From 52ac75b484408bc47bf31d7c10dbcb8c3a9024e8 Mon Sep 17 00:00:00 2001
From: jekyllbot <jekyllbot@users.noreply.github.com>
Date: Tue, 4 Apr 2017 19:47:11 -0400
Subject: [PATCH] Date filters should never raise an exception (#5722)

Merge pull request 5722
---
 lib/jekyll/filters.rb | 3 +++
 test/test_filters.rb  | 8 +++-----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/lib/jekyll/filters.rb b/lib/jekyll/filters.rb
index ea0fc905..c8da0e52 100644
--- a/lib/jekyll/filters.rb
+++ b/lib/jekyll/filters.rb
@@ -80,6 +80,7 @@ module Jekyll
     #
     # Returns the formatted String.
     def date_to_long_string(date)
+      return date if date.to_s.empty?
       time(date).strftime("%d %B %Y")
     end
 
@@ -94,6 +95,7 @@ module Jekyll
     #
     # Returns the formatted String.
     def date_to_xmlschema(date)
+      return date if date.to_s.empty?
       time(date).xmlschema
     end
 
@@ -108,6 +110,7 @@ module Jekyll
     #
     # Returns the formatted String.
     def date_to_rfc822(date)
+      return date if date.to_s.empty?
       time(date).rfc822
     end
 
diff --git a/test/test_filters.rb b/test/test_filters.rb
index 782b5be9..9e35df92 100644
--- a/test/test_filters.rb
+++ b/test/test_filters.rb
@@ -284,11 +284,9 @@ class TestFilters < JekyllUnitTest
       end
 
       context "without input" do
-        should "raise an error if input is nil" do
-          err = assert_raises Jekyll::Errors::InvalidDateError do
-            @filter.date_to_xmlschema(nil)
-          end
-          assert_equal "Invalid Date: 'nil' is not a valid datetime.", err.message
+        should "return input" do
+          assert_nil(@filter.date_to_xmlschema(nil))
+          assert_equal("", @filter.date_to_xmlschema(""))
         end
       end
     end