From 8b0a398a82afdb0a03b24fd0a635b9894d8909fc Mon Sep 17 00:00:00 2001
From: Robert <rob@vllmrt.net>
Date: Sat, 11 Feb 2023 20:38:43 +0100
Subject: [PATCH] don't require email address for feeds (#736)

Use empty string rather than Maybe for backwards-compat

Co-authored-by: Jasper Van der Jeugt <m@jaspervdj.be>
---
 data/templates/atom.xml |  2 ++
 lib/Hakyll/Web/Feed.hs  | 11 ++++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/data/templates/atom.xml b/data/templates/atom.xml
index ef1faef57..1143a79e7 100644
--- a/data/templates/atom.xml
+++ b/data/templates/atom.xml
@@ -6,7 +6,9 @@
     <id>$root$$url$</id>
     <author>
         <name>$authorName$</name>
+        $if(authorEmail)$
         <email>$authorEmail$</email>
+        $endif$
     </author>
     <updated>$updated$</updated>
     $body$
diff --git a/lib/Hakyll/Web/Feed.hs b/lib/Hakyll/Web/Feed.hs
index 60a662c66..fd1516fcf 100644
--- a/lib/Hakyll/Web/Feed.hs
+++ b/lib/Hakyll/Web/Feed.hs
@@ -73,7 +73,8 @@ data FeedConfiguration = FeedConfiguration
       feedDescription :: String
     , -- | Name of the feed author.
       feedAuthorName  :: String
-    , -- | Email of the feed author.
+    , -- | Email of the feed author.  Set this to the empty String to leave out
+      -- the email address.
       feedAuthorEmail :: String
     , -- | Absolute root URL of the feed site (e.g. @http://jaspervdj.be@)
       feedRoot        :: String
@@ -102,7 +103,7 @@ renderFeed feedTpl itemTpl config itemContext items = do
         [ itemContext
         , constField "root" (feedRoot config)
         , constField "authorName"  (feedAuthorName config)
-        , constField "authorEmail" (feedAuthorEmail config)
+        , emailField
         ]
 
     feedContext = mconcat
@@ -110,7 +111,7 @@ renderFeed feedTpl itemTpl config itemContext items = do
          , constField "title"       (feedTitle config)
          , constField "description" (feedDescription config)
          , constField "authorName"  (feedAuthorName config)
-         , constField "authorEmail" (feedAuthorEmail config)
+         , emailField
          , constField "root"        (feedRoot config)
          , urlField   "url"
          , updatedField
@@ -125,6 +126,10 @@ renderFeed feedTpl itemTpl config itemContext items = do
             StringField s -> return s
             _             -> fail "Hakyll.Web.Feed.renderFeed: Internal error"
 
+    emailField = case feedAuthorEmail config of
+        ""    -> missingField
+        email -> constField "authorEmail" email
+
 --------------------------------------------------------------------------------
 -- | Render an RSS feed using given templates with a number of items.
 renderRssWithTemplates ::