From 89d90fbae24d42cb9d2975921daa607cbb586ffd Mon Sep 17 00:00:00 2001
From: Dave Longley <dlongley@digitalbazaar.com>
Date: Wed, 9 Jul 2014 15:16:24 -0400
Subject: [PATCH] Fix context caching bug.

- Update active context for each processed context to ensure
  the proper associations are made in the cache between an
  active context, the local context processed, and the result.
---
 jsonld.php | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/jsonld.php b/jsonld.php
index 454affd..c3454a2 100644
--- a/jsonld.php
+++ b/jsonld.php
@@ -2982,14 +2982,13 @@ class JsonLdProcessor {
       return self::_cloneActiveContext($active_ctx);
     }
 
-    // process each context in order
+    // process each context in order, update active context
+    // on each iteration to ensure proper caching
     $rval = $active_ctx;
-    $must_clone = true;
     foreach($ctxs as $ctx) {
       // reset to initial context
       if($ctx === null) {
-        $rval = $this->_getInitialContext($options);
-        $must_clone = false;
+        $rval = $active_ctx = $this->_getInitialContext($options);
         continue;
       }
 
@@ -3010,17 +3009,15 @@ class JsonLdProcessor {
       if(property_exists($jsonld_cache, 'activeCtx')) {
         $cached = $jsonld_cache->activeCtx->get($active_ctx, $ctx);
         if($cached) {
-          $rval = $cached;
+          $rval = $active_ctx = $cached;
           $must_clone = true;
           continue;
         }
       }
 
-      // clone context, if required, before updating
-      if($must_clone) {
-        $rval = self::_cloneActiveContext($rval);
-        $must_clone = false;
-      }
+      // update active context and clone new one before updating
+      $active_ctx = $rval;
+      $rval = self::_cloneActiveContext($rval);
 
       // define context mappings for keys in local context
       $defined = new stdClass();
@@ -4698,7 +4695,7 @@ class JsonLdProcessor {
       throw new JsonLdException(
         'Invalid JSON-LD syntax; keywords cannot be overridden.',
         'jsonld.SyntaxError', 'keyword redefinition',
-        array('context' => $local_ctx));
+        array('context' => $local_ctx, 'term' => $term));
     }
 
     // remove old mapping