Open package.toml file with UTF8 locale

CHANGES.md

@@ -10,6 +10,8 @@ To be released.
 
  -  The `uri` type has completly gone; use `url` instead.
     [[#126], [#281] by Jonghun Park]
+ -  Fixed locale to open package.toml.
+    [[#290], [#322]]
 
 ### Docs target
 
@@ -60,6 +62,7 @@ To be released.
 [#225]: https://github.com/nirum-lang/nirum/issues/225
 [#281]: https://github.com/nirum-lang/nirum/pull/281
 [#283]: https://github.com/spoqa/nirum/pull/283
+[#290]: https://github.com/nirum-lang/nirum/issues/290
 [#297]: https://github.com/nirum-lang/nirum/issues/297
 [#300]: https://github.com/nirum-lang/nirum/pull/300
 [#304]: https://github.com/nirum-lang/nirum/pull/304
@@ -68,6 +71,7 @@ To be released.
 [#311]: https://github.com/nirum-lang/nirum/pull/311
 [#318]: https://github.com/nirum-lang/nirum/pull/318
 [#321]: https://github.com/nirum-lang/nirum/pull/321
+[#322]: https://github.com/nirum-lang/nirum/pull/322
 [CommonMark]: http://commonmark.org/
 [table syntax extension]: https://github.github.com/gfm/#tables-extension-
 [special attributes extension]: https://michelf.ca/projects/php-markdown/extra/#spe-attr

src/Nirum/Package/Metadata.hs

@@ -65,6 +65,7 @@ import Data.Text (Text, append, snoc, unpack)
 import Data.Text.Encoding (encodeUtf8)
 import qualified Data.Text.IO as TIO
 import System.FilePath ((</>))
+import System.IO
 import Text.Email.Parser (EmailAddress)
 import qualified Text.Email.Validate as EV
 import Text.InterpolatedString.Perl6 (qq)
@@ -217,7 +218,9 @@ parseMetadata metadataPath' tomlText = do
 
 readMetadata :: Target t => FilePath -> IO (Either MetadataError (Metadata t))
 readMetadata metadataPath' = do
-    tomlText <- TIO.readFile metadataPath'
+    h <- openFile metadataPath' ReadMode
+    hSetEncoding h utf8
+    tomlText <- TIO.hGetContents h
     return $ parseMetadata metadataPath' tomlText
 
 metadataPath :: FilePath -> FilePath