Fix deprecation warning from legacy node url module

lib/utils.js

@@ -1,4 +1,4 @@
-var URL = require('url')
+var WHATWGURL = require('url').URL
   , namespaces = require('./namespaces')
   ;
 
@@ -55,13 +55,18 @@ function safeTrim (val) {
 exports.safeTrim = safeTrim;
 
 /*
- * Expose require('url').resolve, safely returning if either parameter
- * isn't provided
+ * Resolve a URL against a base URL, returning the original pathUrl if
+ * either parameter isn't provided or if the URL is not resolvable (e.g.
+ * tag: URIs and other non-http schemes that the URL constructor rejects).
  * @private
  */
 function resolve (baseUrl, pathUrl) {
   if (!baseUrl || !pathUrl) return pathUrl;
-  return URL.resolve(baseUrl, pathUrl);
+  try {
+    return new WHATWGURL(pathUrl, baseUrl).href;
+  } catch (e) {
+    return pathUrl;
+  }
 }
 exports.resolve = resolve;
 
@@ -72,8 +77,11 @@ exports.resolve = resolve;
  */
 function isAbsoluteUrl (uri) {
   if (!uri || typeof uri !== 'string') return false;
-  var parts = URL.parse(uri);
-  return Boolean(parts.host);
+  try {
+    return Boolean(new WHATWGURL(uri).host);
+  } catch (e) {
+    return false;
+  }
 }
 exports.isAbsoluteUrl = isAbsoluteUrl;
 
@@ -130,22 +138,22 @@ function reresolve (node, baseurl) {
         if (level[el].constructor.name === 'Object') {
           if (el == 'logo' || el == 'icon' || el == 'link') {
             if ('#' in level[el]) {
-              level[el]['#'] = URL.resolve(baseurl, level[el]['#']);
+              level[el]['#'] = resolve(baseurl, level[el]['#']);
             }
           } else if (el == 'image') {
             if ('url' in level[el] && level[el]['url'].constructor.name === 'Object' && '#' in level[el]['url']) {
-              level[el]['url']['#'] = URL.resolve(baseurl, level[el]['url']['#']);
+              level[el]['url']['#'] = resolve(baseurl, level[el]['url']['#']);
             }
             if ('link' in level[el] && level[el]['link'].constructor.name === 'Object' && '#' in level[el]['link']) {
-              level[el]['link']['#'] = URL.resolve(baseurl, level[el]['link']['#']);
+              level[el]['link']['#'] = resolve(baseurl, level[el]['link']['#']);
             }
           }
           if ('@' in level[el]) {
             var attrs = Object.keys(level[el]['@']);
             attrs.forEach(function (name) {
               if (name == 'href' || name == 'src' || name == 'uri') {
                 if ('string' === typeof level[el]['@'][name]) {
-                  level[el]['@'][name] = URL.resolve(baseurl, level[el]['@'][name]);
+                  level[el]['@'][name] = resolve(baseurl, level[el]['@'][name]);
                 }
               }
             });

test/feeds/atom-with-tag-uri-links.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0"?>
+<feed xmlns="http://www.w3.org/2005/Atom">
+  <title>Test Feed</title>
+  <link rel="self" href="http://example.com" />
+  <entry>
+    <title>Test Entry</title>
+    <link href="tag:mefi.social,2024-01-26:objectId=20368395" />
+    <id>tag:mefi.social,2024-01-26:objectId=20368395</id>
+  </entry>
+</feed>

test/link.js

@@ -15,4 +15,36 @@ describe('links', function(){
       });
   });
 
+  it('should not throw or emit a deprecation warning for tag: URI links (issue #295)', function (done) {
+    var tagUriFeed = __dirname + '/feeds/atom-with-tag-uri-links.xml';
+    var items = [];
+    var sawDeprecation = false;
+    var origEmit = process.emit;
+    process.emit = function(event, warning) {
+      if (event === 'warning' && warning && warning.name === 'DeprecationWarning') {
+        sawDeprecation = true;
+      }
+      return origEmit.apply(process, arguments);
+    };
+    fs.createReadStream(tagUriFeed).pipe(new FeedParser())
+      .on('readable', function () {
+        var stream = this, item;
+        while ((item = stream.read()) !== null) {
+          items.push(item);
+        }
+      })
+      .on('end', function () {
+        process.emit = origEmit;
+        assert.equal(items.length, 1);
+        assert.equal(items[0].link, 'tag:mefi.social,2024-01-26:objectId=20368395');
+        assert.equal(sawDeprecation, false, 'Should not emit a DEP0170 deprecation warning');
+        done();
+      })
+      .on('error', function (err) {
+        process.emit = origEmit;
+        assert.ifError(err);
+        done(err);
+      });
+  });
+
 });