From 2130c446e2c21f1f41a4e83ac8ad7da486318702 Mon Sep 17 00:00:00 2001
From: Christian Parpart <christian@parpart.family>
Date: Mon, 18 May 2020 16:55:09 +0200
Subject: [PATCH] Adds SourceUnit::replaceNode(_old, _new)

---
 libsolidity/ast/AST.cpp | 18 ++++++++++++++++++
 libsolidity/ast/AST.h   |  3 +++
 2 files changed, 21 insertions(+)

diff --git a/libsolidity/ast/AST.cpp b/libsolidity/ast/AST.cpp
index 3edb08476..9bc5c030d 100644
--- a/libsolidity/ast/AST.cpp
+++ b/libsolidity/ast/AST.cpp
@@ -27,6 +27,8 @@
 #include <libsolidity/ast/TypeProvider.h>
 #include <libsolutil/Keccak256.h>
 
+#include <boost/range/algorithm/find_if.hpp>
+#include <boost/range/algorithm/replace_if.hpp>
 #include <boost/algorithm/string.hpp>
 
 #include <algorithm>
@@ -72,6 +74,22 @@ set<SourceUnit const*> SourceUnit::referencedSourceUnits(bool _recurse, set<Sour
 	return sourceUnits;
 }
 
+void SourceUnit::replaceNode(ASTPointer<ASTNode> _oldNode, ASTPointer<ASTNode> _newNode)
+{
+	solAssert(
+		boost::range::find_if(
+			m_nodes,
+			[&](auto const& node) { return node->id() == _oldNode->id(); }
+		) != m_nodes.end(),
+		""
+	);
+	boost::range::replace_if(
+		m_nodes,
+		[&](auto const& node) { return node->id() == _oldNode->id(); },
+		_newNode
+	);
+}
+
 ImportAnnotation& ImportDirective::annotation() const
 {
 	return initAnnotation<ImportAnnotation>();
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 92b3324ab..cecf6afb9 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -173,6 +173,9 @@ public:
 	std::optional<std::string> const& licenseString() const { return m_licenseString; }
 	std::vector<ASTPointer<ASTNode>> nodes() const { return m_nodes; }
 
+	/// Replaces given top-level AST node with a new AST node.
+	void replaceNode(ASTPointer<ASTNode> _oldNode, ASTPointer<ASTNode> _newNode);
+
 	/// @returns a set of referenced SourceUnits. Recursively if @a _recurse is true.
 	std::set<SourceUnit const*> referencedSourceUnits(bool _recurse = false, std::set<SourceUnit const*> _skipList = std::set<SourceUnit const*>()) const;