Merge pull request #21 from quasibit/issue/20/filter-duplicated-items

Issue/20/filter duplicated items

.gitattributes

@@ -0,0 +1 @@
+*.js eol=lf

examples/pagination/posts.njk

@@ -3,6 +3,7 @@ pagination:
   data: posts
   size: 1
   alias: post
+  addAllPagesToCollections: true
 permalink: "{{ post.url }}/"
 ---
 

src/isDuplicated.js

@@ -0,0 +1,16 @@
+"use strict";
+
+module.exports = (item, index, collection) => {
+  if (!collection) {
+    return false;
+  }
+
+  const notFoundIndex = -1;
+  const firstIndex = collection.findIndex((other) => other.url === item.url);
+
+  if (firstIndex === notFoundIndex) {
+    return false;
+  }
+
+  return index !== firstIndex;
+};

src/isIgnored.js

@@ -0,0 +1,5 @@
+"use strict";
+
+const sitemapProperty = require("./sitemapProperty");
+
+module.exports = (item) => sitemapProperty(item, "ignore") || !item.url;

src/sitemapItems.js

@@ -1,11 +1,15 @@
 "use strict";
 
+const isIgnored = require("./isIgnored");
+const isDuplicated = require("./isDuplicated");
 const paginationItems = require("./paginationItems");
 const sitemapItem = require("./sitemapItem");
-const sitemapProperty = require("./sitemapProperty");
 
 module.exports = (items, options) =>
   items
     .flatMap(paginationItems)
-    .filter((item) => !sitemapProperty(item, "ignore") && item.url)
+    .filter(
+      (item, index, collection) =>
+        !isIgnored(item) && !isDuplicated(item, index, collection)
+    )
     .map((item) => sitemapItem(item, options));