From 1488a1ceb807633beef3349ad785ee98be45742d Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Tue, 25 Feb 2020 18:42:16 +0100
Subject: [PATCH] Refactor isConstant to add "immutable".

---
 libsolidity/ast/AST.cpp             |  2 +-
 libsolidity/ast/AST.h               | 10 ++++++----
 libsolidity/ast/ASTJsonImporter.cpp |  8 +++++++-
 libsolidity/parsing/Parser.cpp      |  6 +++---
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/libsolidity/ast/AST.cpp b/libsolidity/ast/AST.cpp
index 90084f9c4..6b03c7b58 100644
--- a/libsolidity/ast/AST.cpp
+++ b/libsolidity/ast/AST.cpp
@@ -390,7 +390,7 @@ DeclarationAnnotation& Declaration::annotation() const
 bool VariableDeclaration::isLValue() const
 {
 	// Constant declared variables are Read-Only
-	if (m_isConstant)
+	if (isConstant())
 		return false;
 	// External function arguments of reference type are Read-Only
 	if (isExternalCallableParameter() && dynamic_cast<ReferenceType const*>(type()))
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 336c221c6..adb957cfe 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -814,6 +814,7 @@ class VariableDeclaration: public Declaration
 {
 public:
 	enum Location { Unspecified, Storage, Memory, CallData };
+	enum class Constantness { Mutable, Immutable, Constant };
 
 	VariableDeclaration(
 		int64_t _id,
@@ -824,7 +825,7 @@ public:
 		Visibility _visibility,
 		bool _isStateVar = false,
 		bool _isIndexed = false,
-		bool _isConstant = false,
+		Constantness _constantness = Constantness::Mutable,
 		ASTPointer<OverrideSpecifier> const& _overrides = nullptr,
 		Location _referenceLocation = Location::Unspecified
 	):
@@ -833,7 +834,7 @@ public:
 		m_value(_value),
 		m_isStateVariable(_isStateVar),
 		m_isIndexed(_isIndexed),
-		m_isConstant(_isConstant),
+		m_constantness(_constantness),
 		m_overrides(_overrides),
 		m_location(_referenceLocation) {}
 
@@ -877,7 +878,7 @@ public:
 	bool hasReferenceOrMappingType() const;
 	bool isStateVariable() const { return m_isStateVariable; }
 	bool isIndexed() const { return m_isIndexed; }
-	bool isConstant() const { return m_isConstant; }
+	bool isConstant() const { return m_constantness == Constantness::Constant; }
 	ASTPointer<OverrideSpecifier> const& overrides() const { return m_overrides; }
 	Location referenceLocation() const { return m_location; }
 	/// @returns a set of allowed storage locations for the variable.
@@ -904,7 +905,8 @@ private:
 	ASTPointer<Expression> m_value;
 	bool m_isStateVariable = false; ///< Whether or not this is a contract state variable
 	bool m_isIndexed = false; ///< Whether this is an indexed variable (used by events).
-	bool m_isConstant = false; ///< Whether the variable is a compile-time constant.
+	/// Whether the variable is "constant", "immutable" or non-marked (mutable).
+	Constantness m_constantness = Constantness::Mutable;
 	ASTPointer<OverrideSpecifier> m_overrides; ///< Contains the override specifier node
 	Location m_location = Location::Unspecified; ///< Location of the variable if it is of reference type.
 };
diff --git a/libsolidity/ast/ASTJsonImporter.cpp b/libsolidity/ast/ASTJsonImporter.cpp
index aa28e3f17..26a7c7b7e 100644
--- a/libsolidity/ast/ASTJsonImporter.cpp
+++ b/libsolidity/ast/ASTJsonImporter.cpp
@@ -411,6 +411,12 @@ ASTPointer<VariableDeclaration> ASTJsonImporter::createVariableDeclaration(Json:
 {
 	astAssert(_node["name"].isString(), "Expected 'name' to be a string!");
 
+	VariableDeclaration::Constantness constantness{};
+	if (memberAsBool(_node, "constant"))
+		constantness = VariableDeclaration::Constantness::Constant;
+	else
+		constantness = VariableDeclaration::Constantness::Mutable;
+
 	return createASTNode<VariableDeclaration>(
 		_node,
 		nullOrCast<TypeName>(member(_node, "typeName")),
@@ -419,7 +425,7 @@ ASTPointer<VariableDeclaration> ASTJsonImporter::createVariableDeclaration(Json:
 		visibility(_node),
 		memberAsBool(_node, "stateVariable"),
 		_node.isMember("indexed") ? memberAsBool(_node, "indexed") : false,
-		memberAsBool(_node, "constant"),
+		constantness,
 		_node["overrides"].isNull() ? nullptr : createOverrideSpecifier(member(_node, "overrides")),
 		location(_node)
 	);
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index 99aa6e2a1..edf43377f 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -695,7 +695,7 @@ ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(
 		);
 
 	bool isIndexed = false;
-	bool isDeclaredConst = false;
+	VariableDeclaration::Constantness constantness = VariableDeclaration::Constantness::Mutable;
 	ASTPointer<OverrideSpecifier> overrides = nullptr;
 	Visibility visibility(Visibility::Default);
 	VariableDeclaration::Location location = VariableDeclaration::Location::Unspecified;
@@ -731,7 +731,7 @@ ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(
 			if (_options.allowIndexed && token == Token::Indexed)
 				isIndexed = true;
 			else if (token == Token::Constant)
-				isDeclaredConst = true;
+				constantness = VariableDeclaration::Constantness::Constant;
 			else if (_options.allowLocationSpecifier && TokenTraits::isLocationSpecifier(token))
 			{
 				if (location != VariableDeclaration::Location::Unspecified)
@@ -790,7 +790,7 @@ ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(
 		visibility,
 		_options.isStateVariable,
 		isIndexed,
-		isDeclaredConst,
+		constantness,
 		overrides,
 		location
 	);