Small fixes to typed AST (#50)

Add `Hash` derive for `SourceLocation`, fix schema for `TryCatchClause`
and add test for it.

I am currently working on
foundry-rs/foundry#4034 and it requires usage
of native solc AST, so I might be opening some other PRs around it as it
seems that we are not using current models anywhere and they might be a
bit outdated

src/artifacts/ast/lowfidelity.rs

@@ -62,7 +62,7 @@ impl Node {
 /// Represents the source location of a node: `<start byte>:<length>:<source index>`.
 ///
 /// The `length` and `index` can be -1 which is represented as `None`
-#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Hash)]
 pub struct SourceLocation {
     pub start: usize,
     pub length: Option<usize>,

src/artifacts/ast/misc.rs

@@ -4,7 +4,7 @@ use std::{fmt, fmt::Write, str::FromStr};
 /// Represents the source location of a node: `<start byte>:<length>:<source index>`.
 ///
 /// The `start`, `length` and `index` can be -1 which is represented as `None`
-#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Hash)]
 pub struct SourceLocation {
     pub start: Option<usize>,
     pub length: Option<usize>,

src/artifacts/ast/mod.rs

@@ -944,8 +944,7 @@ ast_node!(
     struct TryCatchClause {
         block: Block,
         error_name: String,
-        #[serde(default, deserialize_with = "serde_helpers::default_for_null")]
-        parameters: Vec<ParameterList>,
+        parameters: Option<ParameterList>,
     }
 );
 

test-data/ast/try_catch.json

@@ -0,0 +1 @@
+{"absolutePath":"src/X.sol","id":40896,"exportedSymbols":{"SomeContract":[40895]},"nodeType":"SourceUnit","src":"0:243:17","nodes":[{"id":40895,"nodeType":"ContractDefinition","src":"0:243:17","nodes":[{"id":40894,"nodeType":"FunctionDefinition","src":"28:213:17","nodes":[],"body":{"id":40893,"nodeType":"Block","src":"50:191:17","nodes":[],"statements":[{"clauses":[{"block":{"id":40880,"nodeType":"Block","src":"75:30:17","statements":[]},"errorName":"","id":40881,"nodeType":"TryCatchClause","src":"75:30:17"},{"block":{"id":40885,"nodeType":"Block","src":"140:30:17","statements":[]},"errorName":"Error","id":40886,"nodeType":"TryCatchClause","parameters":{"id":40884,"nodeType":"ParameterList","parameters":[{"constant":false,"id":40883,"mutability":"mutable","name":"reason","nameLocation":"132:6:17","nodeType":"VariableDeclaration","scope":40886,"src":"118:20:17","stateVariable":false,"storageLocation":"memory","typeDescriptions":{"typeIdentifier":"t_string_memory_ptr","typeString":"string"},"typeName":{"id":40882,"name":"string","nodeType":"ElementaryTypeName","src":"118:6:17","typeDescriptions":{"typeIdentifier":"t_string_storage_ptr","typeString":"string"}},"visibility":"internal"}],"src":"117:22:17"},"src":"106:64:17"},{"block":{"id":40890,"nodeType":"Block","src":"205:30:17","statements":[]},"errorName":"","id":40891,"nodeType":"TryCatchClause","parameters":{"id":40889,"nodeType":"ParameterList","parameters":[{"constant":false,"id":40888,"mutability":"mutable","name":"lowLevelData","nameLocation":"191:12:17","nodeType":"VariableDeclaration","scope":40891,"src":"178:25:17","stateVariable":false,"storageLocation":"memory","typeDescriptions":{"typeIdentifier":"t_bytes_memory_ptr","typeString":"bytes"},"typeName":{"id":40887,"name":"bytes","nodeType":"ElementaryTypeName","src":"178:5:17","typeDescriptions":{"typeIdentifier":"t_bytes_storage_ptr","typeString":"bytes"}},"visibility":"internal"}],"src":"177:27:17"},"src":"171:64:17"}],"externalCall":{"arguments":[],"expression":{"argumentTypes":[],"expression":{"id":40877,"name":"this","nodeType":"Identifier","overloadedDeclarations":[],"referencedDeclaration":-28,"src":"64:4:17","typeDescriptions":{"typeIdentifier":"t_contract$_SomeContract_$40895","typeString":"contract SomeContract"}},"id":40878,"isConstant":false,"isLValue":false,"isPure":false,"lValueRequested":false,"memberLocation":"69:3:17","memberName":"foo","nodeType":"MemberAccess","referencedDeclaration":40894,"src":"64:8:17","typeDescriptions":{"typeIdentifier":"t_function_external_nonpayable$__$returns$__$","typeString":"function () external"}},"id":40879,"isConstant":false,"isLValue":false,"isPure":false,"kind":"functionCall","lValueRequested":false,"nameLocations":[],"names":[],"nodeType":"FunctionCall","src":"64:10:17","tryCall":true,"typeDescriptions":{"typeIdentifier":"t_tuple$__$","typeString":"tuple()"}},"id":40892,"nodeType":"TryStatement","src":"60:175:17"}]},"functionSelector":"c2985578","implemented":true,"kind":"function","modifiers":[],"name":"foo","nameLocation":"37:3:17","parameters":{"id":40875,"nodeType":"ParameterList","parameters":[],"src":"40:2:17"},"returnParameters":{"id":40876,"nodeType":"ParameterList","parameters":[],"src":"50:0:17"},"scope":40895,"stateMutability":"nonpayable","virtual":false,"visibility":"public"}],"abstract":false,"baseContracts":[],"canonicalName":"SomeContract","contractDependencies":[],"contractKind":"contract","fullyImplemented":true,"linearizedBaseContracts":[40895],"name":"SomeContract","nameLocation":"9:12:17","scope":40896,"usedErrors":[],"usedEvents":[]}]}