sim visit as first-class command

Allows using it in a sim file.

Annex/Sim.hs

@@ -35,6 +35,7 @@ import Logs.MaxSize
 import Logs.Difference
 import Logs.UUID
 import Logs.Location
+import Utility.Env
 import qualified Annex
 import qualified Remote
 import qualified Git.Construct
@@ -222,6 +223,7 @@ data SimCommand
 	| CommandGroupWanted Group PreferredContentExpression
 	| CommandMaxSize RepoName MaxSize
 	| CommandRebalance Bool
+	| CommandVisit RepoName [String]
 	| CommandComment String
 	| CommandBlank
 	deriving (Show, Read)
@@ -278,6 +280,32 @@ applySimCommand (CommandNotPresent repo file) st _ = checkKnownRepo repo st $ \u
 	present = Left $ "Expected " ++ fromRawFilePath file 
 		++ " not to be present in " 
 		++ fromRepoName repo ++ ", but it is present."
+applySimCommand c@(CommandVisit repo cmdparams) st _ =
+	checkKnownRepo repo st $ \u -> Right $ Left $ do
+		st' <- liftIO $ updateSimRepos st
+		let dir = simRepoDirectory st' u
+		unlessM (liftIO $ doesDirectoryExist dir) $
+			giveup "Simulated repository unavailable."
+		(cmd, params) <- case cmdparams of
+			(cmd:params) -> return (cmd, params)
+			[] -> do
+				showLongNote "Starting a shell in the simulated repository."
+				shellcmd <- liftIO $ fromMaybe "sh" <$> getEnv "SHELL"
+				return (shellcmd, [])
+		exitcode <- liftIO $
+			safeSystem' cmd (map Param params)
+				(\p -> p { cwd = Just dir })
+		when (null cmdparams) $
+			showLongNote "Finished visit to simulated repository."
+		if null cmdparams
+			then return st'
+			else if exitcode == ExitSuccess
+				then return $ addHistory st' c
+				else do
+					showLongNote $ UnquotedString $ 
+						"Command " ++ unwords cmdparams ++
+							" exited nonzero."
+					liftIO $ exitWith exitcode
 applySimCommand cmd st repobyname = 
 	let st' = flip addHistory cmd $ st
 		{ simVectorClock = 
@@ -455,6 +483,7 @@ applySimCommand' (CommandRebalance b) st _ =
 		}
 applySimCommand' (CommandComment _) st _ = Right $ Right st
 applySimCommand' CommandBlank st _ = Right $ Right st
+applySimCommand' (CommandVisit _ _) _ _ = error "applySimCommand' CommandVisit"
 applySimCommand' (CommandPresent _ _) _ _ = error "applySimCommand' CommandPresent"
 applySimCommand' (CommandNotPresent _ _) _ _ = error "applySimCommand' CommandNotPresent"
 
@@ -716,7 +745,8 @@ checkKnownRepo :: RepoName -> SimState SimRepo -> (UUID -> Either String a) -> E
 checkKnownRepo reponame st a = case M.lookup reponame (simRepos st) of
 	Just u -> a u
 	Nothing -> Left $ "No repository in the simulation is named \""
-		++ fromRepoName reponame ++ "\"."
+		++ fromRepoName reponame ++ "\". Choose from: "
+		++ unwords (map fromRepoName $ M.keys (simRepos st))
 
 checkKnownRemote :: RemoteName -> RepoName -> UUID -> SimState SimRepo -> (UUID -> Either String a) -> Either String a
 checkKnownRemote remotename reponame u st a =

Annex/Sim/File.hs

@@ -80,6 +80,8 @@ generateSimFile = unlines . map unwords . go
 		["maxsize", repo, showsize (fromMaxSize maxsize)] : go rest
 	go (CommandRebalance b : rest) =
 		["rebalance", if b then "on" else "off"] : go rest
+	go (CommandVisit (RepoName repo) cmdparams : rest) =
+		(["visit", repo] ++ cmdparams) : go rest
 	go (CommandComment s : rest) = 
 		[s] : go rest
 	go (CommandBlank : rest) = 
@@ -184,6 +186,8 @@ parseSimCommand ("maxsize":repo:size:[]) =
 parseSimCommand ("rebalance":onoff:[]) = case isTrueFalse onoff of
 	Just b -> Right $ CommandRebalance b
 	Nothing -> Left $ "Unable to parse rebalance value \"" ++ onoff ++ "\""
+parseSimCommand ("visit":repo:cmdparams) =
+	Right $ CommandVisit (RepoName repo) cmdparams
 parseSimCommand ws = parseError ws
 
 parseSimAction :: [String] -> Either String SimAction

Command/Sim.hs

@@ -13,10 +13,8 @@ import Command
 import Annex.Sim
 import Annex.Sim.File
 import Annex.Perms
-import Utility.Env
 
 import System.Random
-import qualified Data.Map as M
 
 cmd :: Command
 cmd = command "sim" SectionTesting
@@ -31,27 +29,6 @@ seek ("end":[]) = do
 	whenM (liftIO $ doesDirectoryExist simdir) $ do
 		liftIO $ removeDirectoryRecursive simdir
 	showLongNote $ UnquotedString "Sim ended."
-seek ("visit":reponame:[]) = do
-	simdir <- fromRepo gitAnnexSimDir
-	liftIO (restoreSim simdir) >>= \case
-		Left err -> giveup err
-		Right st -> case M.lookup (RepoName reponame) (simRepos st) of
-			Just u -> do
-				let dir = simRepoDirectory st u
-				unlessM (liftIO $ doesDirectoryExist dir) $
-					giveup "Simulated repository unavailable."
-				showLongNote "Starting a shell in the simulated repository."
-				shellcmd <- liftIO $ fromMaybe "sh" <$> getEnv "SHELL"
-				exitcode <- liftIO $
-					safeSystem' shellcmd []
-						(\p -> p { cwd = Just dir })
-				showLongNote "Finished visit to simulated repository."
-				liftIO $ exitWith exitcode
-			Nothing -> giveup $ unwords
-				[ "There is no simulated repository with that name."
-				, "Choose from:" 
-				, unwords $ map fromRepoName $ M.keys (simRepos st)
-				]
 seek ("show":[]) = do
 	simdir <- fromRepo gitAnnexSimDir
 	liftIO (restoreSim simdir) >>= \case

doc/git-annex-sim.mdwn

@@ -8,8 +8,6 @@ git annex sim start [my.sim]
 
 git annex sim command
 
-git annex sim visit repo
-
 git annex sim show
 
 git annex sim end
@@ -32,14 +30,6 @@ simulation, and the results of the simulation. Use "git-annex sim show"
 to display the log. This allows re-running the same simulation later,
 as well as analyzing the results of the simulation.
 
-While a simulation is running, the command "git annex sim visit repo", where
-"repo" is the name of one of the repositories in the simulation, will spawn
-a subshell in a git repository whose git-annex branch contains the state of
-that simulated repository. This allows running any git-annex command, such
-as `git-annex whereis` to examine the state of the simulation.
-You should avoid making any changes to git-annex state.
-Exit the subshell to end the visit.
-
 Use "git annex sim end" to finish the simulation, and clean up.
 
 # THE SIM FILE
@@ -109,6 +99,19 @@ as passed to "git annex sim" while a simulation is running.
   The repository to use can be specified by remote name, uuid, etc.
   Example: "use myrepo here"
 
+* `visit repo [command]`
+
+  Runs the specified shell command inside the simulated repository,
+  and waits for it to exit.
+
+  When no shell command is specified, it runs an interactive shell.
+
+  The command is run in a git repository whosegit-annex branch contains
+  the state of that simulated repository. This allows running any 
+  git-annex commands, such as `git-annex whereis` to examine the
+  state of the simulation. You should avoid making any changes to
+  git-annex state.
+
 * `connect repo [<-|->|<->] repo [...]`
 
   Add a connection between two or more repositories. The arrow indicates