ABI array fixes

Now correctly parses ABI array types,
and shows ABI array values in traces.

default.nix

@@ -1,12 +1,12 @@
 { mkDerivation, abstract-par, aeson, ansi-wl-pprint, async, base
 , base16-bytestring, base64-bytestring, binary, brick, bytestring
 , cereal, containers, cryptonite, data-dword, deepseq, directory
-, fgl, filepath, ghci-pretty, here, HUnit, lens, lens-aeson, memory
-, monad-par, mtl, multiset, operational, optparse-generic, process
-, QuickCheck, quickcheck-text, readline, restless-git, rosezipper
-, scientific, stdenv, tasty, tasty-hunit, tasty-quickcheck
-, temporary, text, text-format, time, transformers, tree-view
-, unordered-containers, vector, vty, wreq
+, fgl, filepath, ghci-pretty, here, HUnit, lens, lens-aeson
+, megaparsec, memory, monad-par, mtl, multiset, operational
+, optparse-generic, process, QuickCheck, quickcheck-text, readline
+, restless-git, rosezipper, scientific, stdenv, tasty, tasty-hunit
+, tasty-quickcheck, temporary, text, text-format, time
+, transformers, tree-view, unordered-containers, vector, vty, wreq
 }:
 mkDerivation {
   pname = "hevm";
@@ -19,10 +19,11 @@ mkDerivation {
     abstract-par aeson ansi-wl-pprint base base16-bytestring
     base64-bytestring binary brick bytestring cereal containers
     cryptonite data-dword deepseq directory fgl filepath ghci-pretty
-    lens lens-aeson memory monad-par mtl multiset operational
-    optparse-generic process QuickCheck quickcheck-text readline
-    restless-git rosezipper scientific temporary text text-format time
-    transformers tree-view unordered-containers vector vty wreq
+    lens lens-aeson megaparsec memory monad-par mtl multiset
+    operational optparse-generic process QuickCheck quickcheck-text
+    readline restless-git rosezipper scientific temporary text
+    text-format time transformers tree-view unordered-containers vector
+    vty wreq
   ];
   executableHaskellDepends = [
     aeson ansi-wl-pprint async base base16-bytestring base64-bytestring

hevm.cabal

@@ -79,6 +79,7 @@ library
     transformers                      == 0.5.*,
     lens                              >= 4.15.1 && < 4.16,
     lens-aeson                        >= 1.0.1 && < 1.1,
+    megaparsec                        == 6.*,
     memory                            >= 0.14.5 && < 0.15,
     monad-par                         >= 0.3 && < 0.4,
     mtl                               >= 2.2.1 && < 2.3,

shell.nix

@@ -25,6 +25,7 @@ let
       restless-git =
         with pkgs.haskell.lib;
           dontCheck (self.callPackage restless-git {});
+      megaparsec = super.megaparsec_6_2_0;
     });
   };
 

src/EVM/ABI.hs

@@ -48,14 +48,14 @@ module EVM.ABI
 import EVM.Keccak (abiKeccak)
 import EVM.Types ()
 
-import Control.Monad      (replicateM, replicateM_, forM_)
+import Control.Monad      (replicateM, replicateM_, forM_, void)
 import Data.Binary.Get    (Get, label, getWord8, getWord32be, skip)
 import Data.Binary.Put    (Put, runPut, putWord8, putWord32be)
 import Data.Bits          (shiftL, shiftR, (.&.))
 import Data.ByteString    (ByteString)
 import Data.DoubleWord    (Word256, Int256, Word160, signedWord)
 import Data.Monoid        ((<>))
-import Data.Text          (Text, pack, unpack, isPrefixOf)
+import Data.Text          (Text, pack)
 import Data.Text.Encoding (encodeUtf8)
 import Data.Vector        (Vector)
 import Data.Word          (Word32, Word8)
@@ -68,6 +68,9 @@ import qualified Data.ByteString.Lazy as BSLazy
 import qualified Data.Text            as Text
 import qualified Data.Vector          as Vector
 
+import qualified Text.Megaparsec      as P
+import qualified Text.Megaparsec.Char as P
+
 data AbiValue
   = AbiUInt         Int Word256
   | AbiInt          Int Int256
@@ -286,22 +289,43 @@ abiCalldata s xs = BSLazy.toStrict . runPut $ do
   putAbiSeq xs
 
 parseTypeName :: Text -> Maybe AbiType
-parseTypeName = \case
-  "address" ->
-    Just AbiAddressType
-  "bool" ->
-    Just AbiBoolType
-  "bytes" ->
-    Just AbiBytesDynamicType
-  "string" ->
-    Just AbiStringType
-  x | "uint" `isPrefixOf` x ->
-    Just . AbiUIntType . read . unpack $ Text.drop 4 x
-  x | "int" `isPrefixOf` x ->
-    Just . AbiIntType . read . unpack $ Text.drop 3 x
-  x | "bytes" `isPrefixOf` x ->
-    Just . AbiBytesType . read . unpack $ Text.drop 5 x
-  x -> error (show x)
+parseTypeName = P.parseMaybe typeWithArraySuffix
+
+typeWithArraySuffix :: P.Parsec () Text AbiType
+typeWithArraySuffix = do
+  base <- basicType
+  sizes <-
+    P.many $
+      P.between
+        (P.char '[') (P.char ']')
+        (P.many P.digitChar)
+
+  let
+    parseSize :: AbiType -> [Char] -> AbiType
+    parseSize t "" = AbiArrayDynamicType t
+    parseSize t s  = AbiArrayType (read s) t
+
+  pure (foldl parseSize base sizes)
+
+basicType :: P.Parsec () Text AbiType
+basicType =
+  P.choice
+    [ P.string "address" *> pure AbiAddressType
+    , P.string "bool"    *> pure AbiBoolType
+    , P.string "string"  *> pure AbiStringType
+
+    , sizedType "uint" AbiUIntType
+    , sizedType "int"  AbiIntType
+    , sizedType "bytes" AbiBytesType
+
+    , P.string "bytes" *> pure AbiBytesDynamicType
+    ]
+
+  where
+    sizedType :: Text -> (Int -> AbiType) -> P.Parsec () Text AbiType
+    sizedType s f = P.try $ do
+      void (P.string s)
+      fmap (f . read) (P.some P.digitChar)
 
 pack32 :: Int -> [Word32] -> Word256
 pack32 n xs =

src/EVM/Format.hs

@@ -83,16 +83,29 @@ showAbiValues :: Vector AbiValue -> Text
 showAbiValues vs =
   "(" <> intercalate ", " (toList (fmap showAbiValue vs)) <> ")"
 
+showAbiArray :: Vector AbiValue -> Text
+showAbiArray vs =
+  "[" <> intercalate ", " (toList (fmap showAbiValue vs)) <> "]"
+
 showAbiValue :: AbiValue -> Text
-showAbiValue (AbiUInt _ w)        = humanizeInteger w
-showAbiValue (AbiInt _ w)         = humanizeInteger w
-showAbiValue (AbiAddress w160)    = pack $ "0x" ++ (showHex w160 "")
-showAbiValue (AbiBool b)          = pack $ show b
-showAbiValue (AbiBytes _ bs)      = formatBytes bs
-showAbiValue (AbiBytesDynamic bs) = formatBinary bs
-showAbiValue (AbiString bs)       = formatQString bs
--- TODO: arrays
-showAbiValue value = pack $ show value
+showAbiValue (AbiUInt _ w) =
+  pack $ show w
+showAbiValue (AbiInt _ w) =
+  pack $ show w
+showAbiValue (AbiBool b) =
+  pack $ show b
+showAbiValue (AbiAddress w160) =
+  pack $ "0x" ++ (showHex w160 "")
+showAbiValue (AbiBytes _ bs) =
+  formatBytes bs
+showAbiValue (AbiBytesDynamic bs) =
+  formatBinary bs
+showAbiValue (AbiString bs) =
+  formatQString bs
+showAbiValue (AbiArray _ _ xs) =
+  showAbiArray xs
+showAbiValue (AbiArrayDynamic _ xs) =
+  showAbiArray xs
 
 isPrintable :: ByteString -> Bool
 isPrintable =