Test for DOMParser slightly more complicated.

Skip HTML tests if there is  no DOMParser, or loading the module raises an exception.
Allows Karma tests to pass.

Author: gkellogg

lib/jsonld.js

@@ -997,7 +997,14 @@ jsonld.documentLoaders.xhr = require('./documentLoaders/xhr');
 
 // Optional DOM parser
 try {
-  jsonld.domParser = require('xmldom').DOMParser;
+  jsonld.domParser = require('xmldom').DOMParser || class NoDOMParser {
+    parseFromString() {
+      throw new JsonLdError(
+        'Could not parse HTML document. ' +
+        'HTML parsing not implemented.', 'jsonld.LoadDocumentError',
+        {code: 'loading document failed'});
+    }
+  };
 } catch(e) {
   jsonld.domParser = class NoDOMParser {
     parseFromString() {

tests/test-common.js

@@ -25,6 +25,15 @@ const manifest = options.manifest || {
   filename: '/'
 };
 
+let htmlSupport;
+try {
+  // xmldom may load but not have a DOMParser
+  htmlSupport = !!require('xmldom').DOMParser;
+} catch(e) {
+  htmlSupport = false;
+}
+console.log("HTML Support: " + htmlSupport);
+
 const TEST_TYPES = {
   'jld:CompactTest': {
     skip: {
@@ -533,6 +542,13 @@ function addTest(manifest, test, tests) {
         self.skip();
       }
 
+      // if xmldom not loaded, skip HTML tests
+      if(isJsonLdType(test, 'jld:HtmlTest') && !htmlSupport) {
+        console.log('Skipping test due to lack of HTML support:',
+          {id: test['@id'], name: test.name});
+        self.skip();
+      }
+
       // skip based on test type
       if(isJsonLdType(test, SKIP_TESTS)) {
         if(options.verboseSkip) {