feat(Git): Add support for plain changelogs (No external hosting)

src/Shift/CLI.hs

@@ -18,7 +18,7 @@ data ShiftOptions = ShiftOptions
 
 data ShiftCommand = GenerateCommand deriving (Show, Eq, Enum)
 
-data HostingType = GitHubType deriving (Show, Eq, Enum)
+data HostingType = GitHubType | GitType deriving (Show, Eq, Enum)
 
 shiftOptions :: Parser ShiftOptions
 shiftOptions = ShiftOptions
@@ -55,6 +55,7 @@ shiftCommand = subparser $
 hostingType :: ReadM HostingType
 hostingType = eitherReader $ \case
   "github" -> Right GitHubType
+  "git" -> Right GitType
   x -> Left $ "`" ++ x ++ "` is not a supported hosting type"
 
 makeLenses ''ShiftOptions

src/Shift/Git.hs

@@ -57,6 +57,9 @@ tempMain opts = withRepo ".git" $ \repo -> do
       runReaderT
         (void $ runStateT (mapM_ (renderDiff repo) pairedTags) state)
         opts
+    GitType -> runReaderT
+      (void $ runStateT (mapM_ (renderDiff repo) pairedTags) GitClientState)
+      opts
 
   where
     initGitHubState = do

src/Shift/Types.hs

@@ -18,11 +18,12 @@ import           Control.Monad.State     (MonadState, StateT, gets)
 import           Control.Monad.Trans     (liftIO)
 import           Data.Default            (Default, def)
 import           Data.Git                (Commit, Person, Ref, RefName,
-                                          personEmail)
+                                          personEmail, personName)
 import           Data.HashMap.Strict     (HashMap, insert, lookup)
 import           Data.HashSet            (HashSet)
 import           Data.String.Conversions (cs)
 import           Data.Text               (Text)
+import qualified Data.Text               as T
 import qualified Data.Vector             as V
 import           Data.Versions           (Versioning)
 import           GitHub                  (executeRequestWithMgr)
@@ -77,7 +78,6 @@ data BreakingChange = BreakingChange
   , _bcBody    :: Text
   } deriving (Show)
 
-
 data ConventionalCommit = ConventionalCommit
   { _ccType            :: CommitType
   , _ccScope           :: Text
@@ -145,6 +145,15 @@ instance Default RepositoryCache where
 
 makeClassy ''RepositoryCache
 
+data GitClientState = GitClientState
+
+instance ClientState GitClientState where
+  getRefURL _ = pure Nothing
+  getAuthorInfo person = pure . Just $
+    ( cs $ personName person
+    , mconcat ["mailto://", cs $ personEmail person]
+    )
+
 data GitHubClientState = GitHubClientState
   { _gcsCache      :: RepositoryCache
   , _gcsAuth       :: Auth