Improve handling of file: scheme considering windows and Unix style p…

…aths.

lib/rdf/tabular/metadata.rb

@@ -142,7 +142,15 @@ def self.open(path, **options)
           'Accept' => 'application/ld+json, application/json'
         }
       )
-      path = "file:#{path}" if RDF::URI(path).relative?
+      if RDF::URI(path).relative?
+        path = File.expand_path(path, __FILE__)
+        if Gem.win_platform?
+          # Expanded path starts with drive letter
+          "file:/" + File.expand_path(path, __FILE__)
+        else
+          path = "file:#{File.expand_path(path, __FILE__)}"
+        end
+      end
       RDF::Util::File.open_file(path, **options) do |file|
         self.new(file, **options.merge(base: path, filenames: path))
       end

lib/rdf/tabular/reader.rb

@@ -80,7 +80,12 @@ def initialize(input = $stdin, **options, &block)
         @options[:base] ||= input.path if input.respond_to?(:path)
         @options[:base] ||= input.filename if input.respond_to?(:filename)
         if RDF::URI(@options[:base]).relative? && File.exist?(@options[:base].to_s)
-          file_uri = "file:" + File.expand_path(@options[:base])
+          file_uri = if Gem.win_platform?
+            # Expanded path starts with drive letter
+            "file:/" + File.expand_path(@options[:base], __FILE__)
+          else
+            "file:" + File.expand_path(@options[:base], __FILE__)
+          end
           @options[:base] = RDF::URI(file_uri.to_s).normalize
         end
 

spec/metadata_spec.rb

@@ -753,7 +753,7 @@
       context filename do
         subject {RDF::Tabular::Metadata.open(filename, logger: logger)}
         it {is_expected.to be_valid}
-        its(:filenames) {is_expected.to include("file:#{filename}")}
+        its(:filenames) {is_expected.to include("file:/#{filename.sub(/^\//, '')}")}
       end
       after(:each) do
         expect(logger.to_s).not_to match(/ERROR|WARN/)
@@ -818,7 +818,7 @@
             subject.validate
             expect(logger.to_s).to be_empty
           end
-          its(:filenames) {is_expected.to include("file:#{filename}")}
+          its(:filenames) {is_expected.to include("file:/#{filename.sub(/^\//, '')}")}
         end
       end
     end