From 098f95f3ed87807e30c4b37e311bc8336c099dca Mon Sep 17 00:00:00 2001
From: Conrad Irwin <conrad.irwin@gmail.com>
Date: Thu, 28 Jul 2011 01:36:24 -0700
Subject: [PATCH] Fail noisily on unfinished JSON prefixes...

---
 ext/yajl/yajl_ext.c          | 10 ++++++++++
 spec/parsing/one_off_spec.rb | 28 +++++++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/ext/yajl/yajl_ext.c b/ext/yajl/yajl_ext.c
index 44c0f7e3..a38d0c2f 100644
--- a/ext/yajl/yajl_ext.c
+++ b/ext/yajl/yajl_ext.c
@@ -474,6 +474,16 @@ static VALUE rb_yajl_parser_parse(int argc, VALUE * argv, VALUE self) {
         return Qnil;
     }
 
+    // Because we've overridden the yajl_parse_complete state of the parser to allow
+    // us to parse multiple objects out of one stream; we can't use it to determine
+    // whether we've parsed a single object. Instead we'll check whether we've successfully
+    // parsed a single token.
+    if (!RARRAY_LEN(wrapper->builderStack) ||
+            wrapper->nestedHashLevel ||
+            wrapper->nestedArrayLevel) {
+        rb_raise(cParseError, "unexpected end of JSON string");
+    }
+
     return rb_ary_pop(wrapper->builderStack);
 }
 
diff --git a/spec/parsing/one_off_spec.rb b/spec/parsing/one_off_spec.rb
index 3a0a3543..537e92d2 100644
--- a/spec/parsing/one_off_spec.rb
+++ b/spec/parsing/one_off_spec.rb
@@ -56,6 +56,32 @@
     output.should == {"key" => 1234}
   end
 
+  %w(
+    {"hi":
+    "worl
+    1.
+    tru
+    nu
+    [[[[[f
+    ["hey","babe"
+    [{"wtf...
+  ).each do |example|
+    it "should not parse #{example.inspect}" do
+      lambda {
+        Yajl::Parser.parse(example)
+      }.should raise_error "unexpected end of JSON string"
+    end
+  end
+
+  it "should not parse tails after incomplete heads" do
+      lambda {
+        Yajl::Parser.parse('{"hi":')
+      }.should raise_error
+      lambda {
+        Yajl::Parser.parse('"hi"}')
+      }.should raise_error
+  end
+
   it "should parse numbers greater than 2,147,483,648" do
     Yajl::Parser.parse("{\"id\": 2147483649}").should eql({"id" => 2147483649})
     Yajl::Parser.parse("{\"id\": 5687389800}").should eql({"id" => 5687389800})
@@ -78,4 +104,4 @@
       Yajl::Parser.parse('{"key": "value"}').values.first.encoding.should eql(Encoding.default_internal)
     end
   end
-end
\ No newline at end of file
+end