done

Author: zeme-wana

plutus-core/plutus-core/src/PlutusCore/Parser/Type.hs

@@ -154,7 +154,10 @@ defaultUni = do
     , try $ someType @_ @BLS12_381.G2.Element <$ symbol "bls12_381_G2_element"
     , try $ someType @_ @BLS12_381.Pairing.MlResult <$ symbol "bls12_381_mlresult"
     , try $ someType @_ @Value <$ symbol "value"
-    , fail "Unknown type, expected one of: bool, integer, bytestring, string, unit, list, array, pair, data, value, bls12_381_G1_element, bls12_381_G2_element, bls12_381_mlresult, or a type application in parens"
+    , -- We include an explicit failure case here to produce clearer error messages.
+      -- Without this, using `choice` with `symbol` results in error messages that cover the longest possible SrcSpan,
+      -- which in this context would be 20 characters spanning the entire "bls12_381_G2_element" token.
+      fail "Unknown type, expected one of: bool, integer, bytestring, string, unit, list, array, pair, data, value, bls12_381_G1_element, bls12_381_G2_element, bls12_381_mlresult, or a type application in parens"
     ]
 
 tyName :: Parser TyName