htools: allow unittest to be replayed

This just adds glue to allow replaying of tests using a given RNG state
and test size (both are needed for exact replayability).

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>

htools/Ganeti/HTools/CLI.hs

@@ -67,6 +67,7 @@ module Ganeti.HTools.CLI
     , oPrintNodes
     , oQuiet
     , oRapiMaster
+    , oReplay
     , oSaveCluster
     , oShowHelp
     , oShowVer
@@ -126,6 +127,7 @@ data Options = Options
     , optShowNodes   :: Maybe [String] -- ^ Whether to show node status
     , optShowVer     :: Bool           -- ^ Just show the program version
     , optTieredSpec  :: Maybe RSpec    -- ^ Requested specs for tiered mode
+    , optReplay      :: Maybe String   -- ^ Unittests: RNG state
     , optVerbose     :: Int            -- ^ Verbosity level
     } deriving Show
 
@@ -164,6 +166,7 @@ defaultOptions  = Options
  , optShowNodes   = Nothing
  , optShowVer     = False
  , optTieredSpec  = Nothing
+ , optReplay      = Nothing
  , optVerbose     = 1
  }
 
@@ -381,6 +384,11 @@ oTieredSpec = Option "" ["tiered-alloc"]
               "TSPEC")
              "enable tiered specs allocation, given as 'disk,ram,cpu'"
 
+oReplay :: OptType
+oReplay = Option "" ["replay"]
+          (ReqArg (\ stat opts -> Ok opts { optReplay = Just stat } ) "STATE")
+          "Pre-seed the random number generator with STATE"
+
 oVerbose :: OptType
 oVerbose = Option "v" ["verbose"]
            (NoArg (\ opts -> Ok opts { optVerbose = optVerbose opts + 1 }))

htools/test.hs

@@ -27,12 +27,24 @@ module Main(main) where
 
 import Data.IORef
 import Test.QuickCheck
+import System.Console.GetOpt
 import System.IO
 import System.Exit
 import System (getArgs)
 import Text.Printf
 
 import Ganeti.HTools.QC
+import Ganeti.HTools.CLI
+import Ganeti.HTools.Utils (sepSplit)
+
+-- | Options list and functions
+options :: [OptType]
+options =
+    [ oReplay
+    , oVerbose
+    , oShowVer
+    , oShowHelp
+    ]
 
 fast :: Args
 fast = stdArgs
@@ -101,16 +113,32 @@ allTests =
   , ("Cluster", slow, testCluster)
   ]
 
+transformTestOpts :: Args -> Options -> IO Args
+transformTestOpts args opts = do
+  r <- case optReplay opts of
+         Nothing -> return Nothing
+         Just str -> do
+           let vs = sepSplit ',' str
+           (case vs of
+              [rng, size] -> return $ Just (read rng, read size)
+              _ -> fail "Invalid state given")
+  return args { chatty = optVerbose opts > 1,
+                replay = r
+              }
+
 main :: IO ()
 main = do
   errs <- newIORef 0
   let wrap = map (wrapTest errs)
-  args <- getArgs
+  cmd_args <- System.getArgs
+  (opts, args) <- parseOpts cmd_args "test" options
   let tests = if null args
               then allTests
               else filter (\(name, _, _) -> name `elem` args) allTests
       max_count = maximum $ map (\(_, _, t) -> length t) tests
-  mapM_ (\(name, opts, tl) -> runTests name opts (wrap tl) max_count) tests
+  mapM_ (\(name, targs, tl) ->
+             transformTestOpts targs opts >>= \newargs ->
+             runTests name newargs (wrap tl) max_count) tests
   terr <- readIORef errs
   (if terr > 0
    then do