Add FilterArray class to Banzairs-filter-array

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/banzai/filter_array.rb b/lib/banzai/filter_array.rb
new file mode 100644
index 00000000000..77835a14027
--- /dev/null
+++ b/lib/banzai/filter_array.rb
@@ -0,0 +1,27 @@
+module Banzai
+  class FilterArray < Array
+    # Insert a value immediately after another value
+    #
+    # If the preceding value does not exist, the new value is added to the end
+    # of the Array.
+    def insert_after(after_value, value)
+      i = index(after_value) || length - 1
+
+      insert(i + 1, value)
+    end
+
+    # Insert a value immediately before another value
+    #
+    # If the succeeding value does not exist, the new value is added to the
+    # beginning of the Array.
+    def insert_before(before_value, value)
+      i = index(before_value) || -1
+
+      if i < 0
+        unshift(value)
+      else
+        insert(i, value)
+      end
+    end
+  end
+end