Fix handling of prefixed @vocab

Author: rubensworks

lib/ContextParser.ts

@@ -780,11 +780,17 @@ must be one of ${Util.CONTAINERS.join(', ')}`, ERROR_CODES.INVALID_CONTAINER_MAP
       // Parse inner contexts with minimal processing
       await this.parseInnerContexts(newContext, options);
 
-      // In JSON-LD 1.1, @vocab can be relative to @vocab in the parent context.
+      // In JSON-LD 1.1, @vocab can be relative to @vocab in the parent context, or a compact IRI.
       if ((newContext && newContext['@version'] || ContextParser.DEFAULT_PROCESSING_MODE) >= 1.1
-        && ((context['@vocab'] && typeof context['@vocab'] === 'string') || context['@vocab'] === '')
-        && context['@vocab'].indexOf(':') < 0 && parentContext && '@vocab' in parentContext) {
-        newContext['@vocab'] = parentContext['@vocab'] + context['@vocab'];
+        && ((context['@vocab'] && typeof context['@vocab'] === 'string') || context['@vocab'] === '')) {
+        if (parentContext && '@vocab' in parentContext && context['@vocab'].indexOf(':') < 0) {
+          newContext['@vocab'] = parentContext['@vocab'] + context['@vocab'];
+        } else {
+          if (Util.isCompactIri(context['@vocab']) || context['@vocab'] in newContextWrapped.getContextRaw()) {
+            // @vocab is a compact IRI or refers exactly to a prefix
+            newContext['@vocab'] = newContextWrapped.expandTerm(context['@vocab'], true);
+          }
+        }
       }
 
       // Handle terms (before protection checks)

test/ContextParser-test.ts

@@ -2043,6 +2043,36 @@ Tried mapping @id to {}`, ERROR_CODES.KEYWORD_REDEFINITION));
           }));
       });
 
+      it('should parse compact @vocab in 1.1', () => {
+        return expect(parser.parse({ '@vocab': 'ex:vocab/', '@version': 1.1, ex: {
+          '@id': 'http://example.org/',
+          '@prefix': true
+        }}, {}))
+          .resolves.toEqual(new JsonLdContextNormalized({
+            '@version': 1.1,
+            '@vocab': 'http://example.org/vocab/',
+            ex: {
+              '@id': 'http://example.org/',
+              '@prefix': true
+            },
+          }));
+      });
+
+      it('should parse compact @vocab in 1.1 that equals a prefix', () => {
+        return expect(parser.parse({ '@vocab': 'ex', '@version': 1.1, ex: {
+          '@id': 'http://example.org/',
+          '@prefix': true
+        }}, {}))
+          .resolves.toEqual(new JsonLdContextNormalized({
+            '@version': 1.1,
+            '@vocab': 'http://example.org/',
+            ex: {
+              '@id': 'http://example.org/',
+              '@prefix': true
+            },
+          }));
+      });
+
       it('should not expand @type in @container: @type', () => {
         return expect(parser.parse({
           '@base': 'http://example.org/base/',

test/JsonLdContextNormalized-test.ts

@@ -30,6 +30,16 @@ describe('JsonLdContextNormalized', () => {
         expect(context.expandTerm('def:123', true)).toBe('def:123');
       });
 
+      it('to return when it is a prefix', async () => {
+        const context = new JsonLdContextNormalized({def: 'http://DEF/'});
+        expect(context.expandTerm('def', true)).toBe('http://DEF/');
+      });
+
+      it('to return when it is a prefix with colon', async () => {
+        const context = new JsonLdContextNormalized({def: 'DEF/'});
+        expect(context.expandTerm('def:', true)).toBe('DEF/');
+      });
+
       it('to return when a direct value applies', async () => {
         const context = new JsonLdContextNormalized({abc: 'http://DEF'});
         expect(context.expandTerm('abc', true)).toBe('http://DEF');
@@ -647,6 +657,11 @@ describe('JsonLdContextNormalized', () => {
         expect(context.expandTerm('def:123', false)).toBe('def:123');
       });
 
+      it('to return when it is a prefix with colon', async () => {
+        const context = new JsonLdContextNormalized({def: 'DEF/'});
+        expect(context.expandTerm('def:', false)).toBe('DEF/');
+      });
+
       it('to return when a direct value applies, but ignore it in base-mode', async () => {
         const context = new JsonLdContextNormalized({abc: 'DEF'});
         expect(context.expandTerm('abc', false)).toBe('abc');