null pointer exception in java extension

[tmm1]

repro:

require 'rubygems'
require 'nokogiri'

p [:version=, Nokogiri::VERSION]

doc = Nokogiri::HTML::DocumentFragment.parse('<p>this is a string.</p>')
nodes = doc.search('text()')
p nodes
p nodes.first.ancestors('pre, code')

mri:

ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10.5.0]
[:version=, "1.5.0.beta.4"]
[#<Nokogiri::XML::Text:0x80b601b8 "this is a string.">]
[]

jruby:

jruby 1.6.0 (ruby-1.8.7-p330) (2011-04-06 aa7d946) (Java HotSpot(TM) 64-Bit Server VM 1.6.0_24) [darwin-x86_64-java]
[:version=, "1.5.0.beta.4"]
[#<Nokogiri::XML::Text:0x7e4 "this is a string.">]
XmlNodeSet.java:184:in `include_p': java.lang.NullPointerException
  from XmlNodeSet$i$1$0$include_p.gen:65535:in `call'
  from CachingCallSite.java:282:in `cacheAndCall'
  from CachingCallSite.java:139:in `call'
  from CallOneArgNode.java:57:in `interpret'
  from NewlineNode.java:103:in `interpret'

[yokolet]

Thanks for giving reproducing sample code. I confirmed NPE was also raised on a master branch. I'll have a look.

[flavorjones]

Great catch. This appears to be a bug in NodeSet:

require 'rubygems'
require 'nokogiri'

p [:version=, Nokogiri::VERSION]

doc = Nokogiri::XML("<root></root>")
node_set = Nokogiri::XML::NodeSet.new(doc, [])
node_set.include?(doc.root)

results in

[:version=, "1.5.0.beta.4"]
XmlNodeSet.java:145:in `include_p': java.lang.NullPointerException
    from XmlNodeSet$i$1$0$include_p.gen:65535:in `call'
    from CachingCallSite.java:282:in `cacheAndCall'
    from CachingCallSite.java:139:in `call'
    from /home/mike/bar.rb:10:in `__file__'
    from /home/mike/bar.rb:-1:in `load'
    from Ruby.java:670:in `runScript'
    from Ruby.java:574:in `runNormally'
    from Ruby.java:423:in `runFromMain'
    from Main.java:278:in `doRunFromMain'
    from Main.java:198:in `internalRun'
    from Main.java:164:in `run'
    from Main.java:148:in `run'
    from Main.java:128:in `main'

[yokolet]

Fixed by rev. 407b582.

On master branch, the sample code printed as in below. So, the issue should be fixed.

[:version=, "1.5.0.beta.4"]
[#<Nokogiri::XML::Text:0x7ea "this is a string.">]
[]

[flavorjones]

(pure-java) making empty NodeSets with null nodes member safe to operate on. Closed by 694f885.

[tmm1]

👍 thanks

[tmm1]

I can't seem to figure out how to build a new java gem off of master. It keeps failing with:

rake aborted!
Don't know how to build task 'pkg/nokogiri-1.5.0.beta.4.1'

[tmm1]

diff --git a/Rakefile b/Rakefile
index 6e0c6a0..9937e14 100644
--- a/Rakefile
+++ b/Rakefile
@@ -80,11 +80,8 @@ if java
   end

   gem_build_path = File.join 'pkg', HOE.spec.full_name
-  # references to tgz_build_path are to work around a rake bug
-  tgz_build_path = File.join 'pkg', "#{HOE.spec.name}-#{HOE.spec.version}"

-  task gem_build_path => [:compile, tgz_build_path] do
-    cp_r tgz_build_path, gem_build_path, :verbose => true
+  task gem_build_path => :compile do
     cp 'lib/nokogiri/nokogiri.jar',
        File.join(gem_build_path, 'lib', 'nokogiri'),
        :verbose => true

[flavorjones]

Thanks. See 89056e7