X-Git-Url: http://git.squeep.com/?a=blobdiff_plain;f=lib%2Fcommon.js;h=dc0585471303780c5720ab0d5f62fdf55d11d059;hb=dca6a761e6fe437a3fbeb24540bb6fa5d0b8eb12;hp=cfdf9db7e5c47feda5e05b52624a17a25949d853;hpb=1c4bb7e3bbdc1121ceba373c5be4459521197155;p=squeep-indieauth-helper

diff --git a/lib/common.js b/lib/common.js
index cfdf9db..dc05854 100644
--- a/lib/common.js
+++ b/lib/common.js
@@ -64,9 +64,44 @@ const pick = (obj, props) => {
 };
 
 
+/**
+ * Return a set containing non-shared items between two sets.
+ * @param {Set} a
+ * @param {Set} b
+ * @returns {Set}
+ */
+const setSymmetricDifference = (a, b) => {
+  const d = new Set(a);
+  for (const x of b) {
+    if (d.has(x)) {
+      d.delete(x);
+    } else {
+      d.add(x);
+    }
+  }
+  return d;
+};
+
+
+/**
+ * URL objects have weird names.
+ * @param {String} component
+ * @returns {String}
+ */
+const properURLComponentName = (component) => {
+  // eslint-disable-next-line security/detect-object-injection
+  return {
+    hash: 'fragment',
+    protocol: 'scheme',
+  }[component] || component;
+}
+
+
 module.exports = {
   fileScope,
   axiosResponseLogData,
   logTruncate,
   pick,
+  setSymmetricDifference,
+  properURLComponentName,
 };
\ No newline at end of file