Add expansion warnings events.

- Add 'relateive IRI after expansion' warning event.
- Add 'invalid property expansion' warning event.
- Update tests to check call counts.

Author: davidlehn

lib/context.js

@@ -1078,7 +1078,6 @@ function _expandIri(activeCtx, value, relativeTo, localCtx, defined, options) {
         activeCtx,
         options
       });
-
     }
     if(expansionMapResult !== undefined) {
       value = expansionMapResult;
@@ -1144,6 +1143,18 @@ function _expandIri(activeCtx, value, relativeTo, localCtx, defined, options) {
     });
     if(expandedResult !== undefined) {
       value = expandedResult;
+    } else {
+      _handleEvent({
+        event: {
+          code: 'relative IRI after expansion',
+          level: 'warning',
+          message: 'Expansion resulted in a relative IRI.',
+          details: {
+            value
+          }
+        },
+        options
+      });
     }
   }
 

lib/expand.js

@@ -464,6 +464,18 @@ async function _expandObject({
         expandedParent
       });
       if(expandedProperty === undefined) {
+        _handleEvent({
+          event: {
+            code: 'invalid property expansion',
+            level: 'warning',
+            message: 'Invalid expansion for property.',
+            details: {
+              // FIXME: include expandedProperty before mapping
+              property: key
+            }
+          },
+          options
+        });
         continue;
       }
     }