Correct logic on value detection.

Author: dlongley

lib/expand.js

@@ -169,26 +169,21 @@ api.expand = ({
     (activeCtx.previousContext ? activeCtx : null);
   let keys = Object.keys(element).sort();
   let mustRevert = !insideIndex;
-  if(mustRevert && typeScopedContext && keys[0] !== '@context') {
-    // check if element is a subject reference
-    if(keys.length === 1) {
+  if(mustRevert && typeScopedContext && keys.length <= 2 &&
+    !keys.includes('@context')) {
+    for(const key of keys) {
       const expandedProperty = _expandIri(
-        typeScopedContext, keys[0], {vocab: true}, options);
-      if(expandedProperty === '@id') {
-        // subject reference found, do not revert
+        typeScopedContext, key, {vocab: true}, options);
+      if(expandedProperty === '@value') {
+        // value found, ensure type-scoped context is used to expand it
         mustRevert = false;
+        activeCtx = typeScopedContext;
+        break;
       }
-    } else if(keys.length <= 2) {
-      // check if element is a value
-      for(const key of keys) {
-        const expandedProperty = _expandIri(
-          typeScopedContext, key, {vocab: true}, options);
-        if(expandedProperty === '@value') {
-          // value found, ensure type-scoped context is used to expand it
-          mustRevert = false;
-          activeCtx = typeScopedContext;
-          break;
-        }
+      if(expandedProperty === '@id' && keys.length === 1) {
+        // subject reference found, do not revert
+        mustRevert = false;
+        break;
       }
     }
   }