fix(jruby): Schema#validate should not accumulate errors in @errors

Fixes #1282

CHANGELOG.md

@@ -103,6 +103,8 @@ end
 ### Fixed
 
 * [JRuby] Fix NPE in Schema parsing when an imported resource doesn't have a `systemId`. [[#2296](https://github.com/sparklemotion/nokogiri/issues/2296)] (Thanks, [@pepijnve](https://github.com/pepijnve)!)
+* [JRuby] Fix `Schema#validate` to only return the most recent Document's errors. Previously, if multiple documents were validated, this method returned the accumulated errors of all previous documents. [#1282]
+* [JRuby] Fix `Schema#validate` to not clobber the `@errors` instance variable. [#1282]
 
 
 ## 1.12.3 / 2021-08-10

ext/java/nokogiri/XmlSchema.java

@@ -212,7 +212,7 @@ public class XmlSchema extends RubyObject
  IRubyObject
  validate_document_or_file(ThreadContext context, XmlDocument xmlDocument)
  {
- RubyArray errors = (RubyArray) this.getInstanceVariable("@errors");
+ RubyArray errors = (RubyArray)context.runtime.newEmptyArray();
  ErrorHandler errorHandler = new SchemaErrorHandler(context.runtime, errors);
  setErrorHandler(errorHandler);
 

test/xml/test_schema.rb

@@ -231,6 +231,47 @@ def test_xsd_import_with_no_systemid
  Nokogiri::XML::Schema(xsd) # assert_nothing_raised
  end
 
+ describe "Schema#validate" do
+ let(:xsd) do
+ <<~EOF
+ <?xml version="1.0" encoding="UTF-8"?>
+ <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ targetNamespace="http://www.example.org/contactExample">
+ <xs:element name="Contacts"></xs:element>
+ </xs:schema>
+ EOF
+ end
+
+ let(:good_xml) { %Q(<Contacts xmlns="http://www.example.org/contactExample"><Contact></Contact></Contacts>) }
+ let(:bad_xml) { %Q(<Contacts xmlns="http://www.example.org/wrongNs"><Contact></Contact></Contacts>) }
+
+ it "does not clobber @errors" do
+ schema = Nokogiri::XML::Schema.new(xsd)
+ bad_doc = Nokogiri::XML(bad_xml)
+
+ # assert on setup
+ assert_empty(schema.errors)
+ refute_empty(schema.validate(bad_doc))
+
+ # this is the bit under test
+ assert_empty(schema.errors)
+ end
+
+ it "returns only the most recent document's errors" do
+ # https://github.com/sparklemotion/nokogiri/issues/1282
+ schema = Nokogiri::XML::Schema.new(xsd)
+ good_doc = Nokogiri::XML(good_xml)
+ bad_doc = Nokogiri::XML(bad_xml)
+
+ # assert on setup
+ assert_empty(schema.validate(good_doc))
+ refute_empty(schema.validate(bad_doc))
+
+ # this is the bit under test
+ assert_empty(schema.validate(good_doc))
+ end
+ end
+
  describe "CVE-2020-26247" do
  # https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-vr8q-g5c7-m54m
  let(:schema) do