Fix type-scoped contexts breaking when aliasing @type

Closes #115

Author: jeswr

lib/JsonLdParser.ts

@@ -54,7 +54,7 @@ export class JsonLdParser extends Transform implements RDF.Sink<EventEmitter, RD
   // Jobs that are not started yet that process a @type (only used if streamingProfile is false)
   private readonly typeJobs: { job: () => Promise<void>, keys: string[] }[];
   // Jobs that are not started yet because of a missing @context or @type (only used if streamingProfile is false)
-  private readonly contextAwaitingJobs: { job: () => Promise<void>, keys: string[] }[];
+  private readonly contextAwaitingJobs: { job: () => Promise<void>, keys: string[]; depth: number }[];
 
   // The last depth that was processed.
   private lastDepth: number;
@@ -453,12 +453,8 @@ export class JsonLdParser extends Transform implements RDF.Sink<EventEmitter, RD
               jobs = this.contextJobs[depth] = [];
             }
             jobs.push(valueJobCb);
-          } else if (keys[depth] === '@type'
-            || typeof keys[depth] === 'number' && keys[depth - 1] === '@type') { // Also capture @type with array values
-            // Remove @type from keys, because we want it to apply to parent later on
-            this.typeJobs.push({ job: valueJobCb, keys: keys.slice(0, keys.length - 1) });
           } else {
-            this.contextAwaitingJobs.push({ job: valueJobCb, keys });
+            this.contextAwaitingJobs.push({ job: valueJobCb, keys, depth });
           }
         } else {
           // Make sure that our value jobs are chained synchronously
@@ -508,8 +504,20 @@ export class JsonLdParser extends Transform implements RDF.Sink<EventEmitter, RD
     // Clear the keyword cache.
     this.parsingContext.unaliasedKeywordCacheStack.splice(0);
 
-    // Handle non-context jobs
+    const contextAwaitingJobs: { job: () => Promise<void>, keys: string[]; depth: number }[] = [];
+
     for (const job of this.contextAwaitingJobs) {
+      if ((await this.util.unaliasKeyword(job.keys[job.depth], job.keys, job.depth, true)) === '@type'
+      || typeof job.keys[job.depth] === 'number' && (await this.util.unaliasKeyword(job.keys[job.depth - 1], job.keys, job.depth - 1, true)) === '@type') { // Also capture @type with array values
+        // Remove @type from keys, because we want it to apply to parent later on
+        this.typeJobs.push({ job: job.job, keys: job.keys.slice(0, job.keys.length - 1) })
+      } else {
+        contextAwaitingJobs.push(job)
+      }
+    }
+
+    // Handle non-context jobs
+    for (const job of contextAwaitingJobs) {
       // Check if we have a type (with possible type-scoped context) that should be handled before.
       // We check all possible parent nodes for the current job, from root to leaves.
       if (this.typeJobs.length > 0) {

test/JsonLdParser-test.ts

@@ -13523,4 +13523,30 @@ describe('JsonLdParser', () => {
       return expect(arrayifyStream(result)).rejects.toThrow(new Error('my error'));
     });
   });
+
+  it('should parse a VC with minified context', async () => {
+    const parser = new JsonLdParser();
+    const stream = streamifyString(JSON.stringify({
+      "@context": {
+        "ty": "@type",
+        "VerifiableCredential": {
+          "@id": "https://www.w3.org/2018/credentials#VerifiableCredential",
+          "@context": {
+            "credentialSubject": {"@id": "https://www.w3.org/2018/credentials#credentialSubject", "@type": "@id"},
+          }
+        },
+      },
+      "@id": "https://some.credential",
+      "credentialSubject": {
+        "@id": "https://some.requestor",
+      },
+      "ty": 
+        "VerifiableCredential"
+      
+    }));
+    return expect(await arrayifyStream(stream.pipe(parser))).toBeRdfIsomorphic([
+      DF.quad(DF.namedNode("https://some.credential"), DF.namedNode('https://www.w3.org/2018/credentials#credentialSubject'), DF.namedNode('https://some.requestor')),
+      DF.quad(DF.namedNode("https://some.credential"), DF.namedNode('http://www.w3.org/1999/02/22-rdf-syntax-ns#type'), DF.namedNode('https://www.w3.org/2018/credentials#VerifiableCredential')),
+    ]);
+  });
 });