Merge pull request #9306 from ethereum/yul-restrict-dot

[BREAKING] Restrict dots in Yul identifiers

Changelog.md

@@ -13,7 +13,7 @@ Breaking changes:
 
 Language Features:
  * Yul: Disallow EVM instruction `pc()`.
-
+ * Yul: Disallow consecutive and trailing dots in identifiers. Leading dots were already disallowed.
 
 Compiler Features:
 

libyul/AsmAnalysis.cpp

@@ -197,7 +197,10 @@ void AsmAnalyzer::operator()(VariableDeclaration const& _varDecl)
 				m_currentScope->insideFunction()
 			);
 	for (auto const& variable: _varDecl.variables)
+	{
+		expectValidIdentifier(variable.name, variable.location);
 		expectValidType(variable.type, variable.location);
+	}
 
 	if (_varDecl.value)
 	{
@@ -237,11 +240,13 @@ void AsmAnalyzer::operator()(VariableDeclaration const& _varDecl)
 void AsmAnalyzer::operator()(FunctionDefinition const& _funDef)
 {
 	yulAssert(!_funDef.name.empty(), "");
+	expectValidIdentifier(_funDef.name, _funDef.location);
 	Block const* virtualBlock = m_info.virtualBlocks.at(&_funDef).get();
 	yulAssert(virtualBlock, "");
 	Scope& varScope = scope(virtualBlock);
 	for (auto const& var: _funDef.parameters + _funDef.returnVariables)
 	{
+		expectValidIdentifier(var.name, var.location);
 		expectValidType(var.type, var.location);
 		m_activeVariables.insert(&std::get<Scope::Variable>(varScope.identifiers.at(var.name)));
 	}
@@ -517,6 +522,26 @@ Scope& AsmAnalyzer::scope(Block const* _block)
 	return *scopePtr;
 }
 
+void AsmAnalyzer::expectValidIdentifier(YulString _identifier, SourceLocation const& _location)
+{
+	// NOTE: the leading dot case is handled by the parser not allowing it.
+
+	if (boost::ends_with(_identifier.str(), "."))
+		m_errorReporter.syntaxError(
+			3384_error,
+			_location,
+			"\"" + _identifier.str() + "\" is not a valid identifier (ends with a dot)."
+		);
+
+	if (_identifier.str().find("..") != std::string::npos)
+		m_errorReporter.syntaxError(
+			7771_error,
+			_location,
+			"\"" + _identifier.str() + "\" is not a valid identifier (contains consecutive dots)."
+		);
+
+}
+
 void AsmAnalyzer::expectValidType(YulString _type, SourceLocation const& _location)
 {
 	if (!m_dialect.types.count(_type))

libyul/AsmAnalysis.h

@@ -108,6 +108,7 @@ private:
 	void checkAssignment(Identifier const& _variable, YulString _valueType);
 
 	Scope& scope(Block const* _block);
+	void expectValidIdentifier(YulString _identifier, langutil::SourceLocation const& _location);
 	void expectValidType(YulString _type, langutil::SourceLocation const& _location);
 	void expectType(YulString _expectedType, YulString _givenType, langutil::SourceLocation const& _location);
 

test/libyul/yulSyntaxTests/are_we_perl_yet.yul

@@ -4,3 +4,9 @@
     _...(a...)
 }
 // ----
+// SyntaxError 3384: (6-27): "_..." is not a valid identifier (ends with a dot).
+// SyntaxError 7771: (6-27): "_..." is not a valid identifier (contains consecutive dots).
+// SyntaxError 3384: (20-23): "$.." is not a valid identifier (ends with a dot).
+// SyntaxError 7771: (20-23): "$.." is not a valid identifier (contains consecutive dots).
+// SyntaxError 3384: (36-40): "a..." is not a valid identifier (ends with a dot).
+// SyntaxError 7771: (36-40): "a..." is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_consecutive_function.yul

@@ -2,3 +2,4 @@
     function x..y() {}
 }
 // ----
+// SyntaxError 7771: (6-24): "x..y" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_consecutive_function_arg.yul

@@ -2,3 +2,4 @@
     function x(a..b) {}
 }
 // ----
+// SyntaxError 7771: (17-21): "a..b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_consecutive_function_ret.yul

@@ -2,3 +2,4 @@
     function x() -> a..b {}
 }
 // ----
+// SyntaxError 7771: (22-26): "a..b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_consecutive_variabledeclaration.yul

@@ -2,3 +2,4 @@
     let a..b := 1
 }
 // ----
+// SyntaxError 7771: (10-14): "a..b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_ellipse_function.yul

@@ -2,3 +2,4 @@
     function x...y() {}
 }
 // ----
+// SyntaxError 7771: (6-25): "x...y" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_ellipse_function_arg.yul

@@ -2,3 +2,4 @@
     function x(a...b) {}
 }
 // ----
+// SyntaxError 7771: (17-22): "a...b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_ellipse_function_ret.yul

@@ -2,3 +2,4 @@
     function x() -> a...b {}
 }
 // ----
+// SyntaxError 7771: (22-27): "a...b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_ellipse_variabledeclaration.yul

@@ -2,3 +2,4 @@
     let a...b := 1
 }
 // ----
+// SyntaxError 7771: (10-15): "a...b" is not a valid identifier (contains consecutive dots).

test/libyul/yulSyntaxTests/dot_trailing_function.yul

@@ -2,3 +2,4 @@
     function x.() {}
 }
 // ----
+// SyntaxError 3384: (6-22): "x." is not a valid identifier (ends with a dot).

test/libyul/yulSyntaxTests/dot_trailing_function_arg.yul

@@ -2,3 +2,4 @@
     function x(a.) {}
 }
 // ----
+// SyntaxError 3384: (17-19): "a." is not a valid identifier (ends with a dot).

test/libyul/yulSyntaxTests/dot_trailing_function_ret.yul

@@ -2,3 +2,4 @@
     function x() -> a. {}
 }
 // ----
+// SyntaxError 3384: (22-24): "a." is not a valid identifier (ends with a dot).

test/libyul/yulSyntaxTests/dot_trailing_variabledeclaration.yul

@@ -2,3 +2,4 @@
     let a. := 1
 }
 // ----
+// SyntaxError 3384: (10-12): "a." is not a valid identifier (ends with a dot).