rdoc: --extension option fix

* lib/rdoc/parser.rb (RDoc.alias_extension): a real file is irrelevant
  to aliasing.  [ruby-core:44796][Bug #6392]
* lib/rdoc/parser.rb (RDoc.zip?): non-existent file will not be a zip
  file.
* lib/rdoc/parser.rb (RDoc.can_parse_by_name): accept aliased
  extension file names.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@35532 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 16 insertions, 0 deletions

diff --git a/test/rdoc/test_rdoc_options.rb b/test/rdoc/test_rdoc_options.rb
index 763f50b5f0..2f74f45b45 100644
--- a/test/rdoc/test_rdoc_options.rb
+++ b/test/rdoc/test_rdoc_options.rb
@@ -337,6 +337,15 @@ file 'unreadable' not readable
     $LOAD_PATH.replace orig_LOAD_PATH
   end
 
+  def test_parse_extension_alias
+    out, err = capture_io do
+      @options.parse %w[--extension foobar=rdoc]
+    end
+
+    assert_empty out
+    assert_empty err
+  end
+
   def test_setup_generator
     test_generator = Class.new do
       def self.setup_options op
diff --git a/test/rdoc/test_rdoc_parser.rb b/test/rdoc/test_rdoc_parser.rb
index 37d3b67323..49e845e27b 100644
--- a/test/rdoc/test_rdoc_parser.rb
+++ b/test/rdoc/test_rdoc_parser.rb
@@ -57,6 +57,13 @@ class TestRDocParser < MiniTest::Unit::TestCase
 
     readme_file_name = File.expand_path '../README', __FILE__
     assert_equal @RP::Simple, @RP.can_parse(readme_file_name)
+
+    jtest_largerdoc_file_name = File.expand_path '../test.ja.largedoc', __FILE__
+    assert_nil @RP.can_parse(jtest_largerdoc_file_name)
+
+    @RP.alias_extension("rdoc", "largedoc")
+    assert_equal @RP::Simple, @RP.can_parse(jtest_largerdoc_file_name)
+
   end
 
   ##