Removed dependency on MissingH, instead depends on split and hashable.

MissingH is a heavy dependency, which pulls in parsec and a bunch of stuff.
So eliminating it makes propellor easier to install and less likely to
fail to build.

changesFileContent now uses hashable's hash. This may not be stable across
upgrades, I'm not sure -- but it's surely ok here, as the hash is not
stored.

socketFile also uses hash. I *think* this is ok, even if it's not stable.
If it's not stable, an upgrade might make propellor hash a hostname to a
different number, but with 9 digets of number in use, the chances of a
collision are small. In any case, I've opned a bug report asking for the
stability to be documented, and I think it's intended to be stable, only
the documentation is bad.

NB: I have not checked that the arch linux and freebsd packages for the new
deps, that Propellor.Bootstrap lists, are the right names or even exist.

Since propellor depends on hashable, it could be changed to use
unordered-containers, rather than containers, which would be faster and
perhaps less deps too.

This commit was sponsored by Alexander Thompson on Patreon.

14 files changed, 39 insertions, 36 deletions

diff --git a/src/Propellor/Bootstrap.hs b/src/Propellor/Bootstrap.hs
index 29c55213..a3b7f315 100644
--- a/src/Propellor/Bootstrap.hs
+++ b/src/Propellor/Bootstrap.hs
@@ -83,7 +83,7 @@ depsCommand msys = "( " ++ intercalate " ; " (concat [osinstall, cabalinstall])
 		, "ghc"
 		, "cabal-install"
 		, "libghc-async-dev"
-		, "libghc-missingh-dev"
+		, "libghc-split-dev"
 		, "libghc-hslogger-dev"
 		, "libghc-unix-compat-dev"
 		, "libghc-ansi-terminal-dev"
@@ -94,13 +94,14 @@ depsCommand msys = "( " ++ intercalate " ; " (concat [osinstall, cabalinstall])
 		, "libghc-exceptions-dev"
 		, "libghc-stm-dev"
 		, "libghc-text-dev"
+		, "libghc-hashable-dev"
 		]
 	fbsddeps =
 		[ "gnupg"
 		, "ghc"
 		, "hs-cabal-install"
 		, "hs-async"
-		, "hs-MissingH"
+		, "hs-split"
 		, "hs-hslogger"
 		, "hs-unix-compat"
 		, "hs-ansi-terminal"
@@ -111,13 +112,14 @@ depsCommand msys = "( " ++ intercalate " ; " (concat [osinstall, cabalinstall])
 		, "hs-exceptions"
 		, "hs-stm"
 		, "hs-text"
+		, "hs-hashable"
 		]
 	archlinuxdeps =
 		[ "gnupg"
 		, "ghc"
 		, "cabal-install"
 		, "haskell-async"
-		, "haskell-missingh"
+		, "haskell-split"
 		, "haskell-hslogger"
 		, "haskell-unix-compat"
 		, "haskell-ansi-terminal"
@@ -129,6 +131,7 @@ depsCommand msys = "( " ++ intercalate " ; " (concat [osinstall, cabalinstall])
 		, "haskell-exceptions"
 		, "haskell-stm"
 		, "haskell-text"
+		, "hashell-hashable"
 		]
 
 installGitCommand :: Maybe System -> ShellCommand
diff --git a/src/Propellor/Gpg.hs b/src/Propellor/Gpg.hs
index 6ac153cc..43c4eddf 100644
--- a/src/Propellor/Gpg.hs
+++ b/src/Propellor/Gpg.hs
@@ -2,7 +2,6 @@ module Propellor.Gpg where
 
 import System.IO
 import Data.Maybe
-import Data.List.Utils
 import Control.Monad
 import Control.Applicative
 import Prelude
@@ -18,6 +17,7 @@ import Utility.Misc
 import Utility.Tmp
 import Utility.Env
 import Utility.Directory
+import Utility.Split
 
 type KeyId = String
 
diff --git a/src/Propellor/Property.hs b/src/Propellor/Property.hs
index 94c82c9f..8b2a4e3d 100644
--- a/src/Propellor/Property.hs
+++ b/src/Propellor/Property.hs
@@ -50,8 +50,8 @@ import Data.Monoid
 import Control.Monad.IfElse
 import "mtl" Control.Monad.RWS.Strict
 import System.Posix.Files
-import qualified Data.Hash.MD5 as MD5
 import Data.List
+import Data.Hashable
 import Control.Applicative
 import Prelude
 
@@ -64,8 +64,8 @@ import Propellor.Info
 import Propellor.EnsureProperty
 import Utility.Exception
 import Utility.Monad
-import Utility.Misc
 import Utility.Directory
+import Utility.Misc
 
 -- | Makes a perhaps non-idempotent Property be idempotent by using a flag
 -- file to indicate whether it has run before.
@@ -228,12 +228,12 @@ changesFile p f = checkResult getstat comparestat p
 -- Changes to mtime etc that do not change file content are treated as
 -- NoChange.
 changesFileContent :: Checkable p i => p i -> FilePath -> Property i
-changesFileContent p f = checkResult getmd5 comparemd5 p
+changesFileContent p f = checkResult gethash comparehash p
   where
-	getmd5 = catchMaybeIO $ MD5.md5 . MD5.Str <$> readFileStrict f
-	comparemd5 oldmd5 = do
-		newmd5 <- getmd5
-		return $ if oldmd5 == newmd5 then NoChange else MadeChange
+	gethash = catchMaybeIO $ hash <$> readFileStrict f
+	comparehash oldhash = do
+		newhash <- gethash
+		return $ if oldhash == newhash then NoChange else MadeChange
 
 -- | Determines if the first file is newer than the second file.
 --
diff --git a/src/Propellor/Property/Apt/PPA.hs b/src/Propellor/Property/Apt/PPA.hs
index 346125ff..a8f7db15 100644
--- a/src/Propellor/Property/Apt/PPA.hs
+++ b/src/Propellor/Property/Apt/PPA.hs
@@ -6,10 +6,11 @@ module Propellor.Property.Apt.PPA where
 import Data.List
 import Control.Applicative
 import Prelude
-import Data.String.Utils
 import Data.String (IsString(..))
+
 import Propellor.Base
 import qualified Propellor.Property.Apt as Apt
+import Utility.Split
 
 -- | Ensure software-properties-common is installed.
 installed :: Property DebianLike
diff --git a/src/Propellor/Property/Chroot.hs b/src/Propellor/Property/Chroot.hs
index 7738d97e..01cd4d3e 100644
--- a/src/Propellor/Property/Chroot.hs
+++ b/src/Propellor/Property/Chroot.hs
@@ -32,9 +32,9 @@ import qualified Propellor.Property.File as File
 import qualified Propellor.Shim as Shim
 import Propellor.Property.Mount
 import Utility.FileMode
+import Utility.Split
 
 import qualified Data.Map as M
-import Data.List.Utils
 import System.Posix.Directory
 import System.Console.Concurrent
 
diff --git a/src/Propellor/Property/Docker.hs b/src/Propellor/Property/Docker.hs
index 1080418b..d53bab71 100644
--- a/src/Propellor/Property/Docker.hs
+++ b/src/Propellor/Property/Docker.hs
@@ -59,13 +59,13 @@ import qualified Propellor.Property.Pacman as Pacman
 import qualified Propellor.Shim as Shim
 import Utility.Path
 import Utility.ThreadScheduler
+import Utility.Split
 
 import Control.Concurrent.Async hiding (link)
 import System.Posix.Directory
 import System.Posix.Process
 import Prelude hiding (init)
 import Data.List hiding (init)
-import Data.List.Utils
 import qualified Data.Map as M
 import System.Console.Concurrent
 
diff --git a/src/Propellor/Property/Hostname.hs b/src/Propellor/Property/Hostname.hs
index e1342d91..1eb9d690 100644
--- a/src/Propellor/Property/Hostname.hs
+++ b/src/Propellor/Property/Hostname.hs
@@ -3,9 +3,9 @@ module Propellor.Property.Hostname where
 import Propellor.Base
 import qualified Propellor.Property.File as File
 import Propellor.Property.Chroot (inChroot)
+import Utility.Split
 
 import Data.List
-import Data.List.Utils
 
 -- | Ensures that the hostname is set using best practices, to whatever
 -- name the `Host` has.
diff --git a/src/Propellor/Property/Sbuild.hs b/src/Propellor/Property/Sbuild.hs
index 00109381..460d0b16 100644
--- a/src/Propellor/Property/Sbuild.hs
+++ b/src/Propellor/Property/Sbuild.hs
@@ -98,10 +98,10 @@ import qualified Propellor.Property.File as File
 import qualified Propellor.Property.Schroot as Schroot
 import qualified Propellor.Property.Reboot as Reboot
 import qualified Propellor.Property.User as User
-
 import Utility.FileMode
+import Utility.Split
+
 import Data.List
-import Data.List.Utils
 
 type Suite = String
 
diff --git a/src/Propellor/Property/SiteSpecific/JoeySites.hs b/src/Propellor/Property/SiteSpecific/JoeySites.hs
index 063a2eda..9b4a3378 100644
--- a/src/Propellor/Property/SiteSpecific/JoeySites.hs
+++ b/src/Propellor/Property/SiteSpecific/JoeySites.hs
@@ -22,10 +22,10 @@ import qualified Propellor.Property.Systemd as Systemd
 import qualified Propellor.Property.Fail2Ban as Fail2Ban
 import qualified Propellor.Property.LetsEncrypt as LetsEncrypt
 import Utility.FileMode
+import Utility.Split
 
 import Data.List
 import System.Posix.Files
-import Data.String.Utils
 
 scrollBox :: Property (HasInfo + DebianLike)
 scrollBox = propertyList "scroll server" $ props
diff --git a/src/Propellor/Property/Systemd.hs b/src/Propellor/Property/Systemd.hs
index 7c40bd16..d1a94aa8 100644
--- a/src/Propellor/Property/Systemd.hs
+++ b/src/Propellor/Property/Systemd.hs
@@ -55,9 +55,9 @@ import qualified Propellor.Property.Apt as Apt
 import qualified Propellor.Property.File as File
 import Propellor.Property.Systemd.Core
 import Utility.FileMode
+import Utility.Split
 
 import Data.List
-import Data.List.Utils
 import qualified Data.Map as M
 
 type ServiceName = String
diff --git a/src/Propellor/Property/ZFS/Process.hs b/src/Propellor/Property/ZFS/Process.hs
index 372bac6d..42b23df2 100644
--- a/src/Propellor/Property/ZFS/Process.hs
+++ b/src/Propellor/Property/ZFS/Process.hs
@@ -5,7 +5,8 @@
 module Propellor.Property.ZFS.Process where
 
 import Propellor.Base
-import Data.String.Utils (split)
+import Utility.Split
+
 import Data.List
 
 -- | Gets the properties of a ZFS volume.
diff --git a/src/Propellor/Ssh.hs b/src/Propellor/Ssh.hs
index a7a9452e..a8f50ed0 100644
--- a/src/Propellor/Ssh.hs
+++ b/src/Propellor/Ssh.hs
@@ -6,7 +6,7 @@ import Utility.FileSystemEncoding
 
 import System.PosixCompat
 import Data.Time.Clock.POSIX
-import qualified Data.Hash.MD5 as MD5
+import Data.Hashable
 
 -- Parameters can be passed to both ssh and scp, to enable a ssh connection
 -- caching socket.
@@ -50,24 +50,22 @@ sshCachingParams hn = do
 -- 100 bytes. Try to never construct a filename longer than that.
 --
 -- When space allows, include the full hostname in the socket filename.
--- Otherwise, include at least a partial md5sum of it,
--- to avoid using the same socket file for multiple hosts.
+-- Otherwise, a checksum of the hostname is included in the name, to
+-- avoid using the same socket file for multiple hosts.
 socketFile :: FilePath -> HostName -> FilePath
 socketFile home hn = selectSocketFile
-	[  sshdir </> hn ++ ".sock"
+	[ sshdir </> hn ++ ".sock"
 	, sshdir </> hn
-	, sshdir </> take 10 hn ++ "-" ++ md5
-	, sshdir </> md5
-	, home </> ".propellor-" ++ md5
+	, sshdir </> take 10 hn ++ "-" ++ checksum
+	, sshdir </> checksum
 	]
-	(".propellor-" ++ md5)
+	(home </> ".propellor-" ++ checksum)
   where
 	sshdir = home </> ".ssh" </> "propellor"
-	md5 = take 9 $ MD5.md5s $ MD5.Str hn
+	checksum = take 9 $ show $ abs $ hash hn
 
 selectSocketFile :: [FilePath] -> FilePath -> FilePath
 selectSocketFile [] d = d
-selectSocketFile [f] _ = f
 selectSocketFile (f:fs) d
 	| valid_unix_socket_path f = f
 	| otherwise = selectSocketFile fs d
diff --git a/src/Propellor/Types/Dns.hs b/src/Propellor/Types/Dns.hs
index 8d62e63b..87756d81 100644
--- a/src/Propellor/Types/Dns.hs
+++ b/src/Propellor/Types/Dns.hs
@@ -6,12 +6,12 @@ import Propellor.Types.OS (HostName)
 import Propellor.Types.Empty
 import Propellor.Types.Info
 import Propellor.Types.ConfigurableValue
+import Utility.Split
 
 import Data.Word
 import qualified Data.Map as M
 import qualified Data.Set as S
 import Data.List
-import Data.String.Utils (split, replace)
 import Data.Monoid
 import Prelude
 
@@ -102,14 +102,14 @@ data Record
 type ReverseIP = String
 
 reverseIP :: IPAddr -> ReverseIP
-reverseIP (IPv4 addr) = intercalate "." (reverse $ split "." addr) ++ ".in-addr.arpa"
+reverseIP (IPv4 addr) = intercalate "." (reverse $ splitc '.' addr) ++ ".in-addr.arpa"
 reverseIP addr@(IPv6 _) = reverse (intersperse '.' $ replace ":" "" $ val $ canonicalIP addr) ++ ".ip6.arpa"
 
 -- | Converts an IP address (particularly IPv6) to canonical, fully
 -- expanded form.
 canonicalIP :: IPAddr -> IPAddr
 canonicalIP (IPv4 addr) = IPv4 addr
-canonicalIP (IPv6 addr) = IPv6 $ intercalate ":" $ map canonicalGroup $ split ":" $ replaceImplicitGroups addr
+canonicalIP (IPv6 addr) = IPv6 $ intercalate ":" $ map canonicalGroup $ splitc ':' $ replaceImplicitGroups addr
   where
 	canonicalGroup g
 		| l <= 4    = replicate (4 - l) '0' ++ g
@@ -117,7 +117,7 @@ canonicalIP (IPv6 addr) = IPv6 $ intercalate ":" $ map canonicalGroup $ split ":
 	  where
 		l = length g
 	emptyGroups n = iterate (++ ":") "" !! n
-	numberOfImplicitGroups a = 8 - length (split ":" $ replace "::" "" a)
+	numberOfImplicitGroups a = 8 - length (splitc ':' $ replace "::" "" a)
 	replaceImplicitGroups a = concat $ aux $ split "::" a
 	  where
 		aux [] = []
diff --git a/src/Propellor/Types/ZFS.hs b/src/Propellor/Types/ZFS.hs
index 22b848fa..c68f6ba5 100644
--- a/src/Propellor/Types/ZFS.hs
+++ b/src/Propellor/Types/ZFS.hs
@@ -7,10 +7,10 @@
 module Propellor.Types.ZFS where
 
 import Propellor.Types.ConfigurableValue
+import Utility.Split
 
 import Data.String
 import qualified Data.Set as Set
-import qualified Data.String.Utils as SU
 import Data.List
 
 -- | A single ZFS filesystem.
@@ -46,7 +46,7 @@ instance Show ZDataset where
 	show = val
 
 instance IsString ZDataset where
-	fromString s = ZDataset $ SU.split "/" s
+	fromString s = ZDataset $ splitc '/' s
 
 instance IsString ZPool where
 	fromString p = ZPool p