Add CLI command to generate sample config

lib/Echidna/Utility.hs

@@ -4,6 +4,7 @@ import Control.Monad (unless)
 import Control.Monad.Catch (bracket)
 import Data.Time (diffUTCTime, getCurrentTime, zonedTimeToLocalTime, LocalTime, getZonedTime)
 import Data.Time.Format (defaultTimeLocale, formatTime)
+import Language.Haskell.TH
 import System.Directory (getDirectoryContents, getCurrentDirectory, setCurrentDirectory)
 import System.IO (hFlush, stdout)
 
@@ -38,3 +39,6 @@ withCurrentDirectory dir action =
   bracket getCurrentDirectory setCurrentDirectory $ \_ -> do
     setCurrentDirectory dir
     action
+
+includeFile :: FilePath -> Q Exp
+includeFile fp = LitE . StringL <$> runIO (readFile fp)

package.yaml

@@ -25,6 +25,18 @@ dependencies:
   - MonadRandom
   - mtl
   - text
+  - transformers
+  - time
+  - unliftio
+  - utf8-string
+  - vector
+  - with-utf8
+  - word-wrap
+  - yaml
+  - http-conduit
+  - html-conduit
+  - xml-conduit
+  - template-haskell
 
 language: GHC2021
 

src/Main.hs

@@ -1,4 +1,5 @@
 {-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE TemplateHaskell #-}
 
 module Main where
 
@@ -22,7 +23,7 @@ import Data.Word (Word8, Word16, Word64)
 import Main.Utf8 (withUtf8)
 import Options.Applicative
 import Paths_echidna (version)
-import System.Directory (createDirectoryIfMissing)
+import System.Directory (createDirectoryIfMissing, doesFileExist)
 import System.Environment (lookupEnv)
 import System.Exit (exitWith, exitSuccess, ExitCode(..))
 import System.FilePath ((</>), (<.>))
@@ -47,11 +48,26 @@ import Echidna.Types.Solidity
 import Echidna.Types.Test (TestMode, EchidnaTest(..))
 import Echidna.UI
 import Echidna.UI.Report (ppFailWithTraces, ppTestName)
-import Echidna.Utility (measureIO)
+import Echidna.Utility (includeFile, measureIO)
 
 main :: IO ()
 main = withUtf8 $ withCP65001 $ do
-  opts@Options{..} <- execParser optsParser
+  cli <- execParser cliParser
+  case cli of
+    InitCommand -> do
+      let config = "echidna.yaml"
+      configExists <- doesFileExist config
+      if configExists then do
+        putStrLn $ "Config file " <> config <> " already exists."
+        exitWith (ExitFailure 1)
+      else do
+        writeFile config $(includeFile "tests/solidity/basic/default.yaml")
+        putStrLn $ "Sample config file written to " <> config
+    FuzzCommand fuzzOpts ->
+      fuzz fuzzOpts
+
+fuzz :: FuzzOptions -> IO ()
+fuzz opts@FuzzOptions{..} = do
   EConfigWithUsage loadedCfg ks _ <-
     maybe (pure (EConfigWithUsage defaultConfig mempty mempty)) parseConfig cliConfigFilepath
   cfg <- overrideConfig loadedCfg opts
@@ -118,7 +134,11 @@ main = withUtf8 $ withCP65001 $ do
 
   if isSuccessful tests then exitSuccess else exitWith (ExitFailure 1)
 
-data Options = Options
+data CLI
+  = InitCommand
+  | FuzzCommand FuzzOptions
+
+data FuzzOptions = FuzzOptions
   { cliFilePath         :: NE.NonEmpty FilePath
   , cliWorkers          :: Maybe Word8
   , cliServerPort       :: Maybe Word16
@@ -147,19 +167,25 @@ data Options = Options
   , cliSymExecNSolvers  :: Maybe Int
   }
 
-optsParser :: ParserInfo Options
-optsParser = info (helper <*> versionOption <*> options) $ fullDesc
+cliParser :: ParserInfo CLI
+cliParser = info (helper <*> versionOption <*> commands) $ fullDesc
   <> progDesc "EVM property-based testing framework"
   <> header "Echidna"
+  where
+  commands = subparser $
+    command "init" (info (pure InitCommand)
+            (progDesc "Write a sample config file to echidna.yaml"))
+    <> command "fuzz" (info (FuzzCommand <$> fuzzOptions)
+               (progDesc "Run fuzzing"))
 
 bool :: ReadM Bool
 bool = maybeReader (f . map toLower) where
   f "true" = Just True
   f "false" = Just False
   f _ = Nothing
 
-options :: Parser Options
-options = Options . NE.fromList
+fuzzOptions :: Parser FuzzOptions
+fuzzOptions = FuzzOptions . NE.fromList
   <$> some (argument str (metavar "FILES"
     <> help "Solidity files to analyze"))
   <*> optional (option auto $ long "workers"
@@ -240,8 +266,8 @@ versionOption = infoOption
                   ("Echidna " ++ showVersion version)
                   (long "version" <> help "Show version")
 
-overrideConfig :: EConfig -> Options -> IO EConfig
-overrideConfig config Options{..} = do
+overrideConfig :: EConfig -> FuzzOptions -> IO EConfig
+overrideConfig config FuzzOptions{..} = do
   envRpcUrl <- Onchain.rpcUrlEnv
   envRpcBlock <- Onchain.rpcBlockEnv
   envEtherscanApiKey <- Onchain.etherscanApiKey
@@ -295,4 +321,4 @@ overrideConfig config Options{..} = do
 printProjectName :: Maybe Text -> IO ()
 printProjectName (Just name) = putStrLn $
     "This is Echidna " <> showVersion version <> " running on project `" <> T.unpack name <> "`"
-printProjectName Nothing = pure ()
+printProjectName Nothing = pure ()