Check for invalid values of @embed.

Author: gkellogg

CHANGELOG.md

@@ -35,6 +35,7 @@
 - Support for RDF transformation of `@direction` when `rdfDirection` is
   'i18n-datatype'.
 - Top level `@graph` omitted if `omitGraph` is `true`. 
+- Check for invalid values of `@embed`.
 
 ## 2.0.2 - 2020-01-17
 

lib/frame.js

@@ -118,6 +118,13 @@ api.frame = (state, subjects, frame, parent, property = null) => {
     }
     state.link[id] = output;
 
+    // validate @embed
+    if((flags.embed === '@first' || flags.embed === '@last') && state.is11) {
+      throw new JsonLdError(
+        'Invalid JSON-LD syntax; invalid value of @embed.',
+        'jsonld.SyntaxError', {code: 'invalid @embed value', frame: frame});
+    }
+
     // if embed is @never or if a circular reference would be created by an
     // embed, the subject cannot be embedded, just add the reference;
     // note that a circular reference won't occur when the embed flag is
@@ -346,11 +353,15 @@ function _getFrameFlag(frame, options, name) {
     // true => "@last"
     // false => "@never"
     if(rval === true) {
-      rval = '@last';
+      rval = '@once';
     } else if(rval === false) {
       rval = '@never';
-    } else if(rval !== '@always' && rval !== '@never' && rval !== '@link') {
-      rval = '@last';
+    } else if(rval !== '@always' && rval !== '@never' && rval !== '@link' &&
+              rval !== '@first' && rval !== '@last' && rval !== '@once')
+    {
+      throw new JsonLdError(
+        'Invalid JSON-LD syntax; invalid value of @embed.',
+        'jsonld.SyntaxError', {code: 'invalid @embed value', frame: frame});
     }
   }
   return rval;

lib/jsonld.js

@@ -475,12 +475,6 @@ jsonld.frame = async function(input, frame, options) {
   if(!options.hasOwnProperty('pruneBlankNodeIdentifiers')) {
     options.pruneBlankNodeIdentifiers = _processingMode(activeCtx, 1.1);
   }
-  if((options.embed === '@first' || options.embed === '@last') &&
-    _processingMode(activeCtx, 1.1))
-  {
-    console.warn(`WARNING: ${options.embed} is not a valid value ` +
-      `of @embed in 1.1 mode.`);
-  }
 
   // expand input
   const expanded = await jsonld.expand(input, options);
@@ -496,6 +490,8 @@ jsonld.frame = async function(input, frame, options) {
   const frameKeys = Object.keys(frame)
     .map(key => _expandIri(activeCtx, key, {vocab: true}));
   opts.merged = !frameKeys.includes('@graph');
+  opts.is11 = _processingMode(activeCtx, 1.1);
+
   // do framing
   const framed = _frameMergedOrDefault(expanded, expandedFrame, opts);
 

tests/test-common.js

@@ -170,8 +170,6 @@ const TEST_TYPES = {
         // blank nodes
         /frame-manifest.jsonld#t0052$/,
         /frame-manifest.jsonld#t0053$/,
-        // embed
-        /frame-manifest.jsonld#t0054$/,
         // lists
         /frame-manifest.jsonld#t0055$/,
         /frame-manifest.jsonld#t0058$/,