In Reader.open, only use format to find a concrete reader, not other options. This allows the content-type and actual file content to be used to select a reader, in preference to filename and extensions.

Fixes #353.

Author: gkellogg

lib/rdf/reader.rb

@@ -180,8 +180,8 @@ class << self
     # @yieldreturn [void] ignored
     # @raise  [RDF::FormatError] if no reader found for the specified format
     def self.open(filename, format: nil, **options, &block)
-      # If we're the abstract reader, and we can figure out a concrete reader from format and options, use that.
-      if self == RDF::Reader && reader = self.for(format || {file_name: filename}.merge(options))
+      # If we're the abstract reader, and we can figure out a concrete reader from format, use that.
+      if self == RDF::Reader && format && reader = self.for(format)
         return reader.open(filename, format: format, **options, &block)
       end
 
@@ -383,7 +383,7 @@ def each_statement(&block)
       if block_given?
         begin
           loop { block.call(read_statement) }
-        rescue EOFError => e
+        rescue EOFError
           rewind rescue nil
         end
       end
@@ -417,7 +417,7 @@ def each_triple(&block)
       if block_given?
         begin
           loop { block.call(*read_triple) }
-        rescue EOFError => e
+        rescue EOFError
           rewind rescue nil
         end
       end

spec/reader_spec.rb

@@ -56,5 +56,20 @@
         reader_mock.got_here
       end
     end
+
+    it "uses content type in preference to file extension" do
+      uri = "http://example/foo.nq"
+      accept = (RDF::Format.accept_types + %w(*/*;q=0.1)).join(", ")
+      reader_mock = double("reader")
+      expect(reader_mock).to receive(:got_here)
+      WebMock.
+        stub_request(:get, uri).
+        to_return(body: "foo", status: 200, headers: { 'Content-Type' => 'text/turtle'})
+
+      described_class.open(uri) do |r|
+        expect(r).to be_a(RDF::Turtle::Reader)
+        reader_mock.got_here
+      end
+    end
   end
 end