Merge pull request #10193 from ethereum/revert-test

Add tests for empty string literals in the ABI and fix TestFileParser

test/libsolidity/semanticTests/abiEncoderV1/abi_encode_empty_string.sol

@@ -0,0 +1,34 @@
+contract C {
+    function f1() public returns (bytes memory) {
+        return abi.encode("");
+    }
+    function f2(string calldata msg) public returns (bytes memory) {
+        return abi.encode(msg);
+    }
+    function g1() public returns (bytes memory) {
+        return abi.encodePacked("");
+    }
+    function g2(string calldata msg) public returns (bytes memory) {
+        return abi.encodePacked(msg);
+    }
+    function h1() public returns (bytes memory) {
+        return abi.encodeWithSelector(0x00000001, "");
+    }
+    function h2(string calldata msg) public returns (bytes memory) {
+        return abi.encodeWithSelector(0x00000001, msg);
+    }
+}
+
+// ====
+// ABIEncoderV1Only: true
+// compileViaYul: false
+// ----
+// f1() -> 0x20, 0x60, 0x20, 0, 0
+// f2(string): 0x20, 0 -> 0x20, 0x40, 0x20, 0
+// f2(string): 0x20, 0, 0 -> 0x20, 0x40, 0x20, 0
+// g1() -> 32, 0
+// g2(string): 0x20, 0 -> 0x20, 0
+// g2(string): 0x20, 0, 0 -> 0x20, 0
+// h1() -> 0x20, 0x64, 26959946667150639794667015087019630673637144422540572481103610249216, 862718293348820473429344482784628181556388621521298319395315527974912, 0, 0
+// h2(string): 0x20, 0 -> 0x20, 0x44, 26959946667150639794667015087019630673637144422540572481103610249216, 862718293348820473429344482784628181556388621521298319395315527974912, 0
+// h2(string): 0x20, 0, 0 -> 0x20, 0x44, 26959946667150639794667015087019630673637144422540572481103610249216, 862718293348820473429344482784628181556388621521298319395315527974912, 0

test/libsolidity/semanticTests/revertStrings/empty_v1.sol

@@ -0,0 +1,18 @@
+pragma abicoder v1;
+contract C {
+	function f() public {
+		revert("");
+	}
+	function g(string calldata msg) public {
+		revert(msg);
+	}
+}
+// ====
+// ABIEncoderV1Only: true
+// EVMVersion: >=byzantium
+// compileViaYul: false
+// revertStrings: debug
+// ----
+// f() -> FAILURE, hex"08c379a0", 0x20, 0, ""
+// g(string): 0x20, 0, "" -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): 0x20, 0 -> FAILURE, hex"08c379a0", 0x20, 0

test/libsolidity/semanticTests/revertStrings/empty_v1_yul.sol

@@ -0,0 +1,18 @@
+contract C {
+	function f() public {
+		revert("");
+	}
+	function g(string calldata msg) public {
+		revert(msg);
+	}
+}
+// ====
+// ABIEncoderV1Only: true
+// EVMVersion: >=byzantium
+// compileViaYul: true
+// revertStrings: debug
+// ----
+// f() -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): "" -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): 0x20, 0, "" -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): 0x20, 0 -> FAILURE, hex"08c379a0", 0x20, 0

test/libsolidity/semanticTests/revertStrings/empty_v2.sol

@@ -0,0 +1,18 @@
+pragma experimental ABIEncoderV2;
+contract C {
+	function f() public {
+		revert("");
+	}
+	function g(string calldata msg) public {
+		revert(msg);
+	}
+}
+// ====
+// EVMVersion: >=byzantium
+// compileViaYul: also
+// revertStrings: debug
+// ----
+// f() -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): "" -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): 0x20, 0, "" -> FAILURE, hex"08c379a0", 0x20, 0
+// g(string): 0x20, 0 -> FAILURE, hex"08c379a0", 0x20, 0

test/libsolidity/semanticTests/strings/empty_string.sol

@@ -0,0 +1,9 @@
+contract C {
+    function f() public pure returns (string memory) {
+        return "";
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 0x20, 0

test/libsolidity/semanticTests/strings/empty_string_input.sol

@@ -0,0 +1,30 @@
+contract C {
+    function f() public pure returns (string memory) {
+        return "";
+    }
+    function g(string calldata msg) public pure returns (string memory) {
+        return msg;
+    }
+    function h(string calldata msg, uint256 v) public pure returns (string memory, uint256) {
+        return (msg, v);
+    }
+    // Adjusting order of input/output intentionally.
+    function i(string calldata msg1, uint256 v, string calldata msg2) public pure returns (string memory, string memory, uint256) {
+        return (msg1, msg2, v);
+    }
+    function j(string calldata msg1, uint256 v) public pure returns (string memory, string memory, uint256) {
+        return (msg1, "", v);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 0x20, 0
+// g(string): 0x20, 0, "" -> 0x20, 0
+// g(string): 0x20, 0 -> 0x20, 0
+// h(string,uint256): 0x40, 0x888, 0, "" -> 0x40, 0x0888, 0
+// h(string,uint256): 0x40, 0x888, 0 -> 0x40, 0x0888, 0
+// i(string,uint256,string): 0x60, 0x888, 0x60, 0, "" -> 0x60, 0x80, 0x0888, 0, 0
+// i(string,uint256,string): 0x60, 0x888, 0x60, 0 -> 0x60, 0x80, 0x0888, 0, 0
+// j(string,uint256): 0x40, 0x888, 0, "" -> 0x60, 0x80, 0x0888, 0, 0
+// j(string,uint256): 0x40, 0x888, 0 -> 0x60, 0x80, 0x0888, 0, 0

test/libsolidity/util/TestFileParser.cpp

@@ -503,9 +503,9 @@ void TestFileParser::Scanner::scanNextToken()
 		return TokenDesc{Token::Identifier, _literal};
 	};
 
-	auto selectToken = [this](Token _token, std::string const& _literal = "") -> TokenDesc {
+	auto selectToken = [this](Token _token, std::optional<std::string> _literal = std::nullopt) -> TokenDesc {
 		advance();
-		return make_pair(_token, !_literal.empty() ? _literal : formatToken(_token));
+		return make_pair(_token, _literal.has_value() ? *_literal : formatToken(_token));
 	};
 
 	TokenDesc token = make_pair(Token::Unknown, "");

test/libsolidity/util/TestFileParser.h

@@ -120,8 +120,6 @@ private:
 		std::string m_line;
 		std::string::const_iterator m_char;
 
-		std::string m_currentLiteral;
-
 		TokenDesc m_currentToken;
 	};