Fix handling of mixed types of first comment

When rd-style and hash-style comments are adjacent at the top of a file
Parser::Ruby#collect_first_comment would merge them together.  This
would lead to incorrect normalization of the comment.

Now RDoc detects the mixing and uses the first comment type only.

Fixes #266

Author: drbrain

History.rdoc

@@ -3,6 +3,8 @@
 * Bug fixes
   * Fixed reporting of undocumented method parameters when including when
     yield and &block are present.  Pull request #281 by Victor Bilyk.
+  * Fixed merging of rd-style and hash-style comments at the top of a file.
+    Bug #266 by Zachary Scott.
   * Removed duplicated condition in superclass fixup.  Pull request #282 by
     Benoit Daloze.
 

lib/rdoc/parser/ruby.rb

@@ -226,6 +226,7 @@ def collect_first_comment
     comment = ''
     comment.force_encoding @encoding if @encoding
     first_line = true
+    first_comment_tk_class = nil
 
     tk = get_tk
 
@@ -238,6 +239,9 @@ def collect_first_comment
         skip_tkspace
         tk = get_tk
       else
+        break if first_comment_tk_class and not first_comment_tk_class === tk
+        first_comment_tk_class = tk.class
+
         first_line = false
         comment << tk.text << "\n"
         tk = get_tk

test/test_rdoc_parser_ruby.rb

@@ -63,6 +63,21 @@ class C; end
     assert_equal Encoding::CP852, comment.text.encoding
   end
 
+  def test_collect_first_comment_rd_hash
+    parser = util_parser <<-CONTENT
+=begin
+first
+=end
+
+# second
+class C; end
+    CONTENT
+
+    comment = parser.collect_first_comment
+
+    assert_equal RDoc::Comment.new("first\n\n", @top_level), comment
+  end
+
   def test_get_class_or_module
     ctxt = RDoc::Context.new
     ctxt.store = @store