "ruby-head"
+            os: "ubuntu"
             experimental: true
           - ruby: "truffleruby-head"
+            os: "ubuntu"
             experimental: true
           - ruby: "jruby-head"
+            os: "ubuntu"
             experimental: true
           - ruby: "jruby-9.3.9.0"
+            os: "ubuntu"
             experimental: true
           - ruby: "jruby-9.4.0.0"
+            os: "ubuntu"
             experimental: true
     steps:
       - uses: actions/checkout@v3

lib/mini_mime.rb

@@ -85,14 +85,40 @@ def fetch(key, &blk)
       end
     end
 
+    if ::File.method_defined?(:pread)
+      PReadFile = ::File
+    else
+      # For Windows support
+      class PReadFile
+        def initialize(filename)
+          @mutex = Mutex.new
+          # We must open the file in binary mode
+          # otherwise Ruby's automatic line terminator
+          # translation will skew the row size
+          @file = ::File.open(filename, 'rb')
+        end
+
+        def readline(*args)
+          @file.readline(*args)
+        end
+
+        def pread(size, offset)
+          @mutex.synchronize do
+            @file.seek(offset, IO::SEEK_SET)
+            @file.read(size)
+          end
+        end
+      end
+    end
+
     class RandomAccessDb
       MAX_CACHED = 100
 
       def initialize(path, sort_order)
         @path = path
-        @file = File.open(@path)
+        @file = PReadFile.new(@path)
 
-        @row_length = @file.readline.length
+        @row_length = @file.readline("\n").length
         @file_length = File.size(@path)
         @rows = @file_length / @row_length
 

test/mini_mime_test.rb

@@ -56,12 +56,64 @@ def should_prioritize_extensions_correctly
   end
 
   if defined? MIME::Types
+    WINDOWS_TYPES = {
+      "cu" => "application/cu-seeme",
+      "ecma" => "application/ecmascript",
+      "es" => "application/ecmascript",
+      "jar" => "application/java-archive",
+      "ser" => "application/java-serialized-object",
+      "mp4" => "application/mp4",
+      "mpg4" => "application/mp4",
+      "doc" => "application/msword",
+      "pgp" => "application/octet-stream",
+      "gpg" => "application/octet-stream",
+      "ai" => "application/pdf",
+      "asc" => "application/pgp-signature",
+      "rtf" => "application/rtf",
+      "spp" => "application/scvp-vp-response",
+      "sgml" => "application/sgml",
+      "curl" => "application/vnd.curl",
+      "odc" => "application/vnd.oasis.opendocument.chart",
+      "odf" => "application/vnd.oasis.opendocument.formula",
+      "odi" => "application/vnd.oasis.opendocument.image",
+      "bdm" => "application/vnd.syncml.dm+wbxml",
+      "dcr" => "application/x-director",
+      "exe" => "application/x-ms-dos-executable",
+      "wmz" => "application/x-ms-wmz",
+      "cmd" => "application/x-msdos-program",
+      "bat" => "application/x-msdos-program",
+      "com" => "application/x-msdos-program",
+      "reg" => "application/x-msdos-program",
+      "ps1" => "application/x-msdos-program",
+      "vbs" => "application/x-msdos-program",
+      "pm" => "application/x-pagemaker",
+      "xml" => "application/xml",
+      "dtd" => "application/xml-dtd",
+      "kar" => "audio/midi",
+      "mid" => "audio/midi",
+      "midi" => "audio/midi",
+      "m4a" => "audio/mp4",
+      "mp2" => "audio/mpeg",
+      "ogg" => "audio/ogg",
+      "wav" => "audio/wav",
+      "webm" => "audio/webm",
+      "wmv" => "audio/x-ms-wmv",
+      "ra" => "audio/x-pn-realaudio",
+      "hif" => "image/heic",
+      "sub" => "image/vnd.dvb.subtitle",
+      "xbm" => "image/x-xbitmap",
+      "mts" => "model/vnd.mts",
+      "rst" => "text/plain",
+    }
+
     def test_full_parity_with_mime_types
       exts = Set.new
       MIME::Types.each do |type|
         type.extensions.each { |ext| exts << ext }
       end
 
+      differences = []
+
       exts.each do |ext|
         types = MIME::Types.type_for("a.#{ext}")
 
@@ -73,8 +125,18 @@ def test_full_parity_with_mime_types
         #   puts "#{ext} Expected #{type.content_type} Got #{MiniMime.lookup_by_filename("a.#{ext}").content_type}"
         # end
 
-        assert_equal type.content_type, MiniMime.lookup_by_filename("a.#{ext}").content_type
+        expected = type.content_type
+        if WINDOWS_TYPES.key?(ext) && RUBY_PLATFORM.match?(/mingw|windows/i)
+          expected = WINDOWS_TYPES[ext]
+        end
+        actual = MiniMime.lookup_by_filename("a.#{ext}").content_type
+
+        if expected != actual
+          differences << %{Expected ".#{ext}" to return #{expected.inspect}, got: #{actual.inspect}}
+        end
       end
+
+      assert differences.empty?, differences.join("\n")
     end
   end
 end