Better error messages

hakyll.cabal

@@ -172,25 +172,26 @@ Library
     data-default         >= 0.4      && < 0.8,
     deepseq              >= 1.3      && < 1.5,
     directory            >= 1.0      && < 1.4,
+    file-embed           >= 0.0.10.1 && < 0.0.12,
     filepath             >= 1.0      && < 1.5,
     lrucache             >= 1.1.1    && < 1.3,
     mtl                  >= 1        && < 2.3,
     network-uri          >= 2.6      && < 2.7,
+    optparse-applicative >= 0.12     && < 0.15,
     parsec               >= 3.0      && < 3.2,
     process              >= 1.6      && < 1.7,
     random               >= 1.0      && < 1.2,
     regex-tdfa           >= 1.1      && < 1.3,
     resourcet            >= 1.1      && < 1.3,
     scientific           >= 0.3.4    && < 0.4,
     tagsoup              >= 0.13.1   && < 0.15,
+    template-haskell     >= 2.14     && < 2.15,
     text                 >= 0.11     && < 1.3,
     time                 >= 1.8      && < 1.10,
     time-locale-compat   >= 0.1      && < 0.2,
     unordered-containers >= 0.2      && < 0.3,
     vector               >= 0.11     && < 0.13,
-    yaml                 >= 0.8.11   && < 0.12,
-    optparse-applicative >= 0.12     && < 0.15,
-    file-embed           >= 0.0.10.1 && < 0.0.12
+    yaml                 >= 0.8.11   && < 0.12
 
   If flag(previewServer)
     Build-depends:

lib/Hakyll/Web/Feed.hs

@@ -1,5 +1,5 @@
-{-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TemplateHaskell   #-}
 
 --------------------------------------------------------------------------------
 -- | A Module that allows easy rendering of RSS feeds.
@@ -38,27 +38,25 @@ import           Hakyll.Web.Template.List
 
 
 --------------------------------------------------------------------------------
-import           Data.FileEmbed              (makeRelativeToProject, embedFile)
-import qualified Data.Text                   as T
-import qualified Data.Text.Encoding          as T
+import           Data.FileEmbed              (makeRelativeToProject)
 
 
 --------------------------------------------------------------------------------
 rssTemplate :: Template
-rssTemplate = readTemplate $ T.unpack $ T.decodeUtf8 $
-    $(makeRelativeToProject "data/templates/rss.xml" >>= embedFile)
+rssTemplate =
+    $(makeRelativeToProject "data/templates/rss.xml" >>= embedTemplate)
 
 rssItemTemplate :: Template
-rssItemTemplate = readTemplate $ T.unpack $ T.decodeUtf8 $
-    $(makeRelativeToProject "data/templates/rss-item.xml" >>= embedFile)
+rssItemTemplate =
+    $(makeRelativeToProject "data/templates/rss-item.xml" >>= embedTemplate)
 
 atomTemplate :: Template
-atomTemplate = readTemplate $ T.unpack $ T.decodeUtf8 $
-    $(makeRelativeToProject "data/templates/atom.xml" >>= embedFile)
+atomTemplate =
+    $(makeRelativeToProject "data/templates/atom.xml" >>= embedTemplate)
 
 atomItemTemplate :: Template
-atomItemTemplate = readTemplate $ T.unpack $ T.decodeUtf8 $
-    $(makeRelativeToProject "data/templates/atom-item.xml" >>= embedFile)
+atomItemTemplate =
+    $(makeRelativeToProject "data/templates/atom-item.xml" >>= embedTemplate)
 
 
 --------------------------------------------------------------------------------

lib/Hakyll/Web/Template.hs

@@ -138,6 +138,7 @@
 -- >     3...2...1
 -- > </p>
 --
+{-# LANGUAGE TemplateHaskell #-}
 module Hakyll.Web.Template
     ( Template
     , templateBodyCompiler
@@ -148,8 +149,30 @@ module Hakyll.Web.Template
     , readTemplate
     , compileTemplateItem
     , unsafeReadTemplateFile
+    , embedTemplate
     ) where
 
 
 --------------------------------------------------------------------------------
 import           Hakyll.Web.Template.Internal
+
+
+--------------------------------------------------------------------------------
+import           Data.FileEmbed               (embedFile)
+import qualified Data.Text                    as T
+import qualified Data.Text.Encoding           as T
+import           Language.Haskell.TH          (Exp, Q)
+
+
+--------------------------------------------------------------------------------
+-- | Embed template allows you embed a template within the Haskell binary.
+-- Example:
+--
+-- > myTemplate :: Template
+-- > myTemplate = $(embedTemplate "test.html")
+embedTemplate :: FilePath -> Q Exp
+embedTemplate filePath = [|
+    let source = T.unpack $ T.decodeUtf8 $(embedFile filePath) in
+    case parseTemplateElemsFile filePath source of
+        Left  err -> error err
+        Right tpl -> template filePath tpl |]

lib/Hakyll/Web/Template/Internal.hs

@@ -73,6 +73,7 @@ readTemplate :: String -> Template
 readTemplate = either error (template origin) . parseTemplateElemsFile origin
   where
     origin = "{literal}"
+{-# DEPRECATED readTemplate "Use templateCompiler instead" #-}
 
 --------------------------------------------------------------------------------
 -- | Parse an item body into a template.

tests/Hakyll/Web/Template/Tests.hs

@@ -1,16 +1,17 @@
 --------------------------------------------------------------------------------
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TemplateHaskell   #-}
 module Hakyll.Web.Template.Tests
     ( tests
     ) where
 
 
 --------------------------------------------------------------------------------
 import           Test.Tasty                   (TestTree, testGroup)
-import           Test.Tasty.HUnit             (Assertion, testCase, (@=?),
-                                               (@?=), assertBool)
+import           Test.Tasty.HUnit             (Assertion, assertBool, testCase,
+                                               (@=?), (@?=))
 
-import           Data.Either                    (isLeft)
+import           Data.Either                  (isLeft)
 
 --------------------------------------------------------------------------------
 import           Hakyll.Core.Compiler
@@ -83,6 +84,8 @@ tests = testGroup "Hakyll.Web.Template.Tests" $ concat
         , assertBool "did not fail to parse" $ isLeft $
           parse "$for(xs)$\n  <p>foo</p>\n$endif$"
         ]
+
+    , [testCase "embeddedTemplate" testEmbeddedTemplate]
     ]
   where
     parse = parseTemplateElemsFile ""
@@ -122,6 +125,8 @@ testApplyJoinTemplateList :: Assertion
 testApplyJoinTemplateList = do
     store    <- newTestStore
     provider <- newTestProvider store
+    tpl      <- testCompilerDone store provider "tpl" $
+        compileTemplateItem (Item "tpl" "<b>$body$</b>")
     str      <- testCompilerDone store provider "item3" $
         applyJoinTemplateList ", " tpl defaultContext [i1, i2]
 
@@ -130,4 +135,22 @@ testApplyJoinTemplateList = do
   where
     i1  = Item "item1" "Hello"
     i2  = Item "item2" "World"
-    tpl = readTemplate "<b>$body$</b>"
+
+
+--------------------------------------------------------------------------------
+embeddedTemplate :: Template
+embeddedTemplate = $(embedTemplate "tests/data/embed.html")
+
+--------------------------------------------------------------------------------
+testEmbeddedTemplate :: Assertion
+testEmbeddedTemplate = do
+    store    <- newTestStore
+    provider <- newTestProvider store
+    str      <- testCompilerDone store provider "item3" $
+        applyTemplate embeddedTemplate defaultContext item
+
+    itemBody str @?= "<p>Hello, world</p>\n"
+    cleanTestEnv
+  where
+    item = Item "item1" "Hello, world"
+

tests/data/embed.html

@@ -0,0 +1 @@
+<p>$body$</p>