Update to lts-12.10, support ghc 8.4, and aeson 1.3.

Don't fully understand the need for the MonoLocalBinds language extension,
which was not needed before but now ghc complains if it's not included,
but I've tested it and it does work.

All the rest of the changes are straightforward AMP changes and dep
updates.

Removed fgl from stack.yaml because it seems that indirect dep no longer
needs to be specified for stack to build.

Added custom-setup stanza since stack now warns without one.

This commit was sponsored by Trenton Cronholm on Patreon.

14 files changed, 35 insertions, 17 deletions

diff --git a/CHANGELOG b/CHANGELOG
index c4f2857..d80372c 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,6 @@
-debug-me (1.20170811) UNRELEASED; urgency=medium
+debug-me (1.20181208) UNRELEASED; urgency=medium
 
-  * stack.yaml: Update to lts-11.17.
+  * Update to lts-12.10, support ghc 8.4, and aeson 1.3.
 
  -- Joey Hess <id@joeyh.name>  Tue, 10 Jul 2018 13:28:50 -0400
 
diff --git a/CmdLine.hs b/CmdLine.hs
index 2a64b6c..28227d4 100644
--- a/CmdLine.hs
+++ b/CmdLine.hs
@@ -8,7 +8,6 @@ module CmdLine where
 import Types
 import ServerList
 
-import Data.Monoid
 import Options.Applicative
 import Network.URI
 import Network.Wai.Handler.Warp (Port)
diff --git a/Crypto.hs b/Crypto.hs
index 2fe27e0..af3ad17 100644
--- a/Crypto.hs
+++ b/Crypto.hs
@@ -16,6 +16,7 @@ import Crypto.Error
 import Crypto.Random.Entropy
 import Data.ByteArray (convert)
 import qualified Data.ByteString as B
+import qualified Data.Semigroup as Sem
 
 dummySignature :: Signature
 dummySignature = OtherSignature (Val mempty)
@@ -78,10 +79,13 @@ mkSigVerifier (PublicKey (Val pk)) =
 		CryptoPassed pk' -> SigVerifier 1 (Ed25519.verify pk')
 		CryptoFailed _ -> mempty
 
+instance Sem.Semigroup SigVerifier where
+	SigVerifier na a <> SigVerifier nb b =
+		SigVerifier (na+nb) $ \d s -> b d s || a d s
+
 instance Monoid SigVerifier where
 	mempty = SigVerifier 0 $ \_b _s -> False
-	mappend (SigVerifier na a) (SigVerifier nb b) =
-		SigVerifier (na+nb) $ \d s -> b d s || a d s
+	mappend = (Sem.<>)
 
 data MySessionKey = MySessionKey Ed25519.SecretKey Ed25519.PublicKey
 
diff --git a/Graphviz.hs b/Graphviz.hs
index f8f165c..abbb93a 100644
--- a/Graphviz.hs
+++ b/Graphviz.hs
@@ -12,7 +12,6 @@ import CmdLine
 import Log
 
 import Data.Char hiding (Control)
-import Data.Monoid
 import Data.GraphViz
 import Data.GraphViz.Attributes.Complete
 import Data.GraphViz.Types.Generalised as G
@@ -23,6 +22,8 @@ import qualified Data.ByteString.Lazy as L
 import qualified Data.Text.Lazy as T
 import qualified Data.Text.Lazy.Encoding as T
 import Data.Text.Encoding.Error
+import Data.Monoid
+import Prelude
 
 graphviz :: GraphvizOpts -> IO ()
 graphviz opts = do
diff --git a/ProtocolBuffers.hs b/ProtocolBuffers.hs
index e87a156..d7c7799 100644
--- a/ProtocolBuffers.hs
+++ b/ProtocolBuffers.hs
@@ -5,7 +5,7 @@
 
 {-# LANGUAGE DeriveGeneric, DataKinds, MultiParamTypeClasses #-}
 {-# LANGUAGE FlexibleContexts, UndecidableInstances #-}
-{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE OverloadedStrings, MonoLocalBinds #-}
 
 {- | Protocol buffers serialization for the debug-me wire protocol.
  - 
@@ -319,6 +319,7 @@ instance Encode a => Encode (MessageP a)
 -- This is why UndecidableInstances is needed. The need
 -- for a Monoid instance is an implementation detail of
 -- Data.ProtocolBuffers.
+-- MonoLocalBinds is also used to avoid a ghc warning.
 instance (Monoid (Message a), Generic a, Decode a) => Decode (MessageP a)
 instance Encode a => Encode (ActivityP a)
 instance (Monoid (Message a), Generic a, Decode a) => Decode (ActivityP a)
diff --git a/Role/Developer.hs b/Role/Developer.hs
index d706a7a..abdad08 100644
--- a/Role/Developer.hs
+++ b/Role/Developer.hs
@@ -38,9 +38,10 @@ import qualified Data.Text as T
 import Data.List
 import Data.Maybe
 import Control.Monad
-import Data.Monoid
 import Data.Time.Clock.POSIX
 import Network.URI
+import Data.Monoid
+import Prelude
 
 run :: DeveloperOpts -> IO ()
 run = run' developer . debugUrl
diff --git a/Role/User.hs b/Role/User.hs
index 6ee1a42..6ec0302 100644
--- a/Role/User.hs
+++ b/Role/User.hs
@@ -30,11 +30,12 @@ import System.Exit
 import qualified Data.Text.IO as T
 import qualified Data.ByteString as B
 import Data.List.NonEmpty (NonEmpty(..), toList)
-import Data.Monoid
 import Data.Maybe
 import Data.Time.Clock.POSIX
 import System.IO
 import System.Environment
+import Data.Monoid
+import Prelude
 
 run :: UserOpts -> IO ExitCode
 run os = fromMaybe (ExitFailure 101) <$> connect
diff --git a/Session.hs b/Session.hs
index 9571ed1..7343e82 100644
--- a/Session.hs
+++ b/Session.hs
@@ -11,6 +11,7 @@ import qualified Data.ByteString as B
 import qualified Data.ByteString.Char8 as B8
 import System.Exit
 import Data.Monoid
+import Prelude
 
 startSession :: B.ByteString
 startSession = "** debug-me session started"
diff --git a/Types.hs b/Types.hs
index ce986c7..bbf296f 100644
--- a/Types.hs
+++ b/Types.hs
@@ -22,6 +22,7 @@ import JSON
 
 import qualified Data.Text as T
 import Data.Time.Clock.POSIX
+import qualified Data.Semigroup as Sem
 
 -- | Things that the developer sees.
 data Seen = Seen
@@ -194,9 +195,12 @@ newtype ElapsedTime = ElapsedTime Double
 mkElapsedTime :: POSIXTime -> POSIXTime -> ElapsedTime
 mkElapsedTime start end = ElapsedTime $ fromRational $ toRational (end - start)
 
+instance Sem.Semigroup ElapsedTime where
+	ElapsedTime a <> ElapsedTime b = ElapsedTime (a+b)
+
 instance Monoid ElapsedTime where
 	mempty = ElapsedTime 0
-	mappend (ElapsedTime a) (ElapsedTime b) = ElapsedTime (a+b)
+	mappend = (Sem.<>)
 
 instance DataSize ElapsedTime where
 	dataSize _ = 16 -- 128 bit Double
diff --git a/Val.hs b/Val.hs
index c395a95..f024b9d 100644
--- a/Val.hs
+++ b/Val.hs
@@ -16,10 +16,11 @@ import qualified Codec.Binary.Base64 as B64
 import qualified Data.Text as T
 import qualified Data.Text.Encoding as T
 import qualified Data.ByteString as B
+import qualified Data.Semigroup as Sem
 
 -- | Newtype of ByteString so we can have JSON instances without orphans.
 newtype Val = Val { val :: B.ByteString }
-	deriving (Show, Generic, Eq, Monoid)
+	deriving (Show, Generic, Eq, Sem.Semigroup, Monoid)
 
 instance DataSize Val where
 	dataSize (Val b) = fromIntegral (B.length b)
diff --git a/WebSockets.hs b/WebSockets.hs
index c2fcb95..7a53c8c 100644
--- a/WebSockets.hs
+++ b/WebSockets.hs
@@ -40,12 +40,13 @@ import qualified Data.Serialize
 import qualified Data.Text as T
 import qualified Data.ByteString.Lazy as L
 import Data.List
-import Data.Monoid
 import Data.Maybe
 import Text.Read
 import Control.Monad
 import Network.URI
 import System.IO
+import Data.Monoid
+import Prelude
 
 -- | Framing protocol used over a websocket connection.
 --
diff --git a/debug-me.cabal b/debug-me.cabal
index a601e34..9fa28b9 100644
--- a/debug-me.cabal
+++ b/debug-me.cabal
@@ -45,6 +45,9 @@ Extra-Source-Files:
   debug-me.default
   developer-keyring.gpg
 
+custom-setup
+  Setup-Depends: base (>= 4.9 && < 5.0), Cabal, filepath
+
 Executable debug-me
   Main-Is: debug-me.hs
   GHC-Options: -threaded -Wall -fno-warn-tabs -O2
@@ -60,11 +63,11 @@ Executable debug-me
     , stm-chans (>= 3.0)
     , posix-pty (>= 0.2.1)
     , terminal-size (>= 0.3)
-    , aeson (>= 0.11 && < 1.3)
+    , aeson (>= 0.11 && < 1.4)
     , sandi (>= 0.4)
     , text (>= 1.2.2)
     , optparse-applicative (>= 0.12)
-    , graphviz (== 2999.18.*)
+    , graphviz (>= 2999.18.0 && < 2999.21)
     , time (>= 1.6)
     , filepath (>= 1.4)
     , directory (>= 1.2)
diff --git a/doc/bugs/fails_to_build_against_current_LTS_Haskell.mdwn b/doc/bugs/fails_to_build_against_current_LTS_Haskell.mdwn
index 52b9faf..2d1c0aa 100644
--- a/doc/bugs/fails_to_build_against_current_LTS_Haskell.mdwn
+++ b/doc/bugs/fails_to_build_against_current_LTS_Haskell.mdwn
@@ -13,3 +13,5 @@ debug-me fails to build against LTS 8.23:
     make[2]: *** [debug-me] Error 1
 
 --spwhitton
+
+> [[fixed|done]] --[[Joey]]
diff --git a/stack.yaml b/stack.yaml
index abe5576..ca6d0ad 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,9 +1,8 @@
 packages:
 - '.'
-resolver: lts-11.17
+resolver: lts-12.10
 extra-deps:
-- graphviz-2999.18.1.2
+- graphviz-2999.20.0.2
 - posix-pty-0.2.1.1
 - sandi-0.4.2
-- fgl-5.5.4.0
 explicit-setup-deps: