Allow event definitions at file level

Changelog.md

@@ -1,6 +1,7 @@
 ### 0.8.22 (unreleased)
 
 Language Features:
+ * Allow defining events at file level.
 
 
 Compiler Features:

docs/contracts/events.rst

@@ -9,9 +9,10 @@ Events
 Solidity events give an abstraction on top of the EVM's logging functionality.
 Applications can subscribe and listen to these events through the RPC interface of an Ethereum client.
 
-Events are inheritable members of contracts. When you call them, they cause the
+Events can be defined at file level or as inheritable members of contracts (including interfaces and libraries).
+When you call them, they cause the
 arguments to be stored in the transaction's log - a special data structure
-in the blockchain. These logs are associated with the address of the contract,
+in the blockchain. These logs are associated with the address of the contract that emitted them,
 are incorporated into the blockchain, and stay there as long as a block is
 accessible (forever as of now, but this might
 change with Serenity). The Log and its event data is not accessible from within

docs/grammar/SolidityParser.g4

@@ -22,6 +22,7 @@ sourceUnit: (
 	| enumDefinition
 	| userDefinedValueTypeDefinition
 	| errorDefinition
+	| eventDefinition
 )* EOF;
 
 //@doc: inline

docs/structure-of-a-contract.rst

@@ -112,11 +112,11 @@ Events are convenience interfaces with the EVM logging facilities.
 .. code-block:: solidity
 
     // SPDX-License-Identifier: GPL-3.0
-    pragma solidity >=0.4.21 <0.9.0;
+    pragma solidity ^0.8.22;
 
-    contract SimpleAuction {
     event HighestBidIncreased(address bidder, uint amount); // Event
 
+    contract SimpleAuction {
         function bid() public payable {
             // ...
             emit HighestBidIncreased(msg.sender, msg.value); // Triggering event

libsolidity/parsing/Parser.cpp

@@ -131,6 +131,9 @@ ASTPointer<SourceUnit> Parser::parse(CharStream& _charStream)
 			case Token::Function:
 				nodes.push_back(parseFunctionDefinition(true));
 				break;
+			case Token::Event:
+				nodes.push_back(parseEventDefinition());
+				break;
 			default:
 				if (
 					// Workaround because `error` is not a keyword.

test/libsolidity/ABIJson/event_file_level.sol

@@ -0,0 +1,107 @@
+event Event();
+event Event(uint);
+
+event UnusedEvent();
+
+function f() {
+    emit Event();
+}
+
+contract C {
+    function c_main() public {
+        emit Event(42);
+        f();
+    }
+}
+
+contract D is C {
+    event Event(string);
+
+    function d_main() public {
+        emit Event("abc");
+    }
+}
+// ----
+//     :C
+// [
+//   {
+//     "anonymous": false,
+//     "inputs": [],
+//     "name": "Event",
+//     "type": "event"
+//   },
+//   {
+//     "anonymous": false,
+//     "inputs":
+//     [
+//       {
+//         "indexed": false,
+//         "internalType": "uint256",
+//         "name": "",
+//         "type": "uint256"
+//       }
+//     ],
+//     "name": "Event",
+//     "type": "event"
+//   },
+//   {
+//     "inputs": [],
+//     "name": "c_main",
+//     "outputs": [],
+//     "stateMutability": "nonpayable",
+//     "type": "function"
+//   }
+// ]
+//
+//
+//     :D
+// [
+//   {
+//     "anonymous": false,
+//     "inputs": [],
+//     "name": "Event",
+//     "type": "event"
+//   },
+//   {
+//     "anonymous": false,
+//     "inputs":
+//     [
+//       {
+//         "indexed": false,
+//         "internalType": "uint256",
+//         "name": "",
+//         "type": "uint256"
+//       }
+//     ],
+//     "name": "Event",
+//     "type": "event"
+//   },
+//   {
+//     "anonymous": false,
+//     "inputs":
+//     [
+//       {
+//         "indexed": false,
+//         "internalType": "string",
+//         "name": "",
+//         "type": "string"
+//       }
+//     ],
+//     "name": "Event",
+//     "type": "event"
+//   },
+//   {
+//     "inputs": [],
+//     "name": "c_main",
+//     "outputs": [],
+//     "stateMutability": "nonpayable",
+//     "type": "function"
+//   },
+//   {
+//     "inputs": [],
+//     "name": "d_main",
+//     "outputs": [],
+//     "stateMutability": "nonpayable",
+//     "type": "function"
+//   }
+// ]

test/libsolidity/SemanticTest.cpp

@@ -274,7 +274,7 @@ std::optional<AnnotatedEventSignature> SemanticTest::matchEvent(util::h256 const
 	for (std::string& contractName: m_compiler.contractNames())
 	{
 		ContractDefinition const& contract = m_compiler.contractDefinition(contractName);
-		for (EventDefinition const* event: contract.events())
+		for (EventDefinition const* event: contract.events() + contract.usedInterfaceEvents())
 		{
 			FunctionTypePointer eventFunctionType = event->functionType(true);
 			if (!event->isAnonymous() && keccak256(eventFunctionType->externalSignature()) == hash)

test/libsolidity/natspecJSON/emit_file_level_event.sol

@@ -0,0 +1,39 @@
+/// @notice Userdoc for file-level event E.
+/// @dev Devdoc for file-level E.
+event E();
+
+contract C {
+    function f() public {
+        emit E();
+    }
+}
+
+// ----
+// ----
+// :C devdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "details": "Devdoc for file-level E."
+//         }
+//     },
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :C userdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "notice": "Userdoc for file-level event E."
+//         }
+//     },
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }

test/libsolidity/natspecJSON/emit_file_level_event_inheritance.sol

@@ -0,0 +1,69 @@
+/// @notice Userdoc for file-level event E.
+/// @dev Devdoc for file-level E.
+event E();
+
+contract C {
+    function f() public {
+        emit E();
+    }
+}
+
+contract D is C {}
+
+// ----
+// ----
+// :C devdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "details": "Devdoc for file-level E."
+//         }
+//     },
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :C userdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "notice": "Userdoc for file-level event E."
+//         }
+//     },
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :D devdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "details": "Devdoc for file-level E."
+//         }
+//     },
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :D userdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "notice": "Userdoc for file-level event E."
+//         }
+//     },
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }

test/libsolidity/natspecJSON/emit_file_level_event_with_same_signature_as_foreign_event.sol

@@ -0,0 +1,60 @@
+/// @notice Userdoc for file-level event E.
+/// @dev Devdoc for file-level E.
+event E();
+
+contract F {
+    /// @notice Userdoc for event F.E.
+    /// @dev Devdoc for event F.E.
+    event E();
+}
+
+contract C {
+    function f() public {
+        emit E();
+        emit F.E();
+    }
+}
+
+// ----
+// ----
+// :C devdoc
+// {
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :C userdoc
+// {
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :F devdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "details": "Devdoc for event F.E."
+//         }
+//     },
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :F userdoc
+// {
+//     "events":
+//     {
+//         "E()":
+//         {
+//             "notice": "Userdoc for event F.E."
+//         }
+//     },
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }

test/libsolidity/natspecJSON/unused_file_level_event.sol

@@ -0,0 +1,21 @@
+/// @notice Userdoc for file-level event E.
+/// @dev Devdoc for file-level E.
+event E();
+
+contract C {}
+
+// ----
+// ----
+// :C devdoc
+// {
+//     "kind": "dev",
+//     "methods": {},
+//     "version": 1
+// }
+//
+// :C userdoc
+// {
+//     "kind": "user",
+//     "methods": {},
+//     "version": 1
+// }

test/libsolidity/semanticTests/events/event_emit_file_level.sol

@@ -0,0 +1,10 @@
+event Deposit(address indexed _from, bytes32 indexed _id, uint _value);
+
+contract ClientReceipt {
+    function deposit(bytes32 _id) public payable {
+        emit Deposit(msg.sender, _id, msg.value);
+    }
+}
+// ----
+// deposit(bytes32), 18 wei: 0x1234 ->
+// ~ emit Deposit(address,bytes32,uint256): #0x1212121212121212121212121212120000000012, #0x1234, 0x12

test/libsolidity/semanticTests/events/event_selector_file_level.sol

@@ -0,0 +1,15 @@
+event E();
+
+library L {
+    event E();
+}
+
+contract C {
+    function main() external pure returns (bytes32, bytes32) {
+        assert(E.selector == L.E.selector);
+
+        return (E.selector, L.E.selector);
+    }
+}
+// ----
+// main() -> 0x92bbf6e823a631f3c8e09b1c8df90f378fb56f7fbc9701827e1ff8aad7f6a028, 0x92bbf6e823a631f3c8e09b1c8df90f378fb56f7fbc9701827e1ff8aad7f6a028

test/libsolidity/semanticTests/events/event_shadowing_file_level.sol

@@ -0,0 +1,38 @@
+event E();
+
+library L1 {
+    event E(string);
+}
+
+library L2 {
+    event E();
+}
+
+library K {
+    function main() internal pure returns (bytes32, bytes32, bytes32) {
+        // Here E is the global event.
+        assert(E.selector != L1.E.selector);
+        assert(E.selector == L2.E.selector);
+
+        return (E.selector, L1.E.selector, L2.E.selector);
+    }
+}
+
+contract C {
+    event E(string);
+
+    function main() external pure returns (bytes32, bytes32, bytes32) {
+        // Here E is the local event.
+        assert(E.selector == L1.E.selector);
+        assert(E.selector != L2.E.selector);
+
+        return (E.selector, L1.E.selector, L2.E.selector);
+    }
+
+    function k_main() external pure returns (bytes32, bytes32, bytes32) {
+        return K.main();
+    }
+}
+// ----
+// main() -> 0x3e9992c940c54ea252d3a34557cc3d3014281525c43d694f89d5f3dfd820b07d, 0x3e9992c940c54ea252d3a34557cc3d3014281525c43d694f89d5f3dfd820b07d, 0x92bbf6e823a631f3c8e09b1c8df90f378fb56f7fbc9701827e1ff8aad7f6a028
+// k_main() -> 0x92bbf6e823a631f3c8e09b1c8df90f378fb56f7fbc9701827e1ff8aad7f6a028, 0x3e9992c940c54ea252d3a34557cc3d3014281525c43d694f89d5f3dfd820b07d, 0x92bbf6e823a631f3c8e09b1c8df90f378fb56f7fbc9701827e1ff8aad7f6a028

test/libsolidity/semanticTests/events/events_with_same_name_file_level.sol

@@ -0,0 +1,32 @@
+event Deposit();
+event Deposit(address _addr);
+event Deposit(address _addr, uint _amount);
+event Deposit(address _addr, bool _flag);
+
+contract ClientReceipt {
+    function deposit() public returns (uint) {
+        emit Deposit();
+        return 1;
+    }
+    function deposit(address _addr) public returns (uint) {
+        emit Deposit(_addr);
+        return 2;
+    }
+    function deposit(address _addr, uint _amount) public returns (uint) {
+        emit Deposit(_addr, _amount);
+        return 3;
+    }
+    function deposit(address _addr, bool _flag) public returns (uint) {
+        emit Deposit(_addr, _flag);
+        return 4;
+    }
+}
+// ----
+// deposit() -> 1
+// ~ emit Deposit()
+// deposit(address): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988 -> 2
+// ~ emit Deposit(address): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988
+// deposit(address,uint256): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988, 100 -> 3
+// ~ emit Deposit(address,uint256): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988, 0x64
+// deposit(address,bool): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988, false -> 4
+// ~ emit Deposit(address,bool): 0x5082a85c489be6aa0f2e6693bf09cc1bbd35e988, false

test/libsolidity/syntaxTests/events/event_emit_qualified_file_level.sol

@@ -0,0 +1,8 @@
+==== Source: M.sol ====
+event E();
+==== Source: A.sol ====
+import "M.sol" as M;
+
+function f() {
+    emit M.E();
+}

test/libsolidity/syntaxTests/events/event_emit_simple_file_level.sol

@@ -0,0 +1,7 @@
+event E();
+
+contract C {
+    function f() public {
+        emit E();
+    }
+}

test/libsolidity/syntaxTests/events/event_selector_access_file_level.sol

@@ -0,0 +1,7 @@
+event E();
+
+contract C {
+    function f() external pure returns (bytes32) {
+        return E.selector;
+    }
+}

test/libsolidity/syntaxTests/events/file_level_event.sol

@@ -0,0 +1,11 @@
+event E1();
+event E2(uint);
+event E3(uint, string indexed, bytes, bool);
+event E4(int, int, int) anonymous;
+
+function f() {
+    emit E1();
+    emit E2(1);
+    emit E3(1, "abc", "abc", true);
+    emit E4(1, 2, 3);
+}

test/libsolidity/syntaxTests/events/file_level_event_duplicate_definition.sol

@@ -0,0 +1,4 @@
+event E();
+event E();
+// ----
+// DeclarationError 5883: (0-10): Event with same name and parameter types defined twice.

test/libsolidity/syntaxTests/events/file_level_event_duplicate_definition_via_import.sol

@@ -0,0 +1,8 @@
+==== Source: A.sol ====
+event E();
+==== Source: B.sol ====
+import "A.sol";
+
+event E();
+// ----
+// DeclarationError 5883: (B.sol:17-27): Event with same name and parameter types defined twice.

test/libsolidity/syntaxTests/events/file_level_event_import.sol

@@ -0,0 +1,12 @@
+==== Source: A.sol ====
+event EA();
+==== Source: B.sol ====
+event EB();
+==== Source: C.sol ====
+import "A.sol";
+import {EB} from "B.sol";
+
+function f() {
+    emit EA();
+    emit EB();
+}

test/libsolidity/syntaxTests/events/file_level_event_overloading.sol

@@ -0,0 +1,11 @@
+event E();
+event E(uint);
+event E(uint, string indexed, bytes, bool);
+event E(int, int, int) anonymous;
+
+function f() {
+    emit E();
+    emit E(1);
+    emit E(1, "abc", "abc", true);
+    emit E(1, 2, 3);
+}

test/libsolidity/syntaxTests/events/file_level_event_overloading_vs_shadowing.sol

@@ -0,0 +1,13 @@
+event E();
+
+contract C {
+    event E(uint);
+
+    function f() public {
+        emit E();
+        emit E(1);
+    }
+}
+// ----
+// Warning 2519: (29-43): This declaration shadows an existing declaration.
+// TypeError 6160: (84-87): Wrong argument count for function call: 0 arguments given but expected 1.

test/libsolidity/syntaxTests/events/file_level_event_shadowed_inside_contract.sol

@@ -0,0 +1,17 @@
+event E();
+
+contract C {
+    event E();
+}
+
+library L {
+    event E();
+}
+
+interface I {
+    event E();
+}
+// ----
+// Warning 2519: (29-39): This declaration shadows an existing declaration.
+// Warning 2519: (59-69): This declaration shadows an existing declaration.
+// Warning 2519: (91-101): This declaration shadows an existing declaration.

test/libsolidity/syntaxTests/events/file_level_event_shadowed_inside_contract_adds_anonymous.sol

@@ -0,0 +1,17 @@
+event E();
+
+contract C {
+    event E() anonymous;
+}
+
+library L {
+    event E() anonymous;
+}
+
+interface I {
+    event E() anonymous;
+}
+// ----
+// Warning 2519: (29-49): This declaration shadows an existing declaration.
+// Warning 2519: (69-89): This declaration shadows an existing declaration.
+// Warning 2519: (111-131): This declaration shadows an existing declaration.

test/libsolidity/syntaxTests/events/file_level_event_shadowing_contract.sol

@@ -0,0 +1,4 @@
+event E();
+contract E {}
+// ----
+// DeclarationError 2333: (11-24): Identifier already declared.

test/libsolidity/syntaxTests/events/file_level_event_shadowing_error.sol

@@ -0,0 +1,4 @@
+event E();
+error E();
+// ----
+// DeclarationError 2333: (11-21): Identifier already declared.

test/libsolidity/syntaxTests/events/file_level_event_using.sol

@@ -0,0 +1,6 @@
+event E();
+
+type T is uint;
+using {E} for T;
+// ----
+// TypeError 8187: (35-36): Expected function name.

test/libsolidity/syntaxTests/events/illegal_names_exception_file_level.sol

@@ -0,0 +1,4 @@
+// Exception for the illegal name list. External interface events
+event this();
+event super();
+event _();